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The R.A.P. Project (Reviews of Astro-Ph)

Zvezdy
(Arhiv Zvezdy:
v.2, 2003, v.1, 2002-2003)

Vypusk 202. 17-31 dekabrya 2008

arxiv:0812.4078 Proekt MiMeS: magnetizm massivnyh zvezd (The MiMeS Project: Magnetism in Massive Stars)
Authors: G.A. Wade et al.
Comments: 6 pages, 3 figures, proceedings of IAUS 259: Cosmic Magnetic Fields

MiMeS - Magnetism in Massive Stars. Proekt poluchil 640 chasov nablyudatel'nogo vremeni na franko-kanadsko-gavaiskom teleskope na protyazhenii 2008-2012 godov. Zadacha - ponyat' proishozhdenie magnitnyh polei massivnyh zvezd, ih svyazi so zvezdnym vetrom, a takzhe opredelit' ih vliyaniyu na evolyuciyu zvezd i ih konechnye produkty (kompaktnye ob'ekty). Detal'no budet izucheno okolo 20 zvezd. Dlya nih budut postroeny karty magnitnyh polei. Krome togo, budet i obzornaya programma, vklyuchayushaya v sebya uzhe bol'shoe chislo ob'ektov (okolo 150).

Sm. takzhe arxiv:0812.4079, gde privodyatsya pervye rezul'taty proekta.


Vypusk 201. 01-16 dekabrya 2008

obzor arxiv:0812.0046 Obzor kompleksa v Orione (Overview of the Orion complex)
Authors: John Bally
Comments: 26 pages, to be published in the Handbook of star formation regions, Vol. 1 Astronomical society of the Pacific, 2008, Ed. Bo Reiputh

Vyhodit zamechatel'nyi sbornik statei, v kotorom opisyvayutsya razlichnye oblasti zvezdoobrazovaniya. Prakticheski vse stat'i iz sbornika dostupny v Arhive. Ocherednaya poyavivshayasya stat'ya posvyashena blizhaishei oblasti zvezdoobrazovaniya v Orione, v kotoroi i seichas obrazuyutsya massivnye i malomassivnye zvezdy. Krome opisaniya sobstvenno kompleksa zvezdoobrazovaniya v Orione avtor dostatochno detal'no opisyvaet odin iz scenariev formirovaniya poyasa Gulda, i voobshe kartinu nedavnego zvezdoobrazovaniya v solnechnoi okrestnosti. Ochen' interesno i poznavatel'no.


obzor arxiv:0812.0482 Spektry belyh karlikov i modeli atmosfer (White dwarf spectra and atmosphere models)
Authors: Detlev Koester
Comments: 11 pages, to appear in Mem. S.A.I.

Avtor dostatochno podrobno rasskazyvaet o svoem kode dlya rascheta spektrov belyh karlikov, soprovozhdaya vse ssylkami na eshe bolee detal'noe izlozhenie. Kodu mnogo let, na protyazhenii kotoryh on nepreryvno modificirovalsya. Dumayu, chto seichas est' eshe bolee kachestvennye modeli (naprimer, u Suleimanova), no etot tekst polezen imenno kak sposob razobrat'sya v tom, chto i kak schitayut, a dal'neishie detali mozhno naiti po ssylkam.

Sm. takzhe rabotu arxiv:0812.0491, v kotoroi obsuzhdayutsya effekty, vliyayushie na opredelenie mass belyh karlikov pri nizkoi temperature.


item arxiv:0812.1227 Nablyudaemye proyavleniya elementov r-processa v naibolee staryh zvezdah Galaktiki (Observing the Signatures of the r-Process in the Oldest Galactic Stars).
Authors: Anna Frebel
Comments: 10 pages, to appear in the Proceedings of the "10th Symposium on Nuclei in the Cosmos (NIC X)"

Naibolee malometallichnye zvezdy Galaktiki odnovremenno yavlyayutsya samymi starymi v nei, poskol'ku byli sformirovany na samyh rannih etapah evolyucii Galaktiki iz gaza, eshe ne obogashennogo metallami. Na primere ekstremal'no malometallichnoi zvezdy HE 1523-0901, vozrast kotoroi ocenivaetsya v 13 mlrd let, avtorom raboty dan analiz nablyudaemyh soderzhanii tyazhelyh elementov Eu, Os, and Ir i radioaktivnyh Th i U.


item arxiv:0812.2354 Chego ozhidat' ot Gaia i kak eto povliyaet na vozrasta zvezd(The promise of Gaia and how it will influence stellar ages).
Authors: Carla Cacciari
Comments: 10 pages, 2 figures, IAU Symp. 258 on "The Ages of Stars"

Evropeiskii kosmicheskii proekt Gaia, zaplanirovannyi k zapusku v 2011 godu, pozvolit poluchit' astrometricheskie, fotometricheskie i spektroskopicheskie dannye dlya bolee chem milliarda zvezd yarche 20-i zvezdnoi velichiny. V stat'e dano opisanie instrumenta, privodyatsya ego osnovnye harakteristiki i obsuzhdayutsya nauchnye napravleniya, v kotoryh Gaia pozvolit dostich' revolyucionnyh izmenenii.


arxiv:0812.2561 Kratnos' zvezd s ekzoplanetami - novye malomassivnye zvezdnye komponenty u HD125612 i HD212301 (The multiplicity of exoplanet host stars - new low-mass stellar companions of the exoplanet host stars HD125612 and HD212301)
Authors: M. Mugrauer, R. Neuhauser
Comments: 7 pages, A&A in press

Obnaruzheny dva malomassivnyh (0.18 i 0.35 mass Solnca) sputnika u dvuh zvezd s ekzoplanetami. Odin iz nih (bolee massivnyi) nahoditsya vsego lish' v 230 a.e. ot vtoroi zvezdy. V principe, osoboi novizny tut net. Eto uzhe 42-ya i 43-ya dvoinaya sistema s ekzoplanetami. No polezno znat', chto dazhe bez ucheta effektov selekcii okolo 17% ekzoplanetnyh sistem nahodyatsya v dvoinyh i kratnyh sistemah.


Vypusk 199. 01-13 noyabrya 2008

obzor arxiv:0811.0487 Poterya massy massivnymi goryachimi zvezdami (Mass loss from hot massive stars)
Authors: J. Puls, J. S. Vink, F. Najarro
Comments: 116 pages, A&A Reviews

Ogromnyi obzor po potere veshestva massivnymi zvezdami. Po suti, tam obo vsem, chto kasaetsya dannoi temy. Budet kakoe-to vremya nastol'nym dlya vseh, kto s etim svyazan.


miniobzor arxiv:0811.1080 Seismologicheskaya programma CoRoT (The seismology programme of CoRoT)
Authors: E. Michel et al.
Comments: 12 pages, 16 figures, ESA Spec. Publ. 1306, p. 39-50

Sputnik CoRoT uzhe pochti dva goda nahoditsya na orbite (s 26 dekabrya 2006 g.). Osnovnaya zadacha sputnika - izuchenie pul'sacii zvezd - astroseismologiya. Takie issledovaniya pozvolyayut luchshe ponyat', kak eti svetila ustroeny vnutri, a znachit, proverit' nashi teorii vnutrennego stroeniya zvezd. Poputno, konechno, mozhno poluchat' vsyakie drugie rezul'taty, naprimer, svyazannye s ekzoplanetami.

V stat'e daetsya obzor imenno astroseismologicheskih zadach i rezul'tatov missii. Osnovnye rezul'taty poluchayutsya v rezul'tate dolgih (chut' menee polugoda) nablyudenii odnoi ploshadki (razumeetsya, na nei mozhno izuchat' srazu neskol'ko ob'ektov). Tak budet izucheno okolo 50 yarkih zvezd. Krome etogo, provodyatsya korotkie (tri-chetyre nedeli) nablyudeniya. V hode korotkih nablyudenii budet izucheno chut' bol'shee kolichestvo ob'ektov.

Seichas missiya nahoditsya primerno v seredine svoego zhiznennogo cikla. Tak chto okonchatel'nye rezul'taty eshe vperedi.


arxiv:0811.15774 Issledovanie nizhnego predela na massu predsverhnovyh i massivnoi chasti sootnosheniya nachal'noi i konechnoi mass po dannym o belyh karlikah v rasseyannom skoplenii M35 (NGC2168) (Probing the lower mass limit for supernova progenitors and the high-mass end of the initial-final mass relation from white dwarfs in the open cluster M35 (NGC2168))
Authors: Kurtis A. Williams et al.
Comments: 16 pages, accepted for publication in the ApJ

Chasto mozhno prochest', chto "zvezdy, bolee legkie chem primerno 8-10 mass Solnca, v konce svoei evolyucii prevrashayutsya v belye karliki". A nel'zya li potochnee, da eshe po dannym pryamyh nablyudenii? Mozhno, konechno, tol'ko trudno.

Avtory polagayut, chto im udalos' dostatochno tochno opredelit' granicu, nizhe kotoroi voznikayut belye karliki. Issleduya 14 karlikov v rasseyannom skoplenii promezhutochnogo vozrasta (150-200 millionov let), oni dayut znachenie 5.1-5.2 massy Solnca. Udivitel'no nizkaya velichina! Pravda, dobavlyaya dannye po drugim skopleniyam i uchityvaya vsyakie raznye neopredelennosti, oni povyshayut predel do 7.1 solnechnoi massy.

Dannye po praroditelyam normal'nyh sverhnovyh dayut predel 9.5 mass Solnca (t.e. vyshe etoi velichiny zvezda vzryvaetsya). V itoge, vse ravno ostaetsya neopredelennost' otnositel'no togo, chto proishodit v promezhutke primerno 6 s hvostikom - 9 s hvostikom solnechnyh mass. Yasno, chto predel mozhet kak-to var'irovat'sya v zavisimosti ot metallichnosti i, vozmozhno, drugih parametrov.


arxiv:0811.1740 Shest' belyh karlikov s okolozvezdnymi silikatami (Six white dwarfs with circumstellar silicates)
Authors: M. Jura et al.
Comments: 21 pages, AJ in press

Okolo shesti belyh karlikov obnaruzheny diski s bol'shim soderzhaniem silikatov. Polagayut, chto eto rezul'tat prilivnogo razrusheniya asteroidov. Koli ono tak, to mozhno issledovat' sostav planet tipa Zemli, kotorye krutilis' vokrug zvezdy, prevrativsheisya v belyi karlik. Okazyvaetsya, chto tam, tak zhe kak i v Solnechnoi sisteme (naprimer, esli sravnivat' CI-hondrity i zemnuyu mantiyu), tverdye planety sostoyali iz porod, obednennyh uglerodom.


arxiv:0811.1972 GCRT J1742-3001: novyi radiotranzient v napravlenii centra Galaktiki (GCRT J1742-3001: A new radio transient towards the Galactic center)
Authors: Scott D. Hyman et al.
Comments: 19 pages, 3 figures, submitted to ApJ

Otkryt novyi radiotranzientnyi istochnik v 1 graduse ot galakticheskogo centra. Nablyudeniya provodilis' na nizkih chastotah (235 Mgc i 610 Mgc) na indiiskom teleskope GMRT. Istochnik nablyudalsya v 2006-7 godah na chastote 235 Mgc. Na 610 Mgc istochnik ne byl zaregistrirovan. V drugih diapazonah istochnik ne otozhdestvlen (v chastnosti, avtory ispol'zuyut dannye nablyudenii Swift v rentgene).

V techenie mesyaca istochnik uvelichival yarkost', dostignuv primerno 100 milliYanskih. Zatem potok umen'shilsya k mayu 2007 goda do 50 milliYanskih. V sentyabre 2007 i v 2008 g. obnaruzhit' istochnik uzhe ne udalos'. Takoe povedenie pohozhe na demonstrirovavsheesya drugim tranzientom v oblasti centra Galaktiki, kotoryi nablyudalsya v 1990-91 gg.

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.



Vypusk 197. 13-19 oktyabrya 2008

arxiv:0810.1780 Novye zavisimosti period-svetimost' i period-cvet dlya klassicheskii cefeid: III. Cefeidy malogo Magellanova Oblaka (New period-luminosity and period-color relations of classical cepheids: III. Cepheids of SMC)
Authors: A. Sandage, G.A. Tammann, B. Reindl
Comments: 9 pages, 10 figures, accepted for publication in A&A

Avtory analiziruyut dannye po cefeidam Malogo Magellanova oblaka, kotoroe po svoei metallichnosti otlichaetsya ot nashei Galaktiki i Bol'shogo Oblaka. Pokazano, chto zavisimosti period-svetimost' i period-cvet vedut sebya ne tak kak v Mlechnom puti i BMO. Avtory eshe raz ukazyvayut na to, chto nadezhdy poluchit' kakuyu-to edinuyu zavisimost' yavlyayutsya illyuziei, t.k. nado uchityvat' metallichnost', i utverzhdayut, chto chastichno 15-procentnoe otlichie ih (dlinnoi) shkaly ot poluchennoi v rezul'tate HST Key project svyazano kak raz s etim.


arxiv:0810.2238 Uglovye diametry gigantov Giad po izmereniyam CHARA (Angular diameters of the Hyades giants measured with the CHARA Array)
Authors: Tabetha S. Boyajian et al.
Comments: Accepted for publication in the Astrophysical Journal

Interferometr CHARA prodolzhaet izmeryat' zvezdy. Na etot raz rech' idet o chetyreh gigantah, vhodyashih v skoplenie Giady. Dlya kazhdoi zvezdy udaetsya opredelit' temperaturu i absolyutnuyu svetimost'. Nu a dal'she uzhe mozhno opredelyat' massu i tp. Voobshe, porazitel'no.


obzor arxiv:0810.2984 Perspektivy izucheniya zvezdnoi evolyucii i smerti v eru JWST (Prospects for studies of stellar evolution and stellar death in the JWST era)
Authors: Michel J. Barlow
Comments: 24 pages, 19 figures, to appear in "Astrophysics on the next decade: JWST and concurrent facilities"

Dovol'no bol'shoi obzor, posvyashennyi tomu, chto my smozhem uznat' v blizhaishie gody o rozhdenii, zhizni i smerti zvezd s pomosh'yu takih teleskopov kak Herschel, SOFIA, JWST.


Vypusk 196. 01-12 oktyabrya 2008

arxiv:0810.1429 Al'ternativnyi variant proishozhdeniya giperskorostnyh zvezd (An alternative origin for hypervelocity stars)
Authors: Mario G. Abadi et al.
Comments: Apj Letters, submitted, 8 pages, 4 figures

Napomnyu, chto v poslednie gody v galo Galaktiki byli otkryty zvezdy so skorost'yu dvizheniya neskol'ko soten kilometrov v sekundu. Standartnym ob'yasneniem yavlyaetsya dinamicheskoe vzaimodeistvie so sverhmassivnoi chernoi dyroi v centre Galaktiki. V rezul'tate vzaimodeistviya zvezda mozhet byt' vybroshena s bol'shoi skorost'yu.

V dannoi stat'e avtory predlagayut sleduyushuyu al'ternativu. Ih modelirovanie pokazyvaet, chto razrushenie karlikovoi galaktiki-sputnika v central'noi oblasti Mlechnogo Puti takzhe mozhet privesti k poyavleniyu zvezd s ochen' bol'shimi skorostyami. Avtory pokazyvayut, chto v blizhaishem budushem mozhno budet vyyasnit' kakoi iz scenariev veren, t.k. nekotorye ih predskazaniya ochen' razlichny. Naprimer, v scenarii s galaktikoi-sputnikom budut oblasti, v kotoryh giperskorostnyh zvezd budet gorazdo bol'she.


Vypusk 195. 12-30 sentyabrya 2008

arxiv:0809.2518 Vnegalakticheskie ogranicheniya na nachal'nuyu funkciyu mass (Extragalactic Constraints on the Initial Mass Function)
Authors: Stephen M. Wilkins, Andrew M. Hopkins, Neil Trentham, Rita Tojeiro
Comments: 6 pages, 5 figures, accepted to MNRAS

Rech' idet o zvezdnoi funkcii mass. Avtory pytayutsya ponyat', kak nashi dannye po nachal'noi funkcii mass zvezd mozhno uvyazat' s kosmologicheskimi dannymi po istorii zvezdoobrazovaniya, poskol'ku v etom dele est' nestykovki.


Vypusk 194. 01-11 sentyabrya 2008

arxiv:0809.0206 VLT zaregistriroval krasnyi gigant - praroditelya sverhnovoi 2008bk, imevshei tip IIP (VLT detection of a red supergiant progenitor of the type IIP supernova 2008bk)
Authors: S. Mattila, S.J. Smartt, J.J. Eldridge, J.R. Maund, R.M. Crockett, I.J. Danziger
Comments: 4 pages, 2 figures, submitted to ApJ letters

Na snimkah, sdelannyh VLT, udalos' rassmotret' zvezdu-praroditelya sverhnovoi 2008bk. Sverhnovaya imela tip IIP. Izuchenie praroditelya pokazalo, chto on imel nachal'nuyu massu ot 7.5 do 9.5 mass Solnca.

Drugaya interesnaya rabota po praroditelyam sverhnovyh - arxiv:0809.0236. V nei avtory issleduyut raspredelenie sverhnovyh v galaktikah, sravnivaya ego s polozheniem oblastei zvezdoobrazovaniya. Sverhnovye tipa II huzhe vsego otslezhivayut zvezdoobrazovaniya. Tipa Ic - luchshe vsego. Iz etogo avtory delayut vyvod, chto posledovatel'nost' II-Ib-Ic otrazhaet rost massy zvezd-praroditelei.

Eshe odna stat'ya arxiv:0809.0403 posvyashena nablyudatel'nym ogranicheniyam na praroditelei SN IIP. Minimal'naya massa praroditelei etih sverhnovyh 7-9.5 mass Solnca.


obzor arxiv:0809.0407 Blizhaishaya OV associaciya: Skorpion-Centavr (Sco OB2) (The Nearest OB Association: Scorpius-Centaurus (Sco OB2))
Authors: Thomas Preibisch, Eric Mamajek
Comments: 50 pages, Chapter for the "Handbook of Star Forming Regions", Vol. II: The Southern Sky, Bo Reipurth, ed

Svedeny voedino vse dannye po samoi blizkoi k nam associacii Sco OB2. Razumeetsya, poskol'ku rech' idet o blizhaishei associacii, to ona ispol'zuetsya kak nekotoryi poligon dlya izucheniya podobnyh obrazovanii. Ona sostoit iz treh grupp raznyh vozrastov (5, 16 i 17 millionov let). Blagodarya blizosti mozhno izuchat' ne tol'ko massivnye zvezdy.


arxiv:0809.0510 Novyi klass moshnyh tranzientov i pervaya peprepis' ih massivnyh praroditelei (A New Class of Luminous Transients and A First Census of Their Massive Stellar Progenitors)
Authors: Todd A. Thompson et al.
Comments: 21 pages, emulateapj, 11 figures, 3 tables; submitted to ApJ

Nedavno bylo obnaruzheno dva sobytiya, kotorye po vsei vidimosti yavlyayutsya sverhnovymi, no ih zvezdna velichina byla neskol'ko men'she. Opredeleny zvezdy-praroditeli etih vzryvov. Avtory polagayut, chto vo-pervyh, eti sobytiya formiruyut novyi tip zvezdnyh vzryvov, sostavlyayushii kak minimum bolee 10 procentov ot vseh sverhnovyh, svyazannyh s kollapsom yadra. Vo-vtoryh, oni delayut eshe bolee interesnyi vyvod.

Delo v tom, chto vokrug zvezd-praroditelei etih vzryvov ochen' mnogo pyli. My znaem takie zvezdy, no ih ochen' malo. T.e., esli prosto vzorvat' izvestnye stol' zapylennye zvezdy, to temp vzryvov budet slishkom nizkim. Otsyuda avtory delayut sleduyushii vyvod. Za neskol'ko tysyach let do vzryva mnogoe massivnye zvezdy (mnogie, no ne vse, dazhe, vidimo, men'shinstvo, no vse ravno rech' idet kak minimum o desyati procentah, a skoree neskol'ko bol'she) obrazuyut vokrug sebya mnogo-mnogo pyli.

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.


arxiv:0809.1678 Udarnaya volna ot vzryva Eta Kilya 1843 goda (A Blast Wave from the 1843 Eruption of Eta Carinae)
Authors: Nathan Smith
Comments: 10 pages, 3 color figs, supplementary information. Accepted by Nature

V 1843 godu ot yarkoi zvezdy Ety Kilya nablyudalas' moshnaya vspyshka. V stat'e avtor rasskazyvaet o tom, chto im obnaruzheno bystro dvigayusheesya veshestvo (3500-6000 km v sek), svyazannoe s etoi vspyshkoi. Do etogo ranblyudalis' lish' sushestvenno men'shie skorosti. Novye dannye govoryat v pol'zu togo, chto vydelenie energii proizoshlo gluboko pod poverhnost'yu. A ran'she schitalos', chto nablyudaemyi razlet veshestva svyazan lish' s rezkim usileniem zvezdnogo vetra.


miniobzor arxiv:0809.1800 Obrazovanie i evolyuciya kataklizmicheskih peremennyh (Formation and Evolution of Cataclysmic Variables)
Authors: H. Ritter
Comments: 14 pages, to appear in Mem. Soc. Astron. Italiana, Proceedings of the School of Astrophysics "Francesco Lucchin";

Nebol'shoi obzor po teme.


Vypusk 193. 15-31 avgusta 2008

arxiv:0808.1899 Vspyhivayushii radiotranzient v napravlenii galakticheskogo centra (A bursting radio transient in the direction of the galactic center)
Authors: Paul S. Ray et al.
Comments: 11 pages, 2 figures, to appear in proceedings of "Bursts, pulses and flickering: wide-field monitoring of the dynamic radio sky"

GCRT J1745-3009 - interesnyi i neponyatnyi radiotranzient, otkrytyi neskol'ko let nazad. Obsuzhdalos' neskol'ko raznyh modelei istochnika, i mozhno pridumat' novye (naprimer, odinochnye neitronnye zvezdy na ekzoticheskih stadiyah, superezhektor v dvoinoi sisteme i tp.). Avtory opisyvayut dannye po etomu istochniku, obsuzhdayut nekotorye modeli i rassuzhdayut, chto mozhno nadeyat'sya uznat' v budushem.


arxiv:0808.2039 Izmerenie magnitnyh polei O-zvezd s pomosh'yu FORS1 na VLT (Magnetic field measurements of O stars with FORS1 at the VLT)
Authors: S. Hubrig et al.
Comments: 8 pages, 4 figures, 3 tables, accepted to A&A

Avtory privodyat novye dannye po izmereniyam magnitnyh polei u massivnyh zvezd. Osnovnoi vyvod avtorov v tom, chto po vsei vidimosti uporyadochennye krupnomasshtabnye polya ne slishkom chasto vstrechayutsya u O-zvezd.


arxiv:0808.2469 Obzor giperskorostnyh zvezd na MMT (MMT Hypervelocity Star Survey)
Authors: Warren R. Brown, Margaret J. Geller, Scott J. Kenyon
Comments: 10 pages, submitted to ApJ

Esli vy eshe ne slyshali o giperskorostnyh zvezdah, to eto vash shans, ibo v stat'e ne tol'ko privodyatsya novye rezul'taty, no i daetsya horoshee opisanie etoi oblasti astronomii.

Giperskorostnye zvezdy nachali otkryvat' ne tak davno - okolo 3-4 let nazad. Oni imeyut skorosti poryadka neskol'kih soten km v sek - vyshe skorosti ubeganiya iz Galaktiki (prenebrezhem rol'yu galo). T.e., zvezdy nado bylo kak-to razognat'. Eto ne malomassivnye malometallichnye zvezdy galo. Naibolee veroyatnym schitaetsya, chto zvezdy byli vybrosheny iz central'noi oblasti Galaktiki posle vzaimodeistviya s central'noi sverhmassivnoi chernoi dyroi.

V stat'e avtory privodyat dannye po svezheotkrytym zvezdam etogo tipa. Novye rezul'taty prakticheski udvaivayut ih chislo. Sootvetstvenno, mozhno s bol'shim osnovaniem navodit' vsyakuyu statistiku i obsuzhdat' proishozhdenie i tp.


miniobzor arxiv:0808.3136 Astroseismologiya i solnechno-zvezdnye svyazi (Astroseismology and the Solar-Stellar Connection)
Authors: Travis S. Metcalfe
Comments: 10 pages, 7 figures, Proc. SOHO XXI/GONG 2008

V sleduyushem godu budet zapushen sputnik KEPLER. Eto budet pervaya specializirovannaya missiya, sposobnaya otkryvat' planety tipa Zemli okolo zvezd tipa Solnca. Avtor daet obzor proekta, a takzhe obsuzhdaet, kak s pomosh'yu metodov astroseismologii budut opredelyat'sya parametry zvezd.


Vypusk 192. 01-14 avgusta 2008

arxiv:0808.0063 GRAVITY: dostat' gorizont sobytii Sgr A* (GRAVITY: getting to the event horizon of Sgr A*)
Authors: F. Eisenhauer et al.
Comments: 13 pages, 11 figures, to appear in the conference proceedings of SPIE Astronomical Instrumentation, 23-28 June 2008, Marseille, France

Dlya VLT razrabatyvaetsya special'nyi pribor, kotoryi pomozhet nablyudat' dvizhenie zvezd i gaza v neposredstvennoi blizosti ot gorizonta sobytii v istochnike Sgr A* - sverhmassivnoi chernoi dyre v centre nashei Galaktiki. Dlya realizacii potrebuetsya ne tol'ko sozdat' novye instrumenty, no i zadeistvovat' vsyu mosh' interferometricheskoi sistemy VLT.

Razumeetsya, nikto ne delaet pribor "pod odin ob'ekt", i v stat'e avtory rassmatrivayut i drugie vozmozhnye oblasti prilozhenii. Pribor nachnet rabotat' v 2013 godu (seichas ego sozdanie polnost'yu odobreno).


arxiv:0808.0932 Pervye izobrazheniya zatmennoi vzaimodeistvuyushei dvoinoi beta Liry (First Resolved Images of the Eclipsing and Interacting Binary Beta Lyrae)
Authors: M. Zhao et al.
Comments: 13 Pages, 3 Figures; Accepted by ApJL

S pomosh'yu opticheskih interferometrov vpervye udalos' v detalyah razglyadet' sistemu betu Liry, razreshiv ee na dva komponenta.

Izobrazhenie polucheno s pomosh'yu sistemy CHARA Array. Vidna zvezda donor (sleva) i disk vokrug vtorogo komponenta. Vidno, chto donor slegka vytyanut, t.e. vpervye udalos' rassmotret' napryamuyu iskazhenie formy vo vremya zapolneniya polosti Rosha.

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.


arxiv:0808.1849 Obshii metod ocenki parametrov zvezd po dannym fotometrii (A general method of estimating stellar astrophysical parameters from photometry)
Authors: A.N. Belikov, S. Roser
Comments: 14 pages, 20 figures, accepted by A&A

Seichas est' mnogo horoshih obzorov neba s fotometricheskimi dannymi v shirokih polosah. Iz etih dannyh mozhno bylo by poprobovat' ocenit' parametery zvezd (effektivnye temperatury, metallichnost', silu tyazhesti), no ne vse tak prosto - est' mezhzvezdnoe veshestvo, kotoroe privodit k pokrasneniyu. Avtory predlagayut metod, kotoryi, po ih utverzhdeniyu, horosho spravlyaetsya s etoi neprostoi i aktual'noi zadachei.

Sm. takzhe arxiv:0808.1848 ob absolyutnoi kalibrovke zvezd glavnoi posledovatel'nosti tonkogo diska po nablyudeniyam v optike i blizhnem IK.


Vypusk 191. 22-31 iyulya 2008

arxiv:0807.3049 Mnozhestvennye kol'ca vokrug golubyh sverhgigantov (Multiple ring nebulae around blue supergiants)
Authors: S.M. Chita et al.
Comments: Accepted for publication in A&A Letters

Vzaimodeistvie zvezdnyh vetrov, istekayushih na raznyh stadiyah ot evolyucioniruyushih massivnyh zvezd, mozhet porozhdat' prichudlivye struktury, poskol'ku geometriya i drugie parametry vetrov v razlichnye momenty zhizni zvezdy razlichayutsya. Avtory stroyat model' takih vetrov. V chastnosti, im udaetsya ob'yasnit' kartinu kolec vokrug praroditelya sverhnovoi 1987A bez privlecheniya dvoistvennosti.


obzor arxiv:0807.4870 Prilivnaya dissipaciya v dvoinyh sistemah (Tidal dissipation in binary systems)
Authors: Jean-Paul Zahn
Comments: 24 pages, 11 figures, lecture notes of "Stellar Physics Summer School 2005", on "Tidal effects in stars, planets and disks", EAS Publication Series 29, 2008

Svezhaya lekciya odnogo iz klassikov. Ona posvyashena prilivnoi dissipacii v tesnyh dvoinyh sistemah. Zvezdy vozbuzhdayut drug v druge prilivy. Dalee, v zavisimosti ot stroeniya zvezdy (vneshnyaya konvektivnaya, ili vneshnyaya luchistaya obolochka) energiya prilivov budet dissipirovat'. Eto vse ochen' vazhno dlya raschetov evolyucii dvoinyh sistem.


miniobzor arxiv:0807.4929 Tochnoe izmerenie parametrov prohozhdenii planet (Measuring accurate transit parameters)
Authors: Joshua N. Winn
Comments: submitted to Proc. IAU Symp. No. 253, "Transiting Planets", eds. F. Pont et al., May 19-23, 2008, Cambridge, MA [11 pages]

Pri prohozhdenii planety po disku zvezdy mozhno izmeryat' mnogo parametrov i nablyudat' mnogo raznyh effektov. V tablice v svoem nebol'shom obzore Vinn perechislyaet 26 parametrov i effektov. Chast' iz nih uzhe izmeryayut, chast' - budut izmeryat' v nedalekom budushem.

Obzor nebol'shoi i ochen' ponyatnyi. Ne vse effekty, i ne vse puti izmereniya parametrov opisany, no dlya vseh dany ssylki. A te, kotorye opisany, opisany ochen' horosho.


arxiv:0807.5050 Sil'nye vzryvy pri z=0? (Powerful explosions at Z=0 ?)
Authors: S. Ekstrom, G. Meynet, R. Hirschi, A. Maeder
Comments: 5 pages, 5 figures, to appear in the IAU Symposium 255, "Low-Metallicity Star Formation: From the First stars to Dwarf Galaxies"

Avtory pokazyvayut, chto zvezdy s nulevoi metallichnost'yu (v dannom sluchae z=0 oznachaet nulevuyu metallichnost', a ne krasnoe smeshenie) mogut davat' normal'nye vzryvy sverhnovyh. Dlya etogo neobhodimo, chtoby zvezdy dostatochno bystro vrashalis'. Obychno polagayut, chto massivnye zvezdy bez metallov porozhdayut ochen' tyazhelye uglerodno-kislorodnye yadra i pryamo kollapsiruyut v chernye dyry. Vrashenie mozhet izmenit' kartinu. Esli zvezdy pokoleniya III mogut davat' sverhnovye, to eto vazhno, t.k. vliyat na rannee obogashenie vselennoi tyazhelymi elementami.

O vrashenie malometallichnyh zvezd sm. takzhe arxiv:0807.5061


Vypusk 190. 09-21 iyulya 2008

arxiv:0807.1507 Poisk otozhdestvleniya GCRT J1745-3009 v blizhnem IK diapazone (A search for the Near-infrared Counterpart to GCRT J1745-3009)
Authors: D.L.Kaplan et al.
Comments: 10 pages, 5 figures, Accepted for publication in the Astrophysical Journal

GCRT J 1745-3009- zagadochnyi tranzientnyi radioistochnik, otkrytyi okolo 6 let nazad. On nahoditsya v napravlenii galakticheskogo centra. Ot nego bylo zaregistrirovano 7 vspyshek v radio (na 300 Mgc), prichem pervye 5 vspyshek pokazali periodichnost' okolo 77 minut. Chto eto za ob'ekt - neizvestno. Eto mozhet byt' blizkii korichnevyi karlik, ili dalekaya sistema s neitronnoi zvezdoi. Nado iskat' otozhdestvlenie v drugih diapazonah, chto avtory i delayut. Rezul'tat - nulevoi. T.e. nichego ne naideno. No eto ne znachit, chto vse bestolku. Po suti, avtory isklyuchili vozmozhnost' togo, chto eto blizkaya malomassivnaya zvezda ili belyi karlik.


arxiv:0807.2476 Dve ochen' yarkie WN zvezdy v oblasti centra Galaktiki s okolozvednym izlucheniem gaza i pyli (Two extremely luminous WN stars in the Galactic center with circumstellar emission from dust and gas)
Authors: A. Barniske, L.M. Oskinova, W.-R. Hamann
Comments: accepted to A&A

Upominayu etu stat'yu v osnovnom v svyazi s tem, chto rezul'tat poyavilsya na mnogih novostnyh lentah. Po nauke konechno interesno ne to, chto eto odni iz samyh moshnyh zvezd v Galaktike, a to, chto nablyudaetsya pyl' vblizi WN zvezd.


arxiv:0807.2522 Guide star katalog vtorogo pokoleniya: opisanie i parametry (The Second-generation Guide Star Catalogue: Description and Properties)
Authors: B.M. Lasker et al.
Comments: 52 pages, 33 figures, to be published in AJ

GSC-I (Guide Star Catalogue - I) byl sozdan dlya nuzhd Kosmicheskogo teleskopa. Seichas vypushena vtoraya versiya. Vo vtoroi versii kataloga pochti milliard ob'ektov!


Vypusk 189. 24 iyunya - 08 iyulya 2008

arxiv:0806.3979 Sluzhba po obzoram tranzitnyh planet NStED (The NStED Exoplanet Transit Survey Service)
Authors: K. von Braun et al.
Comments: To appear in the Proceedings of the 253rd IAU Symposium: "Transiting Planets", May 2008, Cambridge, MA. 4 pages, 2 figures

Opisana sluzhba (i baza dannyh) NStED (NASA/IPAC/MSC Star and Exoplanet Database). Privodyatsya dannye po 140 000 yarkim blizkim zvezdam, po izvestnym planetam i tp. Razumeetsya, baza budet rasti, osobenno posle zapuska novyh sputnikov, special'no prednaznachennyh dlya poiska ekzoplanet.


miniobzor arxiv:0806.4063 Evolyuciya massivnyh zvezd: ot rannih dnei vselennoi do segodnyashnego dnya (Massive star evolution: from the early to the present day Universe)
Authors: Georges Meynet, Sylvia Ekstrom, Cyril Georgy, Andre Maeder, Raphael Hirschi
Comments: 11 pages, 7 figures, IAU Symp. 252, L. CUP, Deng, K.L. Chan, C. Chiosi, eds

V zhizni massivnyh zvezd bol'shuyu rol' igrayut vrashenie i zvezdnyi veter. Oba eti effekta dostatochno slozhny dlya ucheta, oni sil'no menyayutsya s izmeneniem metallichnosti. Mnogoe tam prosto eshe neyasno. Avtory pytayutsya v otnositel'no nebol'shom obzore ochertit' osnovnye evolyucionnye effekty, svyazannye s vrasheniem massivnyh zvezd i ih zvezdnym vetrom.


miniobzor arxiv:0807.0445 Svoistva zvezd - praroditelei gamma-vspleskov (Properties of Gamma-Ray Burst Progenitor Stars)
Authors: Pawan Kumar, Ramesh Narayan, Jarrett L. Johnson
Comments: 12 pages, Science in press

Avtory pytayutsya dat' obzor svoistv massivnyh zvezd, kotorye porozhdayut v konce svoei zhizni dlinnye gamma-vspleski. Razumeetsya, nikakoi yasnosti tut net, i avtory skoree pytayutsya prosto chto-to ponyat' na osnove standartnoi modeli i izvestnyh dannyh o poslesvecheniyah vspleskov.

Kstati, o mehanizme central'noi mashiny gamma-vspleskov mozhno posmotret' korotkii obzor arxiv:0807.0747.


Vypusk 188. 10-23 iyunya 2008

miniobzor arxiv:0806.1317 QPO v kataklizmicheskih peremennyh: obzor (QPOs in CVs: An executive summary)
Authors: Brian Warner, Patrick A. Woudt
Comments: 10 pages, 7 figures, to appear in Cool discs, hot flows: The varying faces of accreting compact objects' (AIP Conf. Series)

Daetsya obzor po razlichnym kvaziperiodicheskim processam, nablyudaemym u kataklizmicheskih peremennyh. Krome razlichnyh processov, svyazannyh s diskovoi akkreciei, v takih sistemah dobavlyaetsya vozmozhnost' nalichiya neradial'nyh pul'sacii belyh karlikov.


obzor arxiv:0806.2573 Pul'siruyushie belye karliki i precizionnaya astroseismologiya (Pulsating White Dwarf Stars and Precision Asteroseismology)
Authors: D.E. Winget, S.O. Kepler
Comments: 70 pages, 11 figures, to be published in Annual Review of Astronomy and Astrophysics 2008

Bol'shoi obzor po pul'saciyam belyh karlikov.

Poskol'ku obzor bol'shoi, to tam vsemu nashlos' mesto: i istoricheskomu vvedeniyu, i bazovomu opisaniyu fiziki belyh karlikov (zhurnal Annual Review of Astronomy and Astrophysics rasschitan skoree na nablyudatelei, chem teoretikov), i poyasneniyu togo zachem vse eto nuzhno (belye karliki - eto ochen' udobnye "relikty", po kotorym mozhno otslezhivat' raznye etapy evolyucii Galaktiki).


miniobzor arxiv:0806.2575 Chto Gaia rasskazhet nam o galakticheskom diske? (What will Gaia tell us about the Galactic disk?)
Authors: C.A.L. Bailer-Jones
Comments: Proceedings of IAU 254 "The Galaxy disk in a cosmological context", Copenhagen, June 2008, invited talk, 8 pages

Koroten'kii obzor, posvyashennyi budushemu astrometricheskomu sputniku Gaia i ozhidaemym rezul'tatam po svoistvam diska nashei Galaktiki. Yasno, chto poluchiv milliard tochnyh izmerenii polozhenii zvezd, sputnik sil'no prodvinet nashe ponimanie, tem ne menee interesno posmotret' detali.


arxiv:0806.2681 Annigilyaciya temnogo veshestva v zvezdah populyacii III (Dark Matter annihilations in Pop III stars)
Authors: Marco Taoso, Gianfranco Bertone, Georges Meynet, Sylvia Ekstrom
Comments: 4 pages, 4 figures

Zvezdy populyacii III obrazuyutsya iz veshestva nulevoi metallichnosti v galo temnoi materii na z~20. Razumeetsya, kakoe-to kolichestvo chastic temnogo veshestva okazyvaetsya vnutri zvezd. Eti chasticy mogut annigilirovat' drug s drugom, i lyudi davno zadumalis' nad vozmozhnymi posledstviyami.

Na pal'cah posledstviya ochen' prosty. Vydelyaetsya dopolnitel'naya energiya, povyshaetsya temperatura. Zvezda (ili protozvezda) slegka rasshiryaetsya, chto ponizhaet temp yadernyh reakcii v zvezde, t.e. formirovanie zvezdy otkladyvaetsya ili zhe zvezda budet zhit' dol'she, poskol'ku medlennee rashoduet "goryuchee". Kachestvenno vse yasno, vopros s kolichestvennymi harakteristikami.

Avtory ispol'zuyut odin iz luchshih v mire kodov po raschetu zvezdnoi evolyucii, chtoby posmotret' naskol'ko mozhno uvelichit' zhizn' zvezdy pri raznoi plotnosti temnogo veshestva. Imenno plotnost' chastic temnoi materii okazyvaetsya klyuchevym parametrom. Esli etih chastic nabrat' dostatochno mnogo, to - o chudo! - massivnaya pervozvezda mozhet voobshe dozhit' do nashih dnei. Odnako avtory ne issleduyut naskol'ko chasto takaya plotnost' budet nabirat'sya. Skoree vsego eto dostatochno redkaya situaciya. No kak bylo by interesno naiti ryadom massivnuyu zvezdu, obrazovavshuyusya, kogda eshe i galaktik-to nikakih ne bylo!

Sm. takzhe stat'yu arxiv:0806.2662, gde avtory provodyat analogichnoe issledovanie i prihodyat k shozhim vyvodam.


arxiv:0806.2815 Ochen' massivnaya dvoinaya NGC3603-A1 (The very massive binary NGC3603-A1)
Authors: O. Schnurr, A. F. J. Moffat, N. St-Louis, J. Casoli, A.-N. Chene
Comments: 5 pages, 4 figures; accepted for MNRAS Letters

V stat'e rasskazyvaetsya ob obnaruzhenii dvoinoi, sostoyashei iz dvuh ochen' massivnyh zvezd. Esli ocenki massy verny, to eto prosto samaya massivnaya dvoinaya: 116 (+/-31) i 89 (+/-16) mass Solnca. Prichem, bolee massivnyi komponent pary pretenduet na zvanie samoi massivnoi zvezdy.

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.


obzor arxiv:0806.3019 Galakticheskie i vnegalakticheskie rasstoyaniya: proekt Peremennye zvezdy (Galactic and Extragalactic Distance Scales: The Variable Star Project)
Authors: Michael W. Feast
Comments: 5 pages, For Proc. Middle-East Africa Regional IAU Meeting, Cairo 2008

Daetsya kratkaya svodka sostoyaniya del v opredelenii rasstoyanii po razlichnym tipam peremennyh zvezd (razlichnye cefeidy i rodstvennye im zvezdy, miridy). Takzhe privodyatsya ocenki rasstoyaniya do centra Galaktiki i postoyannaya Habbla, poluchennye v ramkah proekta.


arxiv:0806.3089 Porazitel'nye razlichiya mezhdu molodymi zvezdami-bliznecami v dvoinoi sisteme (Surprising dissimilarities in a newly formed pair of 'identical twin' stars)
Authors: Keivan G. Stassun et al.
Comments: 23 pages, Published in Nature, 19 June 2008

Avtory issleduyut paru molodyh zvezd. Massa komponent dvoinoi identichna s tochnost'yu okolo 2 procentov (0.4 massy Solnca). A vot temperatury, radiusy i svetimosti razlichayutsya gorazdo sil'nee. Avtory polagayut, chto edinstvennym razumnym ob'yasneniem yavlyaetsya raznyi vozrast dvuh komponentov dvoinoi. Vot takoi vot "paradoks bliznecov".

Situaciya udivitel'na. Obychno polagayut, chto vozrast zvezd v dvoinoi sisteme odinakov (osobennoe, kogda massy primerno ravny). Eto predpolozhenie dazhe ispol'zuetsya pri kalibrovkah-normirovkah. A tut takoe otkrytie!

Sistema yavlyaetsya zatmennoi dvoinoi. Vozrast okolo milliona let (eto samaya molodaya zatmennaya sistema so zvezdami-bliznecami). Nablyudeniya spektrov vysokogo razresheniya byli provedeny na teleskope Hobbi-Eberli.

Obsudit' v ZhZh-soobshestve ru_astroph
Obsudit' na Astroforume v Nauchnoi panorame.


Vypusk 187. 01-09 iyunya 2008

arxiv:0806.0672 O proishozhdenii O-zvezd polya (On the origin of field O-type stars)
Authors: E. Schilbach, S. Roeser
Comments: 12 pages, 9 figures, 1 table, accepted for publication in Astronomy and Astrophysics

Molodye massivnye zvezdy spektral'nogo klassa O nablyudayutsya, kak v skopleniyah i associaciyah, tak i v "pole Galaktiki". Otnositel'no poslednih vse vremya stoit vopros o tom, obrazovalis' li oni po-odinochke, ili vse-taki vhodili v sostav kakih-to grupp massivnyh zvezd. Regulyarno poyavlyayutsya stat'i, posvyashennye etomu voprosu.

Avtory pytayutsya otsledit' traektorii O-vezd polya, chtoby ponyat', ne vyleteli li oni iz kakih-to izvestnyh skoplenii ili associacii. Iz 93 issledovannyh zvezd polya dlya 73 udalos' naiti vozmozhnyi trek, nachinayushiisya v skoplenii. T.o., lish' dlya 10 procentov O-zvezd ne udaetsya naiti materinskoe skoplenie. Eto, pravda, ne oznachaet, chto oni rodilis' v odinochestve. Prosto, vozmozhno, za neskol'ko millionov let nebol'shaya gruppa zvezd uspela raspast'sya, i my teper' ne mozhem ee identificirovat'.


Vypusk 186. 16-31 maya 2008

katalog arxiv:0805.4517 Katalog dvoinyh zvezd s hromosfernoi aktivnost'yu (tret'ya versiya) (A catalog of chromospherically active binary stars (third edition))
Authors: Z. Eker et al.
Comments: 5 pages, including 2 figures and 3 tables, accepted for publication in MNRAS

Sam katalog, konechno zhe, dostupen po seti na saite CDS, a v stat'e dano kratkoe opisanie. V katalog vhodit 409 sistem, iz kotoryh polovina - novye otozhdestvleniya.


katalog arxiv:0805.4736 Novyi katalog zvezd s bol'shimi sobstvennymi dvizheniyami (A New All-Sky Catalog of Stars with Large Proper Motions)
Authors: Sebastien Lepine et al.
Comments: 5 pages, To appear in proceedings of IAU Symposium No. 248 - A Giant Step: from Milli- to Micro-arcsecond Astrometry, Shangai : China (2007)

Avtory kratko opisyvayut novyi katalog zvezd s bol'shimi (>0.15 sekund v god) sobstvennymi dvizheniyami. Katalog pokryvaet vse nebo. Pravda, avtory ne opisyvayut, gde katalog skachat'.


baza dannyh arxiv:0805.4749 KADoNiS- karlsruevskaya astrofizicheskaya baza dannyh po nukleosintezu v zvezdah (KADoNiS- The Karlsruhe Astrophysical Database of Nucleosynthesis in Stars)
Authors: I. Dillmann, M. Heil, F. Kppeler, R. Plag, T. Rauscher, F.-K. Thielemann
Comments: 5 pages Conference Proccedings "CGS12", Notre Dame/ USA (4.-9. Sep. 2005)

A vot eti avtory privodyat ssylku na svoyu bazu. I opisyvayut ee v neskol'kih zametkah (arxiv:0805.4755, arxiv:0805.4747, arxiv:0805.4756). V baze privodyat eksperimental'nye dannye po secheniyam, aktual'nym dlya raschetov s- i p-processov.


Vypusk 185. 01-15 maya 2008

arxiv:0805.0140 Zvezdnaya ekzotika v 47 Tukana (Stellar Exotica in 47 Tucanae)
Authors: Christian Knigge et al.
Comments: 28 pages, 22 figures, 1 table, accepted for publication in ApJ

Avtory podrobno predstavlyayut rezul'taty nablyudeniya skopleniya 47 Tukana, provedennyh v UF diapazone na Habble. Naideno mnogo ekzoticheskih ob'ektov. Tak vpervye obnaruzhena para goluboi brodyaga+belyi karlik, naidena (v dvoinoi sisteme) goryachaya malomassivnaya zvezda (eto, vidimo, "obodrannyi" gigant), a takzhe naiden gelievyi belyi karlik bez millisekundnogo pul'sara v kachestve soseda po dvoinoi.


Vypusk 184. 21-30 aprelya 2008

arxiv:0804.3593 Polyarnaya kak cefeida vozvrashaetsya: 4.5 goda monitoringa s Zemli i iz kosmosa (Polaris the Cepheid returns: 4.5 years of monitoring from ground and space)
Authors: H. Bruntt et al.
Comments: Accepted by ApJ. 8 pages. Quality of figures 1+3+7 degraded

V techenie dolgogo vremeni nablyudeniya pokazyvali, chto amplituda pul'sacii Polyarnoi zvezdy umen'shalas'. Eto svyazyvali s ee evolyuciei, dvizheniem k krayu oblasti nestabil'nosti. Odnako novye nablyudeniya, predstavlyaemye v dannoi stat'e, pokazyvayut, chto pul'sacii snova priobretayut bol'shuyu amplitudu. Avtory polagayut, chto amplituda menyaetsya ciklicheskim obrazom.


Vypusk 183. 01-20 aprelya 2008

obzor arxiv:0804.0019 Zvezdnoe galo Galaktiki (The stellar halo of the Galaxy)
Authors: Amina Helmi
Comments: Astronomy & Astrophysics Reviews, in press. 46 pages, 16 figures. Full-resolution version available at this http URL

Izuchenie galo galaktik vazhno ne tol'ko samo po sebe, ved' galo nesut na sebe otpechatok istorii formirovaniya galaktiki. Znachit, izuchaya galo, my mozhem uznavat' chto-to novoe o tom, kak dannaya konkretnaya galaktika obrazovyvalas'.

V obzore opisyvayutsya nashi sovremennye znaniya o strukture, kinematike i himicheskom sostave zvezdnogo galo nashei Galaktiki. Sootvetsvenno, zatragivayutsya i voprosy interpretacii etih dannyh.

V poslednie gody blagodarya obzoram tipa SDSS udalos' uznat' mnogo novogo o strukture galo. Tam obnaruzheny raznoobraznye struktury, yavlyayushiesya rudimentami proshlyh pogloshenii galaktikoi karlikovyh sputnikov. Krome togo, razvivaetsya chislennoe modelirovaniya formirovaniya i evolyucii (vklyuchaya himicheskuyu) Galaktiki. Vse eto otrazheno v obzore.

obzor arxiv:0804.0250 Samye sil'nye magnity v kosmose: istochniki myagkih povtoryayushihsya gamma-vspleskov i anomal'nye rentgenovskie pul'sary (The strongest cosmic magnets: Soft Gamma-ray Repeaters and Anomalous X-ray Pulsars)
Authors: Sandro Mereghetti
Comments: Submitted to Astromomy and Astrophysics Review (57 pages, 19 figures, 6 tables)

Bol'shoi podrobnyi obzor po istochnikam myagkih povtoryayushihsya gamma-vspleskov i anomal'nym rentgenovskim pul'saram. T.e., po osnovnym kandidatam v magnitary.


miniobzor arxiv:0804.0644 Galaktiki so zvezdoobrazovaniem na z>5 (Star Forming Galaxies at z > 5)
Authors: Yoshi Taniguchi
Comments: 8 pages, no figure, Proceeding of IAU Symposium 250, in press

Hotya obzor napisan na ves'ma "yaponskom angliiskom" s massoi opechatok, tem ne menee, v nem ponyatnym obrazom summirovany popytki poiska galaktik na bol'shih krasnyh smesheniyah. Seichas dobralis' do z~7. Vse eto blagodarya, v osnovnom, poisku v opticheskom diapazone. Chtoby dvigat'sya dal'she, nuzhno nablyudat' v blizhnem IK. No tut poka est' tehnicheskie trudnosti. Poetomu, polagaet avtor, nuzhno zhdat' instrumentov sleduyushego pokoleniya.


obzor arxiv:0804.0683 Akkrecionye diski, malomassivnye protozvezdy i planety: issledovanie roli magnitnyh polei v zvezdoobrazovanii (Accretion discs, low-mass protostars and planets: probing the impact of magnetic fields on stellar formation)
Authors: J. F. Donati et al.
Comments: 20 pages, Proceedings of CNRS/PNPS astrophysical school on "stellar magnetic fields", EAS Publications Series

Avtory rassmatrivayut progress v ponimanii roli magnitnogo polya v processe obrazovaniya zvezd. V pervuyu ochered' zdes' vazhny pryamye nablyudeniya magnitnyh polei (posmotrite zamechatel'nye kartinki, na kotoryh pokazany struktury magnitnogo polya neskol'kih zvezd tipa T Tel'ca). Zatem sushestvenny chislennye modeli. No, kak obychno, "mnogoe sdelano, no mnogoe eshe predstoit". V poslednei chasti obzora avtory obsuzhdayut nereshennye problemy i vozmozhnye puti ih razresheniya. Zdes' takzhe est' novye nablyudatel'nye programmy, i est' plany po provedeniyu novyh detal'nyh simulyacii.


miniobzor arxiv:0804.0711 Evolyuciya Ap zvezd (The evolution of Ap stars)
Authors: P. North, J. Babel, D. Erspamer
Comments: 11 pages, 6 figures Journal-ref: Contrib. Astron. Obs. Skalnate Pleso 38, 375-384 (2008)

Ap zvezdy vydelyayutsya svoimi sil'nymi magnitnymi polyami i anomaliyami himicheskogo sostava. V obzore dovol'no detal'no (s istoriei) opisyvayutsya issledovaniya etih ob'ektov. Pravda, voprosov ostaetsya bol'shem chem otvetov.


arxiv:0804.1128 Metallichnost' i aktivnost' yuzhnyh zvezd (Metallicities & Activities of Southern Stars)
Authors: J. S. Jenkins, H. R. A. Jones, Y. Pavlenko, D. J. Pinfield, J. R. Barnes, Y. Lyubchik
Comments: 21 pages, 19 figures, 4 tables, accepted A&A (04/04/2008)

Na 2.2-metrovom teleskope v Chili avtory izuchali svoistva 353 yarkih (7.5-9.5)solncepodobnyh zvezd yuzhnogo neba. Opredelyalos' soderzhanie zheleza i hromosfernaya aktivnost'. Interesnyi rezul'tat svyazan s tem, chto neskol'ko zvezd prohodyat stadiyu svoego maunderovskogo minimuma. Sootvetstvenno, mozhno skazat', chto Solnce v techenie svoei zhizni provodit v takom sostoyanii neskol'ko procentov vremeni (poskol'ku dolya zvezd na stadii maunderovskogo minimuma sostavila neskol'ko procentov ot polnoi vyborki).


arxiv:0804.1282 Dvoinye sdB zvezdy s massivnymi kompan'onami (Binary sdB Stars with Massive Compact Companions)
Authors: S. Geier, C. Karl, H. Edelmann, U. Heber, R. Napiwotzki
Comments: 8 pages, 3 figures, Proceedings of the 3rd Meeting on Hot Subdwarf Stars and Related Objects, U. Heber, S. Jeffery, Napiwotzki eds. 2008, ASP Conference Series, 392, 207

Avtory izuchili dvizhenie neskol'kih sdB zvezd, u kotoryh zapodozreny nevidimye kompan'ony. V nekotoryh sluchayah (pravda, v ramkah predpolozhenie o prilivnoi sinhronizacii, kotoroe neploho argumentirovano) udaetsya ogranichit' diapazon uglov naklona orbity, t.e., mozhno opredelyat' massy kompan'onov. Sredi 9 sluchaev pyat' kompan'onov mogut byt' belymi karlikami ili slabymi zvezdami glavnoi posledovatel'nosti. Eto ponyatno. No v chetyreh sluchaya massy poluchayutsya >1 solnechnoi. Znachit, kompan'onami yavlyayutsya massivnye belye karliki ili dazhe neitronnye zvezdy ili chernye dyry. Eto uzhe ne ukladyvaetsya v standartnuyu kartinu. Konechno, mozhet byt' dannye eshe budut peresmotreny, tem ne menee rezul'tat interesnyi.


miniobzor arxiv:0804.1527 O-zvezdy ponizhennoi svetimosti: proishozhdenie i evolyucionnye svyazi (Subluminous O Stars - Origin and Evolutionary Links)
Authors: Uli Heber
Comments: 11 pages, to appear in "Hydrogen deficient stars", K. Werner & T. Rauch (eds.), ASP Conference Series, Vol. 391, p.245 (2008)

Na vysokih galakticheskih shirotah nablyudayutsya slabye golubye zvezdy. V obzore rech' idet o zvezdah spektral'nogo klassa O, no men'shei svetimosti, chem obychnye zvezdy etogo klassa. Eto, t.o., goryachii analog sdB zvezd. Poslednie chasto nablyudayut v tesnyh dvoinyh sistemah. Ih interpretiruyut kak zvezdy gorizontal'noi vetvi (t.e. tam idet gorenie geliya), no s ochen' nebol'shimi vodorodnymi obolochkami (t.e. vodorod v obolochke ne gorit). Ih eshe nazyvayut ekstremal'nymi zvezdami gorizontal'noi vetvi. Oni neposredstvenno prevratyatsya v belye karliki, minuya asimptoticheskuyu vetv'. Eti zvezdy - sdB - po svoim spektral'nym svoistvam pohozhi drug na druga. V to vremya kak slabye O-zvezdy bolee neodnorodny v etom smysle. V chastnosti, est' zvezdy etogo tipa s bol'shim so znachitel'nymi sledami geliya v spektrah, i zvezdy bez nih.

Kakovo proishozhdenie sdO zvezd, t.e. kakov ih evolyucionnyi status? Okonchatel'nogo otveta net. Obsuzhdaetsya neskol'ko variantov. Sredi nih pozdnyaya vspyshka zvezdy (eto gelievaya vspyshka v yadre), uzhe ushedshei s vetvi krasnyh gigantov v storonu belyh karlikov. A takzhe - sliyanie dvuh belyh karlikov.

V zaklyuchenie, v stat'e opisyvaetsya otkrytie sdO zvezdy s ochen' bol'shoi prostranstvennoi skorost'yu (700 km v sek). Polagayut, chto zvezdy ``razgonyayutsya'' za schet vzaimodeistviya so sverhmassivnoi chernoi dyroi v centre Galaktiki. Esli eto tak, to mozhno opredelit', kogda zvezda byla vybroshena iz centra. V sluchae obsuzhdaemoi sdO zvezdy eto 36 millionov let nazad.

Sm. takzhe stat'yu arxiv:0804.2366, gde tozhe rech' idet ob O-zvezdah, bednyh vodorodom i imeyushih ponizhennuyu svetimost', hotya eto i ne sdO-zvezdy (sm. risunok 1, gde pokazano polozhenie raznyh tipov proevolyucionirovavshih goryachih zvezd na diagramme temperatura-uskorenie).


arxiv:0804.2553 Akkuratnye rasstoyaniya do blizkih massivnyh zvezd s uchetom novoi obrabotki syryh dannyh Hipparcos (Accurate distances to nearby massive stars with the new reduction of the Hipparcos raw data)
Authors: J. Maiz Apellaniz, E. J. Alfaro, A. Sota
Comments: 6 pages, Poster presented at IAU Symposium 250: Massive stars as cosmic engines, 10-14 December 2007.

Avtory provodyat pereocenku rasstoyanii do nekotoryh blizkih massivnyh zvezd (sredi kotoryh, konechno, mnogo yarkih izvestnyh ob'ektov). Rezul'taty prosto porazitel'nye (chto, razumeetsya, vyzyvaet zdorovyi skepticizm). Naprimer, rasstoyanie do Deneba ocenivali v 13.26 kpk (pravda, s ochen' bol'shoi oshibkoi), a teper' ono stalo 0.48 kpk.


Vypusk 182. 18-31 marta 2008

arxiv:0803.2691 Otkrytie dvuh magnitnyh massivnyh zvezd v skoplenii Tumannosti Oriona: klyuch k proishozhdeniyu magnitnyh polei neitronnyh zvezd? (Discovery of two magnetic massive stars in the Orion Nebula Cluster: a clue to the origin of neutron star magnetic fields?)
Authors: V. Petit, G.A. Wade, L. Drissen, T. Montmerle, E. Alecian
Comments: 6 pages, Accepted by MNRAS

Kak izvestno, proishozhdenie magnitnyh polei neitronnyh zvezd, osobenno magnitarov, ostaetsya tainoi. To li pole generiruetsya na stadii protoneitronnoi zvezdy, to li yadro zvezdy-praroditelya imelo sil'noe pole, kotoroe posle kollapsa yadra stalo polem neitronnoi zvezdy. U obeih gipotez est' svoi problemy. Odnoi iz problem gipotezy o reliktovom pole yavlyaetsya maloe kolichestvo izvestnyh magnitnyh massivnyh zvezd.

V stat'e avtory raportuyut ob otkrytii dvuh massivnyh zvezd s polyami poryadka kilogaussa.

Na moi vzglyad, mozhet vozniknut' odna problema. Delo v tom, chto vse izvestnye magnitary - odinochnye. Hotya nikakoi selekcii v pol'zu etogo net. Mezhdu tem, iz treh magnitnyh massivnyh zvezd dve vhodyat v kratnye sistemy. Konechno, daleko ne vse dvoinye perezhivut vzruv sverhnovoi. Tem ne menee, imeya uzhe bolee 10 kandidatov v magnitary, stoit zadumat'sya nad ih odinochnost'yu.


arxiv:0803.3161 Nukleosintez i evolyuciya massivnyh zvezd bez metallov (Nucleosynthesis and Evolution of Massive Metal-Free Stars)
Authors: Alexander Heger, S. E. Woosley
Comments: 54 pages, 15 figures, submitted to ApJ

Avtory izuchayut evolyuciyu i vzryvy massivnyh (10-100 solnechnyh mass) zvezd kraine maloi metallichnosti, tochnee, sovsem bez tyazhelyh elementov. Modeliruyutsya krivye bleska i massy ostatkov. Vse eto kraine vazhno dlya ponimaniya togo, kak zhili i umirali samye pervye zvezdy. Osobenno sushestvenno ponyat', kak protekal nukleosintez, t.k. imenno eti zvezdy pervymi obogatili mezhzvezdnuyu sredu tyazhelymi elementami (populyarnoe vvedenie v nukleosintez sm., naprimer, v aprel'skom nomere Vokrug Sveta za 2008 god).

Zvezdy bez metallov ili s kraine malym ih soderzhaniem chashe porozhdayut v konce svoei evolyucii chernye dyry, i v srednem kompaktnye ostatki takih zvezd massivnee. Raspredelenie obiliya elementov, voznikayushee posle cikla nukleosinteza, hotya vcelom i napominaet solnechnoe, no imeet ryad osobennostei. Dlya elementov legche kremniya podavlen sintez yader s nechetnym zaryadom, a takzhe izotopov, bogatyh neitronami. Krome togo, malo elementov tyazhelee germaniya. Evolyuciya zvezd dazhe s kraine malym nachal'nym soderzhaniem tyazhelyh elementov otlichaetsya ot toi, chto rassmotrena v dannoi stat'e. Tekst stat'i - tol'ko pervye 11 stranic. Dalee tablicy i risunki.


obzor arxiv:0803.3527 Tekushee sostoyanie astroseismologii (The Current Status of Asteroseismology)
Authors: C. Aerts, J. Christensen-Dalsgaard, M. Cunha, D.W.Kurtz
Comments: 20 pages, 5 figures, accepted for publication in Solar Physics

Avtory rassmatrivayut osnovnye podhody i rezul'taty v astroseismologii. V nachale rassmotreny zvezdy tipa Solnca, zatem avtory obsuzhdayut vozmozhnost' opredeleniya parametrov konvektivnyh oblastei v nedrah zvezd metodami astroseismologii. Posle etogo pokazano, kak mozhno ocenivat' profil' vnutrennego vrasheniya zvezd raznyh tipov (vklyuchaya belye karliki). Nakonec v zaklyuchenie avtory perehodyat k obsuzhdeniyu nereshennyh voprosov, otvety na kotorye mozhno budet poluchit' v otnositel'no nedalekom budushem.


arxiv:0803.3596 Vyhod udarnoi volny sverhnovoi iz krasnogo sverhgiganta (Supernova Shock Breakout from a Red Supergiant)
Authors: Kevin Schawinski et al.
Comments: 19 pages, 6 figures

Nedavno ya rasskazyval o rabote 0802.1712, v kotoroi avtory pronablyudali rentgenovskuyu vspyshku s posleduyushei vspyshkoi v UF. Avtorskaya interpretaciya: vyhod udarnoi volny sverhnovoi iz plotnogo vetra kompaktnogo praroditelya. I vot novyi rezul'tat.

Zdes' avtory predstavlyayut rezul'taty nablyudenii togo, chto, po vsei vidimosti yavlyaetsya vyhodom udarnoi volny iz krasnogo sverhgiganta. Etot rezul'tat s bol'shei dostovernost'yu mozhno svyazat' s vyhodom udarnoi volny, chem rentgenovskii rezul'tat Soderberg et al. (2008). Vidno poyarchenie sverhgiganta do vyhoda udarnoi volny. Sobstvenno, nablyudaetsya ne sam vyhod volny, a progrev poverhnosti prekursorom udarnoi volny, hotya etot effekt inogda nazyvayut "vyhodom" (avtory obsuzhdayut etot terminologicheskii vopros v pervom abzace na vtoroi stranice).

Avtoram pomogla pravil'naya metodika nablyudenii. V 2004 godu odnovremenno s obzorom po poisku sverhnovyh (SNLS) tu zhe oblast' neba nablyudali na UF kosmicheskom teleskope GALEX. Odno iz sobytii (SNLS-04D2dc), klassificirovannoe kak sverhnovaya vtorogo tipa, pokazalo v dannyh GALEX uyarchenie za dve nedeli do opticheskoi vspyshki.

Galaktika, v kotoroi nablyudalas' sverhnovaya - normal'naya spiral' s sil'nym zvezdoobrazovaniem na z=0.1854. Polucheny detal'nye spektry samoi sverhnovoi, a takzhe spektry galaktiki. Galaktika takzhe nablyudalas' na Habble.

Avtory govoryat o sverhgigante na osnove krivoi bleska sverhnovoi. V nei nablyudaetsya plato, kotoroi svyazyvayut s tem, chto vzorvalas' bol'shaya (protyazhennaya) zvezda.

Sushestvenno, chto dannye po poyarcheniyu do vspyshki mozhno sravnivat' s teoreticheskimi modelyami vzryva. Analiz poyarcheniya (ono prodalzhalos' okolo 6 chasov) podtverzhdaet, chto vzorvalsya sverhgigant s radiusom 500-1000 solnechnyh.

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.


arxiv:0803.3836 Raznica temperatur v polose nestabil'nosti cefeid trebuet razlichii v naklone i nul'-punkte zavisimosti period-svetimost' (Temperature Differences in the Cepheid Instability Strip Require Differences in the Period-Luminosity Relation in Slope and Zero Point)
Authors: Allan Sandage, G. A. Tammann
Comments: 15 pages, 1 table, 4 figures, submitted to The ApJ

Avtory eshe raz vozvrashayutsya k voprosu zavisimosti naklona i nul'-punkta zavisimosti period-svetimost' dlya cefeid ot metallichnosti. Avtory pokazyvayut, chto dlya raznyh galaktik (raznaya metallichnost') polosa nestabil'nosti na diagramme Gercshprunga-Ressela budet sdvinutoi. Sledstviem etogo i yavlyaetsya raznaya zavisimost' period-svetimost'. Razumeetsya, eto mozhet skazat'sya na ocenke kosmologicheskih rasstoyanii (effekt poryadka 15 procentov).


Vypusk 181. 01-17 marta 2008 goda

arxiv:0803.0005 Dolya dvoinyh v sharovom skoplenii NGC 6397 (The binary fraction in the globular cluster NGC 6397)
Authors: D.S. Davis et al.
Comments: 19 pages, 7 figures, accepted in AJ

Dlya dinamicheskoi evolyucii sharovyh skoplenii ochen' vazhna nachal'naya dolya dvoinyh zvezd. Eta velichina izvestna kraine ploho. Zato chislennye raschety pokazyvayut, chto eta dolya malo izmenyaetsya na bol'shih rasstoyaniyah ot centra skopleniya (za radiusom, soderzhashim polovinu massy). Avtory ispol'zuyut nablyudeniya na Kosmicheskom teleskope dlya opredeleniya etoi velichiny. Poluchaetsya, chto nachal'naya dolya dvoinyh v sharovyh skopleniyah sostavlyaet vsego lish' okolo 1 procenta!


miniobzor arxiv:0803.1170 Poterya massy krasnymi gigantami (Mass-loss from Red Giants)
Authors: Brian Espey, Cian Crowley
Comments: 11 pages, Revised version of review submitted to the RS Oph meeting, Keele 2007

Nebol'shoi obzor po vetru ot krasnyh gigantov. Podrazumevayutsya zvezdy do asimptoticheskoi vetvi. Avtory podrazdelyayut vetra na tri kategorii: veter ot goryachih OV-zvezd, koronal'nyi veter ot holodnyh zvezd glavnoi posledovatel'nosti i gigantov rannego F i pozdnego K klassov, i, nakonec, veter ot holodnyh gigantov, kotoryi i yavlyaetsya predmetom stat'i. Avtory ukazyvayut, chto v etoi oblasti est' eshe mnogo neponyatnogo.


arxiv:0803.1638 Nablyudeniya pul'siruyushego belogo karlika EC 20058-5234 s goryachei gelievoi atmosferoi s pomosh'yu Vsemirnogo Teleskopa (Whole Earth Telescope observations of the hot helium atmosphere pulsating white dwarf EC 20058-5234)
Authors: WET Collaboration
Comments: 19 pages, 8 figures, 5 tables, MNRAS accepted

V etoi stat'e menya privlekla organizaciya nablyudenii. Whole Earth Telescope - eto kollaboraciya, stavyashaya svoei zadachei provedenie nepreryvnogo monitoringa ob'ektov na neskol'kih nebol'shih (1-2 metra) nezavisimyh teleskopah, raskidannyh po dolgote.

V dannoi rabote rasskazyvaetsya o monitoringe pul'sacii odnogo iz belyh karlikov. Bylo ispol'zovano chetyre teleskopa (Novaya Zelandiya, Yuzhnaya Afrika, Braziliya, Chili). Na risunke pokazana statitstika nablyudenii. Vidno, chto v techenie primerno chetyreh dnei udalos' obespechit' 90-procentnoe nablyudenie (meshala pogoda).


Pokazany momenty provedeniya nablyudeniina kazhdom iz chetyreh teleskopov.

Nepreryvnye nablyudeniya chasto byvayut neobhodimy. Horosho, chto inogda ih taki udaetsya provodit'.


obzor arxiv:0803.1833 Plotnye zvezdnye populyacii: nachal'nye usloviya (Dense Stellar Populations: Initial Conditions)
Authors: Pavel Kroupa
Comments: 85 pages. To appear in The Cambridge N-body Lectures, Sverre Aarseth, Christopher Tout, Rosemary Mardling (eds), Lecture Notes in Physics Series, Springer Verlag

Zamechatel'nyi obzor po svoistvam zvezd v plotnyh skopleniyah. Vse eti dannye neobhodimy dlya zadaniya nachal'nyh uslovii pri modelirovanii dinamiki skoplenii - otsyuda i vtoraya chast' zagolovka.


Vypusk 180. 14-29 fevralya 2008 goda

miniobzor arxiv:0802.1924 Zvezdy maloi metallichnosti (Metal-Poor Stars)
Authors: Anna Frebel
Comments: 16 pages, invited review talk, to appear in the ASP conference proceedings of the "Frank N. Bash Symposium 2007: New Horizons in Astronomy", editors: A. Frebel, J. Maund, J. Shen, M. Siegel

Nebol'shoi obzor po malometallichnym zvezdam v nashei Galatike. Krome svodki dannyh i rassuzhdenii o nereshennyh voprosah, avtor kratko opisyvaet istoriyu otkrytiya takih ob'ektov.


miniobzor arxiv:0802.2805 Dostizheniya v fizike massivnyh zvezd (Developments in physics of massive stars)
Authors: Georges Meynet et al.
Comments: 13 pages, 10 figures, IAU Symp. 250, Massive stars as Cosmic Engines, F. Bresolin, P.A. Crowther, J. Puls Eds

Kak obychno: idet potok novyh dannyh i razvivayutsya modeli opisaniya fiziki. Na etot raz i to, i drugoe otnositsya k massivnym zvezdam.

Posle spiska novyh nablyudatel'nyh obzorov i perechnya poluchennyh rezul'tatov avtory perehodyat k opisaniyu novyh modelei, uchityvayushih vrashenie zvezd, i k sravneniyu rezul'tatov raschetov s nablyudeniyami. Osnovnoi vyvod, pri opisanii massivnyh zvezd bez ucheta vrasheniya ne oboitis'!


arxiv:0802.4078 Obnaruzhenie magnitnyh polei u ochen' molodyh massivnyh zvezd W601 (NGC 6611) i OI 201 (NGC 2244) (Discovery of magnetic fields in the very young, massive stars W601 (NGC 6611) and OI 201 (NGC 2244))
Authors: E. Alecian et al.
Comments: 5 pages, Accepted for publication as a letter in A&A

Izvestno, chto mnogie (tochnee okolo 5 procentov) A/V-zvezdy imeyut dostatochno sil'nye magnitnye polya. Proishozhdenie etih polei ostaetsya do konca neizvestnym. To li eto ostatochnye polya, kotorye byli eshe v molekulyarnom oblake, iz kotorogo formirovalas' zvezda. To li polya usilivalis' v processe formirovaniya i evolyucii zvezdy. Dlya vyyasneniya okonchatel'nogo otveta vazhno izmeryat' polya u molodyh zvezd do stadii glavnoi posledovatel'nosti. V rabote predstavleny rezul'taty po dvum takim ob'ektam. Sil'nye polya obnaruzheny, i pri etom zvezdy otnositel'no medlenno vrashayutsya (period v neskol'ko dnei protiv periodov menee dnya i analogichnyh zvezd bez sil'nyh polei). Vse eto yavlyaetsya argumentom v pol'zu togo, chto polya ostatochnye.


Vypusk 179. 01-14 fevralya 2008 goda

miniobzor arxiv:0802.0046 Rentgenovskoe izluchenie O-zvezd (X-ray emission from O stars)
Authors: David H. Cohen
Comments: 9 pages; color figures. To appear in IAU Symposium 250, "Massive Stars as Cosmic Engines," Kauai, HI, December 2007; eds. Bresolin, Crowther, & Puls, Cambridge University Press, 2008.

Na raznyh stadiyah svoei zhizni massivnye O-zvezdy yavlyayutsya istochnikami rentgenovskogo izlucheniya, no prichiny dlya nego razlichny. Avtor na primere nablyudaemyh ob'ektov rassmatrivaet mehanizmy, privodyashie k rentgenovskomu izlucheniyu massivnyh zvezd, i obsuzhdaet ego svoistva. Krome togo, rentgenovskie dannye ispol'zuyutsya dlya ocenki tempa poteri massy zvezdoi. Avtor polagaet, chto standartnye ocenki poter' zavysheny.


arxiv:0802.0096 Poisk vnesolnechnyh planet v universitete Novogo Uelsa: katalog peremennyh zvezd v polyah, nablyudavshihsya v 2004-2007 gg. (The University of New South Wales Extrasolar Planet Search: a catalogue of variable stars from fields observed 2004--2007)
Authors: J.L. Christiansen et al.
Comments: 14 pages, 8 figures, 6 tables, accepted for publication in MNRAS

Kak eto chasto byvaet, pri obshirnyh poiskovyh rabotah poluchaetsya mnogo pobochnyh rezul'tatov. Vot i v programme poiska ekzoplanet, osushestvlyavsheisya uchenymi universiteta Novogo Uelsa (Avstraliya), est' takoi "pobochnyi produkt" - dannye po peremennym zvezdam.

Avtory predstavlyayut katalog iz 850 peremennyh zvezd, 659 iz kotoryh otsutstvuyut v OKPZ, a takzhe v katalogah zvezd, zapodozrennyh v peremennosti.


miniobzor arxiv:0802.0207 Pervye zvezdy (The First Stars)
Authors: Jarrett L. Johnson, Thomas H. Greif, Volker Bromm
Comments: 12 pages, 9 figures, proceedings of the IAU Symposium 250 "Massive stars as cosmic engines"

Neplohoi obzor po prakticheski vsem aspektam, svyazannym s poyavleniem, proyavleniyami pervyh zvezd, a takzhe s ih vkladom v himicheskuyu evolyuciyu. Esli ne interesuyut detali, a vazhno uznat' obshuyu kartinu, to etu stat'yu mozhno smelo rekomendovat'.


arxiv:0802.0456 Obzor v poiskah "nichto": monitoring milliona sverhgigantov dlya obnaruzheniya neudavshihsya sverhnovyh (A Survey About Nothing: Monitoring a Million Supergiants for Failed Supernovae)
Authors: C.S. Kochanek et al.
Comments: 6 pages, 3 figures, submitted to ApJ

Teoretiki predskazyvayut, chto est' tip kollapsa, ne soprovozhdayushiisya yarkoi vspyshkoi. Takie sobytiya nazyvayut "neudavshimisya sverhnovymi". Byla zvezda - i vdrug BAC! - pustoe mesto (konechno, ostaetsya kompaktnyi ob'ekt, no ego s bol'shogo rasstoyaniya my ne vidim.

V stat'e predlagaetsya krasiveishaya ideya. Iskat' takie sobytiya, provodya monitoring bol'shogo kolichestva yarkih sverhgigantov v blizkih galaktikah. Ocenki pokazyvayut, chto raz v god mozhno nadeyat'sya (esli byt' optimistom), chto odin iz nih "ischeznet".

Obsudit' v ZhZh-soobshestve ru_astroph
Obsudit' na Astroforume v Nauchnoi panorame.


Vypusk 178. 22-31 yanvarya 2008 goda

miniobzor arxiv:0801.3175 Mnozhestvennye zvezdnye populyacii v galakticheskih sharovyh skopleniyah: nablyudatel'nye ukazaniya (Multiple Stellar Populations in Galactic GCs: Observational Evidence)
Authors: Giampaolo Piotto
Comments: 10 pages, Invited talk given at the Cefalu' 2007 Workshop "XXI Century Challenges for Stellar Evolution". To appear in Memorie della Societa' Astronomica Italiana, vol. 79/2, eds. S. Cassisi & M. Salaris

Obychno schitaetsya, chto standartnoe, "horoshee" sharovoe skoplenie sostoit iz zvezd odnogo vozrasta i himicheskogo sostava. Odnako poslednie detal'nye fotometricheskii issledovaniya pokazyvayut nekotoroe raznoobrazie svoistv skoplenii. Vozmozhno, chto eto svyazano s tem, chto chast' skoplenii (kak, naprimer, Omega Centavra i M54 - dva iz shesti skoplenii, u kotoryh obnaruzheno raznoobrazie sostava) yavlyaetsya ostatkami karlikovyh galaktik, zahvachennyh nashei. Krome togo, massivnye sharovye skopleniya (chetyre drugih skopleniya - NGC 6388, NGC 1851, NGC 6441 i NGC 2808, takzhe kak i Omega Centavra i M54, yavlyayutsya massivnymi - massa bolee milliona solnechnyh), kak polagayut nekotorye avtory, mozhet zahvatyvat' zvezdy vo vremya svoego formirovaniya.


arxiv:0801.3778 Sistematicheskie otkloneniya pri opredelenii nachal'noi funkcii mass iz-za razmera binov i nerazreshennyh sistem (IMF biases created by binning and unresolved systems)
Authors: J. Maiz Apellniz
Comments: : 6 pages, 10 figures, to appear in "Young massive clusters, initial conditions and environments"

Nebol'shoe izlozhenie dvuh bol'shih rabot. Avtor analiziruet, chto meshaet tochnomu opredeleniyu funkcii mass. Pristal'no rassmotreny dva momenta: razmer binov (po masse) i rol' kratnyh zvezd (kak fizicheskih, tak i opticheskih). Tam gde chto-to mozhno ispravit', avtor predlagaet puti korrekcii opredelennoi funkcii mass. V nekotoryh sluchayah (naprimer, kogda na izobrazhenii "slipaetsya" bol'shoe chislo zvezd) nichego sdelat' uzhe nel'zya.


Vypusk 177. 10-21 yanvarya 2008 goda

miniobzor arxiv:0801.1777 Nukleosintez v zvezdnyh vspyshkah (Nucleosynthesis in stellar flares)
Authors: V. Tatischeff, J.-P. Thibaud, I. Ribas
Comments: 12 pages, 3 figures, contribution to the Proceedings of the XIXemes Rencontres de Blois, Matter and energy in the Universe, Blois, France, May 2007

Litii obrazuetsya v hode pervichnogo nukleosinteza v molodoi vselennoi. V zvezdah litii ne proizvoditsya v cepochkah temroyadernyh reakcii, za schet kotoryh zvezdy svetyat. Poetomu v osnovnom ves' litii vo vselennoi pervichnyi. Odnako, est' interesnaya hitrost'.

Vo vspyshkah na zvezdah mozhet obrazovyvat'sya nemnozhko litiya, sovsem chut'-chut'. V masshtabah vselennoi eto kraine malyi vklad. Odnako soderzhanie litiya zachastuyu opredelyaetsya imenno po nablyudeniyam zvezd. Poetomu dazhe nebol'shaya dobavka litiya vo vneshnih sloyah zvezdy mozhet vvesti issledovatelya v zabluzhdenie, t.k. on mozhet zakrichat' "Evrika!", ne vyliv sebe na golovu vedro holodnoi vody reshit', chto on nashel argument v pol'zu vysokogo soderzhaniya litiya vo vselennoi vcelom (ili v pol'zu togo, chto litiya bylo mnogo lokal'no v tom gazovom oblake, iz kotorogo formirovalas' nablyudaemaya zvezda).

Avtory detal'no razbirayut vozmozhnoe uvelicheniya soderzhaniya litiya v poverhnostnyh sloyah zvezd za schet generacii etogo elementa v rezul'tate vspyshek. Kstati, naibolee interesny (s kosmologicheskoi tochki zreniya) nablyudeniya litiya na karlikovyh zvezdah v galo nashei Galaktiki, t.k. malomassivnye zvezdy dolgo zhivut, i, sootvetstvenno, seichas po nim my mozhem uznat' himicheskii sostav na zare formirovaniya nashei zvezdnoi sistemy. Tak vot, kak raz na karlikovyh zvezdah, kak vse pomnyat, vspyshki v osnovnom i proishodyat. Tak chto problema ves'ma aktual'na i ser'ezna.


arxiv:0801.2019 CESAM: svobodnaya programma dlya rascheta zvezdnoi evolyucii (CESAM: a free code for stellar evolution calculations)
Authors: Pierre Morel, Yveline Lebreton
Comments: 13 pages, 1 figure, accepted for publication in Astrophysics & Space Science, ESTA/CoRoT Volume

Podrobno opisyvaetsya paket programm dlya rascheta zvezdnoi evolyucii. Raschety odnomernye. Ne uchityvaetsya vyrozhdenie elektronov.

Navernoe, mnogiem budet interesno takzhe prosmotret' stat'yu arxiv:0801.2022. V nei avtor rassuzhdaet o perspektivah mikrosekundnoi zvezdnoi astrometrii (na takom urovne budet rabotat' sputnik GAIA). Okazyvaetsya, eta zadacha brosaet vyzov i zvezdnym modelyam. Kogda astrometriya vyidet na mikrosekundnyi uroven', odnomernymi modelyami budet uzhe ne oboitis'.


obzor arxiv:0801.2944 Fizika vrasheniya v zvezdnyh modelyah (Physics of rotation in stellar models)
Authors: Georges Meynet
Comments: 32 pages, 7 figures, lectures, CNRS school, will be published by Springer

Ochen' horoshie lekcii, posvyashennye razlichnym fizicheskim processam, svyazannym s vrasheniem zvezd, a takzhe ih vliyaniyu na zvezdnye modeli.


Vypusk 176. 20 dekabrya 2007-09 yanvarya 2008 goda

obzor arxiv:0712.3797 Peremennye zvezdy na nablyudaemoi diagramme G-R (Variable stars across the observational HR diagram)
Authors: Laurent Eyer, Nami Mowlavi
Comments: 21 pages, 9 figures, in Proc. "Helioseismology, Asteroseismology and MHD Connections" (eds. L.Gizon and M. Roth), J. Phys. Conf. Phys. (2008)

Daetsya obzor po pul'siruyushim peremennym zvezdam. Obsuzhdenie idet v kontekste mesta etih zvezd na diagramme Gercshprunga-Ressela, ved' tol'ko v opredelennyh oblastyah nestabil'nosti zvezda nachinaet pul'sirovat'.


arxiv:0712.4149 UF/opticheskaya registraciya kandidatov v prilivnoe razrushenie priborami GALEX i CFHTLS (UV/Optical Detections of Candidate Tidal Disruption Events by GALEX and CFHTLS)
Authors: S. Gezari et al.
Comments: 28 pages, 27 figures, 11 tables, accepted to ApJ

Kak izvestno, proletaya vblizi sveohmassivnoi chernoi dyry v centre galaktiki, zvezdy mogut byt' razrusheny prilivnymi silami. Takoe sobytie budet nablyudat'sya kak dovol'no dlitel'naya vspyshka. Svoistva takih vspyshek proschitany, naideno neskol'ko kandidatov, sledovatel'no, mozhno iskat' novye, pol'zuyas' dostatochno ponyatnoi metodikoi.

V dannoi stat'e avtory predstavlyayut rezul'taty nablyudenii dvuh vspyshek, po vsei vidimosti svyazannyh s prilivnym razrusheniem zvezd chernoi dyroi, v opticheskom i ul'trafioletovom diapazonah.


Vypusk 175. 14-19 dekabrya 2007

arxiv:0712.1871 Vse li massivnye zvezdy rozhdayutsya v OV associaciyah i skopleniyah? (Were All Massive Stars Born in OB Associations and Clusters?)
Authors: You-Hua Chu, Robert A. Gruendl
Comments: 8 pages, 6 figures, Massive Star Formation: Observations Confront Theory, held at Heidelberg on September 10-14, 2007

Postoyanno obsuzhdaetsya vopros o tom, vse li massivnye zvezdy rodilis' v skopleniyah ili associaciyah. Avtory proveli podrobnyi analiz molodyh zvezdnyh ob'ektov v Bol'shom Magellanovom oblake s pomosh'yu kosmicheskogo IK-teleskopa im. Spitcera. Pokazano, chto 65 procentov massivnyh zvezd rozhdaetsya v associaciyah, 85 - v giganstkih molekulyarnyh oblakah (razumeetsya, nichto ne meshaet zvezde vnesti vklad i tuda, i tuda), i lish' okolo 7 procentov - sovsem odinoki. Eto nahoditsya v soglasii s analogichnoi ocenkoi dlya Galaktiki, gde, kak polagayut, 5-10 procentov massivnyh zvezd rozhdayutsya vne skoplenii ili associacii.


miniobzor arxiv:0712.2588 Sovremennye voprosy astroseismologii (Current Issues in Asteroseismology)
Authors: Michael Bazot, Mario J. P. F. G. Monteiro, Christian W. Straka
Comments: 9 pages, 2 figures - to appear in Helioseismology, Asteroseismology and MHD Connections, (Eds) L. Gizon et al., Journal of Physics Conference Series, 2008

Nebol'shoi, no ochen' ponyatnyi obzor po astroseismologii, nachinayushiisya "s azov". Takzhe opisany osnovnye sputniki, postavlyayushie (ili eshe planiruemye) informaciyu dlya astroseismologov.


Vypusk 174. 01-13 dekabrya 2007

miniobzor arxiv:0712.0191 Magnitnye polya massivnyh zvezd (Magnetic fields in massive stars)
Authors: S. Hubrig et al.
Comments: 6 pages, 5 figures, contribution presented at the CP/AP Workshop, Vienna, Austria in September 2007

Opredelenie magnitnyh polei massivnyh zvezd vazhno ne tol'ko samo po sebe, no takzhe i dlya ponimaniya mehanizma vozniknoveniya sil'nyh polei u neitronnyh zvezd - magnitarov (anomal'nyh rentgenovskih pul'sarov i istochnikov myagkih povtoryayushihsya gamma-vspleskov). V korotkoi zametke avtory privodyat vse osnovnye (kstati, dovol'no nemnogochislennye) dannye po izmereniyam polei u OV-zvezd.

O polyah anomal'nyh rentgenovskih pul'sarov sm. arxiv:0712.0009. Avtory stroyat model' izlucheniya etih ob'ektov, i pokazyvayut. Chto polya, opredelennye po spektru, horosho sovpadayut s polyami, ocenennymi po zamedleniyu vrasheniya. Vozniknovenie stol' sil'nyh polei poka ostaetsya neponyatnym. Spruit v nedavnei stat'e eshe raz podcherknul, chto ostatochnye polya massivnyh zvezd ne mogut bez dopolnitel'nogo usileniya ob'yasnit' polya magnitarov....

O polyah A-zvezd arxiv:0712.0173. Avtory issleduyut 13 A-zvezd s cel'yu vyyasnit', mozhet li rentgenovskoe izluchenie etih ob'ektov byt' svyazano s ih magnitnymi polyami. Poluchaetsya, chto ne mozhet.


item arxiv:0712.0247 Scenarii samoobogasheniya sharovyh skoplenii promezhutochnoi metallichnosti (The self-enrichment scenario in intermediate metallicity globular clusters).
Authors: P. Ventura & F. D'Antona
Comments: A&A, 26 pages

Stat'ya yavlyaetsya prodolzheniem serii rabot teh zhe avtorov ob evolyucii zvezd promezhutochnyh mass na stadii asimptoticheskoi vetvi gigantov (AGB stars). Predstavleny rezul'taty chislennogo modelirovaniya evolyucii zvezd v intervale mass 3 < M < 6.3 solnechnyh mass, s pervonachal'nym obiliem geliya Y=0.24 i metallichnost'yu Z=0.001, sootvetstvuyushei [Fe/H]= -1.3 Poluchennye v rezul'tate raschetov teoreticheskie zvezdnye vybrosy (stellar yields) dlya izotopov 12C, 14N, 16O, 19F, 23Na, 25Mg, 26Mg, 27Al sravnivalis' s nablyudaemymi obiliyami v zvezdah sharovyh skoplenii toi zhe metallichnosti. Cel'yu raboty stala proverka gipotezy o vozmozhnosti samoobogasheniya sharovyh skoplenii AGB-zvezdami. Soglasno etoi gipoteze, nablyudaemye v sharovyh skopleniyah himicheskie anomalii i antikorrelyacii obilii O-Na i Mg-Al mozhno ob'yasnit' bystroi evolyuciei pervogo pokoleniya massivnyh AGB-zvezd, obogashayushih mezhzvezdnuyu sredu protoskoplenii tyazhelymi elementami i stimuliruyushih formirovanie vtorogo pokoleniya zvezd, nablyudaemyi himsostav kotoryh otrazhaet sostav obogashennogo gaza. Predskazaniya modeli nahodyatsya v horoshem soglasii s nablyudaemymi obiliyami kisloroda, alyuminiya, ftora i magniya, no ne sposobny ob'yasnit' soderzhaniya natriya i litiya. Po ocenke avtorov, tol'ko samye massivnye AGB-zvezdy s massami 5-6 solnechnyh mass vliyayut na process samoobogasheniya protoskoplenii.


item Obzor arxiv:0712.0828 Formirovanie massivnyh zvezd (The Formation of Massive Stars).
Authors: M.R. Krumholz & I.A.Bonnell
Comments: To be published in Structure Formation in the Universe, 26 pages

Processy rozhdeniya i evolyucii massivnyh zvezd malo izucheny, nesmotrya na sushestvennyi teoreticheskii i nablyudatel'nyi progress v etoi oblasti v poslednie gody. Obzor posvyashen detal'nomu rassmotreniyu dvuh naibolee populyarnyh modelei formirovaniya massivnyh zvezd: modeli vnutrennei akkrecii (core accretion) i poperemennoi akkrecii (competitive accretion). Eti podhody otlichayutsya tem, kogda i kakim obrazom nabiraetsya okonchatel'naya massa budushei zvezdy. Obzor sostoit iz pyati chastei: vvedeniya, opisaniya kazhdoi iz modelei, nereshennyh zadach i budushih nablyudenii.


arxiv:0712.1052 Nazemnye obzory po poisku peremennyh istochnikov v Centavre A: stoit ili net? (Ground-based variability surveys towards Centaurus A: worthwhile or not?)
Authors: Jelte T. A. de Jong, Konrad H. Kuijken, Philippe Heraudeau
Comments: 8 pages, 7 figures, accepted for publication in Astronomy and Astrophysics

Do chego doshel progress! S pomosh'yu skromnyh (2.2 metra) instrumentov lyudi izuchayut peremennye zvezdy v galaktike Centavr A, da eshe nadeyutsya na poiski mikrolinzirovaniya v etoi neblizkoi galaktike! Obnaruzhena 271 peremennaya zvezda. Pokazana effektivnost' metoda nablyudenii.


item Obzor arxiv:0712.1109 Formirovanie massivnyh zvezd: mogushestvo interferometrii (Massive Star Formation: The Power of Interferometry).
Authors: H. Beuther
Comments: Review on the occasion of the Ludwig Biermann prize of the German Astronomical Society, 35 pages

Eshe odin obzor ob evolyucii massivnyh zvezd, osnovnoe vnimanie v kotorom udeleno fizicheskim i himicheskim svoistvam massivnyh zvezd. Obsuzhdaetsya ryad ogranichenii, poluchennyh na osnove submillimetrovoi interferometrii. Detal'no opisany osnovnye koncepcii fiziki i astrohimii massivnyh zvezd, predlozheny nablyudatel'nye testy dlya proverki sushestvuyushih gipotez.


item arxiv:0712.1160 Nukleosintez v rannei vselennoi i konechnye stadii evolyucii zvezd promezhutochnyh mass nulevoi metallichnosti (An Explosive End to Intermediate-Mass Zero-Metallicity Stars and Early Universe Nucleosynthesis).
Authors: H.B. Lau et al.
Comments: MNRAS, 18 pages

Vopros o tom, formiruyutsya li zvezdy promezhutochnyh mass nulevoi (ili predel'no nizkoi) metallichnosti v usloviyah rannei vselennoi, i, esli da, to kakoi vklad oni vnosyat v nukleosintez, ochen' vazhen dlya ponimaniya himicheskoi evolyucii vselennoi. V dannoi rabote predstavleny rezul'taty modelirovaniya massivnyh (5 i 7 mass Solnca) AGB-zvezd nulevoi metallichnosti. Soglasno raschetam avtorov, osobennost' evolyucii massivnyh AGB-zvezd pervichnogo himsostava sostoit v tom, chto v ih central'nyh oblastyah zagoraetsya uglerod, i evolyuciya takih zvezd zakanchivaetsya vzryvom sverhnovyh tipa 1.5, napominayushim vzryv sverhnovyh tipa SN Ia, no s vodorodnoi obolochkoi. Eshe odnoi osobennost'yu evolyucii AGB-zvezd nulevoi metallichnosti yavlyaetsya otsutstvie etapa tret'ego peremeshivaniya (third dredge-up). Vazhnym sledstviem dlya himicheskoi evolyucii yavlyaetsya to, chto elementy s-processa pri etom ne obrazuyutsya, i obogasheniya mezhzvezdnoi sredy imi ne proishodit. Dlya utochneniya nizhnego poroga metallichnosti AGB-zvezd, pri kotorom "vklyuchaetsya" process tret'ego peremeshivaniya, trebuyutsya dal'neishie issledovaniya.


item arxiv:0712.1185 SpectroWeb: sily oscillyatorov absorbcionnyh linii atomov v spektrah Solnca i Prociona (SpectroWeb: oscillator strength measurements of atomic absorption lines in the Sun and Procyon).
Authors: A. Lobel
Comments: To appear in Proc. of the 9th Int. Coll. on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas at Lund, 6 pages

SpectroWeb - special'no razrabotannyi dlya astronomicheskogo soobshestva onlainovyi resurs, kotoryi soderzhit interaktivnyi cifrovoi spektral'nyi atlas yarkih zvezd i dostupen po adresu http://spectra.freeshell.org. Neobhodimost' v edinom standartnom atlase, obnovlyaemom, redaktiruemom i dostupnom vsem zhelayushim, voznikla v svyazi s bystrym progressom v oblasti zvezdnoi spektroskopii. V nastoyashii moment SpectroWeb soderzhit spektry vysokogo razresheniya shesti yarkih zvezd: Betelgeuse (alpha Ori; M2 Iab), Arcturus (alpha Boo; K1 III), The Sun (G2 V), beta Aqr (G0 Ib), Procyon (alpha CMi A; F5 IV-V) i Canopus (alpha Car; F0 II). Effektivnye temperatury etih zvezd otlichayutsya v srednem na 1000 K i sootvetstvuyut intervalu zvezdnyh temperatur ot 3500 K (M) do 7500 K (F). Dannaya publikaciya soderzhit informaciyu o vnesennyh v atlas SpectroWeb dopolneniyah. Dobavleny sily lineinyh oscillyatorov log(gf) dlya 1178 absorbcionnyh linii v spektre Solnca i sily lineinyh oscillyatorov log(gf) dlya 660 linii v spektre Prociona.


Vypusk 173. 20-30 noyabrya 2007

arxiv:0711.2685 Zvezdoobrazovanie v peremychke neitral'nogo vodoroda mezhdu M81 i M82 (Star-formation in the HI bridge between M81 and M82)
Authors: Duilia F. de Mello et al.
Comments: 22 pages, Astronomical Journal accepted

Avtory issleduyut zvezdnyi sostav v peremychke, soedinyayushem galaktiki M81 i M82 (t.n Petlya Arpa). Interesno, chto tam obnaruzheno kak ochen' molodoe, tak i ochen' staroe naselenie. Avtory polagayut, chto molodoee obrazovalos' neposredstvenno v peremychke, a staroe bylo vybrosheno iz galaktik 200-300 millionov let nazad, kogda oni aktivno vzaimodeistvovali drug s drugom prilivnym obrazom.


item arxiv:0711.2761 Mul'timodal'nye gorizontal'nye vetvi: empiricheskoe podtverzhdenie i vozmozhnye evolyucionnye scenarii (Multimodal Horizontal Branches: Empirical Evidence and Possible Evolutionary Scenarios).
Authors: M. Catelan
Comments: Mem. SAI, 12 pages

Nesmotrya na mnogoletnie issledovaniya, sverhmassivnye sharovye skopleniya (takie kak Omega Centavra) neizmenno soderzhat v sebe bol'she zagadok, chem otvetov. Za poslednee desyatiletie statistika nablyudatel'nyh dannyh po sharovym skopleniyam znachitel'no uluchshilas'. Stalo ponyatno, chto nablyudavshiesya na CMD "provaly" byli skoree vsego vyzvany selekcionnymi effektami. Vozrosla uverennost' v tom, chto mul'timodal'nye gorizontal'nye vetvi v massivnyh skopleniyah deistvitel'no sushestvuyut. Po krainei mere, v neskol'kih skopleniyah sushestvovanie dvuh i bolee mod gorizontal'noi vetvi bylo podtverzhdeno i dokazano. V kachestve primera mozhno privesti NGC 2808 - horosho izuchennoe skoplenie takogo roda. Mul'timodal'nost' mozhet byt' vyzvana mnogimi faktorami. Teoreticheskaya interpretaciya etogo yavleniya do sih por otsutsvuet. Dlya otveta na etot vopros trebuyutsya masshtabnye nablyudatel'nye programmy i teoreticheskoe issledovanie slozhnyh fizicheskih processov, proishodyashih na rannih etapah evolyucii sverhmassivnyh sharovyh skoplenii. Detal'noe obsuzhdenie etoi temy soderzhitsya v stat'e.


arxiv:0711.2932 Baza dannyh po galakticheskim sharovym skopleniyam (Galactic Globular Clusters Database: a progress report)
Authors: M. Castellani
Comments: 3 pages, proceedings of "XXI Century challenges for stellar evolution" (Cefalu', Italy), eds. S. Cassisi and M. Salaris, to be published in MemSAIt, 79, 2.

Kratko opisyvaetsya baza dannyh po sharovym skopleniyam. Sama baza dostupna tut http://www.mporzio.astro.it/~marco/gc/.

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.


istoricheskii obzor arxiv:0711.3139 Yadernaya astrofizika do 1957 (Nuclear Astrophysics Before 1957)
Authors: Edwin E. Salpeter
Comments: 16 pages

Voshititel'naya yasnaya stat'ya, v kotoroi avtor vspominaet klyuchevye sobytiya rannei istorii yadernoi astrofiziki, v kotoryh on prinimal uchastie, a takzhe delaet interesneishie otstupleniya, posvyashennye otdel'nym lichnostyam ili aktual'nym sovremennym voprosam.

Pochemu "do 1957"? Potomu chto v tom godu vyshla stat'ya, izvestnaya kak B2FH (Burbidge, Burbidge, Fowler, Hoyle). No v stat'e Salpitera rech' idet o sobytiya, kotorye predshestvovali poyavleniyu etoi raboty.

Pereskazyvat' bespolezno-chitaite.

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.


arxiv:0711.3227 Redkie belye karliki s uglerodnymi atmosferami (Rare White dwarf stars with carbon atmospheres)
Authors: P. Dufour, James Liebert, G. Fontaine, N. Behara
Comments: 7 pages, 1 figure, to appear in Nov 22nd 2007 edition of Nature

Obychno belye karliki imeyut vodorodnuyu ili gelievuyu atmosferu. A tut vdrug - uglerodnaya. Eto ne vpisyvaetsya v standartnye scenarii evolyucii.

Sm. takzhe arxiv:0711.3458


miniobzor arxiv:0711.4047 Obratnaya svyaz' (v obrazovanii massivnyh zvezd): teoreticheskii obzor (Feedback Processes [in Massive Star Formation]: A Theoretical Perspective)
Authors: Mordecai-Mark Mac Low (
Comments: for publication in the proceedings of "Massive Star Formation: Observations Confront Thoery", ASP conference series, eds. H. Beuther et al., 10 pages

Esli vy hotite uznat', kak mnogo my eshe ne ponimaem v voprose formirovaniya massivnyh zvezd, i skol' veliko kolichestvo obsuzhdaemyh interesnyh idei, to vam syuda.

Avtor daet obzor po sleduyushei probleme: chto opredelyaet maksimal'nuyu massu zvezd. Po vsei vidimosti, verhnii predel na massu zvezd v kazhdom konkretnom sluchae opredelyaetsya summarnym deistviem mnogih faktorov, kotorye vse svyazany s "obratnoi svyaz'yu". T.e., chem massivnee obrazuyushayasya zvezda, tem bol'she ona izluchaet, tem sil'nee veter i istecheniya, chto, v svoyu ochered', prepyatstvuet dal'neishemu uvelicheniyu massy.

Obsudiv mnozhestvo mehanizmov (zamechu, chto v osnovnom ssylki na raboty 2006-2007 goda, t.o., vse "s pylu s zharu"), avtor rezyumiruet, chto my vse-taki poka ne ponimaem, chto opredelyaet maksimal'nuyu massu zvezdy.

Sm. takzhe obzor po obrazovaniyu massivnyh zvezd arxiv:0711.4912.


arxiv:0711.4250 Periodichnost' aktivnosti Eta Kilya (The periodicity of the eta Carinae events)
Authors: A. Damineli et al.
Comments: 9 pages, 4 EPS figures, submitted to MNRAS

Avtory analiziruyut povedenie izvestnoi massivnoi zvezdy Eta Kilya. Podozrevayut, chto eto dvoinaya sistema. I v samom dele, avtory pokazyvayut, chto dannye soglasuyutsya s ochen' dlinnym periodom poryadka 2023 dnya.

Sm. takzhe arxiv:0711.4297


item arxiv:0711.4310 Zvezdnaya evolyuciya v real'nom vremeni: variacii periodov RR Liry Galaktiki (Stellar evolution in real time: Period variations in galactic RR Lyr stars).
Authors: E. Poretti et al.
Comments: MemSAI, 5 pages

Associaciya lyubitelei astronomii i professional'nyh astronomov GEOS postavila pered soboi zadachu sobrat' dostupnye dannye po vsem zvezdam RR Liry, nablyudeniya o kotoryh upominalis' v nauchnoi literature za poslednie sto let. V nastoyashee vremya sozdannyi associaciei katalog soderzhit informaciyu o bolee chem 3000 zvezd i dostupen vsem zhelayushim po adresu http://dbrr.ast.obs-mip.fr/. Hotya informaciya o krivyh yarkosti zvezd RR Liry sobrana avtorami iz samyh raznyh istochnikov (kak na osnove CCD, tak i vizual'nyh, fotograficheskih, fotoelektricheskih nablyudenii), bol'shoi vremennoi interval nablyudenii pozvolil dovol'no chetko prosledit' variacii perioda zvezd. Naidennye tendencii uvelicheniya i umen'sheniya periodov yavno svidetel'stvuyut ob evolyucionnyh effektah. Dal'neishii progress proekta "Zvezdnaya evolyuciya v real'nom vremeni" trebuet informacii o gorazdo bol'shem kolichestve zvezd. Teleskopy-roboty TAROTs, ispol'zuemye seichas dlya monitoringa zvezd RR Liry yarche trinadcatoi zvezdnoi velichiny, chastichno reshayut etu problemu.


Vypusk 172. 01-19 noyabrya 2007

arxiv:0711.1617 Zatmennye dvoinye sistemy v Bol'shom i Malom Magellanovyh oblakah po dannym proekta MACHO: vyborka (Eclipsing binary stars in the Large and Small Magellanic Clouds from the MACHO project: The Sample)
Authors: Lorenzo Faccioli et al.
Comments: 67 pages, 40 figures, AJ, 2007, 134, 1963

Kak izvestno, soglasno teorii zagovora obzory po mikrolinzirovaniyu byli sdelany, chtoby poluchit' dannye po peremennym zvezdam, poskol'ku inache na nih ne dali by deneg. Eto, konechno, shutka, no v kazhdoi shutke est' dolya yumora. V samom dele, imenno blagodarya proektam po mikrolinzirovaniyu my imeem kolossal'nyi nabor dannyh po peremennym zvezdam raznyh tipov. V dannoi stat'e predstavleny dannye po neskol'kim tysyacham zatmennyh dvoinyh v Magellanovyh oblakah. Analiz chasti dannyh mozhno naiti zdes'.


diskussiya arxiv:0711.1752 Diskussiya: zvezdoobrazovanie v galaktikah, chto delaem dal'she? (Panel discussion I: Star formation in galaxies: how do we continue?)
Authors: Johan H. Knapen
Comments: 7 pages, Written account of conference panel discussion, to be published in proc. Pathways through an Eclectic Universe, Eds. J. H. Knapen, T. J. Mahoney, & A. Vazdekis, ASP conf. ser.

V tekstovuyu formu svedena interesnaya diskussiya po zvezdoobrazovaniyu.

Vtoraya chast' diskusii, posvyashennaya zvezdoobrazovaniyu na bol'shih krasnyh smesheniyah, nahoditsya zdes'.


item arxiv:0711.1843 Poisk diffuznyh polos v spektrah obolochek post-AGB zvezd (A search for diffuse bands in the circumstellar envelopes of post-AGB stars).
Authors: R. Luna et al.
Comments: A&A, 25 pages

Priroda diffuznyh polos poglosheniya ostaetsya nereshennoi problemoi fiziki mezhzvezdnoi sredy. V opticheskom i infrakrasnom diapazonah sovremennye katalogi naschityvayut uzhe bolee dvuhsot takih polos, no vopros, kakie imenno molekuly otvetstvenny za pogloshenie, ostaetsya otkrytym. Naibolee veroyatnymi kandidatami nazyvayut slozhnye ogranicheskie molekuly. Sushestvuet principial'naya raznica mezhdu polosami poglosheniya, formiruyushimisya v diffuznoi MZS i v protyazhennyh obolochkah post-AGB zvezd. Fizicheskie usloviya (plotnost', uroven' ionizacii, himicheskii sostav gaza) v etih sluchayah sovershenno razlichny. Opisat' sostoyanie diffuznoi MZS na osnove nablyudenii chasto ochen' trudno, zato opredelit' sostav gaza i pyli v obolochkah post-AGB zvezd v poslednie gody stalo vozmozhnym. Nablyudeniya diffuznyh polos poglosheniya v atmosferah post-AGB zvezd (esli oni tam est'!) mogli by proyasnit' obshii mehanizm formirovaniya diffuznyh polos v MZS. Imenno etoi celi posvyashena dannaya rabota.

Nablyudeniya provodilis' v techenie 1993-2003 gg na teleskopah WHT 4.2m, TNG 3.58m, VLT 8m, NTT 3.5m, ESO 1.52m. Avtorami byli polucheny spektry vysokogo razresheniya dlya 33 post-AGB zvezd v opticheskom intervale dlin voln 4000-10000 A. Tipichnoe vremya ekspozicii sostavilo okolo poluchasa, otnoshenie S/N 20-200. Cel'yu nablyudenii byl poisk devyati naibolee sil'nyh difuznyh polos poglosheniya na dlinah voln 5780, 5797, 5850, 6196, 6284, 6379, 6614, 6993 i 7224 A. Ni odnoi iz devyati polos v obolochkah 33 post-AGB zvezd obnaruzheno ne bylo. Razdelenie zvezd na gruppy v zavisimosti ot spektral'nogo klassa i himicheskogo sostava obolochki (uglerodnye ili kislorodnye zvezdy) takzhe ne pozvolilo vyyavit' kakoi-libo korrelyacii. Po mneniyu avtorov, diffuznye polosy v obolochkah post-AGB zvezd libo otsutstvuyut voobshe, libo slishkom slaby dlya togo, chtoby ih mozhno bylo zafiksirovat' sovremennymi priborami. Himicheskii sostav zvezdnyh obolochek i usloviya, otlichnye ot tipichnyh uslovii v diffuznoi MZS, veroyatno, privodyat k tomu, chto molekuly, vyzyvayushie diffuznye polosy, v atmosferah post-AGB zvezd prosto ne formiruyutsya.


item arxiv:0711.2016 Vershina krasnoi vetvi gigantov (The Tip of the Red Giant Branch).
Authors: M. Bellazzini1
Comments: Mem.SAI, 8 pages

Nebol'shoi soderzhatel'nyi obzor metoda TRGB (the Tip of the Red Giant Branch), nezamenimogo v opredelenii rasstoyanii do galaktik raznyh morfologicheskih tipov. Predstavlen kratkii obzor poslednih rezul'tatov, kasayushihsya kalibrovki vershiny krasnoi vetvi gigantov v kachestve "standartnoi svechi". Obsuzhdaetsya dostignutoe soglasie sredi nezavisimyh empiricheskih kalibrovok etogo metoda.


item arxiv:0711.2166 Solnechnoe obilie indiya (On the solar abundance of indium).
Authors: N. Vitas et al.
Comments: MNRAS, 7 pages

Indii - himicheskii element s rekordnym otlichiem solnechnogo i meteoritnogo obilii. Meteoritnoe znachenie sostavlyaet A(In)=0.8 +/- 0.03, v to vremya kak soderzhanie indiya v solnechnoi fotosfere na 0.8 dex bol'she. Chtoby ob'yasnit' raznicu, avtory raboty zanovo rassmotreli metodiku nahozhdeniya solnechnogo obiliya. Analiz pokazal, chto liniya 4511.3 A, obychno rassmatrivaemaya kak liniya In I, vyzvana otnyud' ne indiem, a drugim, ne indentificirovannym poka elementom (predpolozhitel'no, ionom s vysokoi energiei vozbuzhdeniya). Uchet etih popravok privodit k horoshemu soglasiyu mezhdu solnechnym i meteoritnym soderzhaniem indiya, ustranyaya vyshenazvannoe protivorechie.


arxiv:0711.2362 Kak vzaimodeistvie v dvoinyh vliyaet na zvezdnyi populyacionnyi sintez (How binary interactions affect stellar population synthesis)
Authors: Zhongmu Li, Zhanwen Han
Comments: 24 pages, 14 figures

V astrofizike aktivno primenyaetsya t.n. Populyacionnyi sintez. Odnim iz osnovnyh napravlenii, v kotoryh primenyaetsya eta metodika, yavlyaetsya issledovanie zvezdnogo sostava galaktik po ih integral'nym spektram. Iznachal'no pri takih rabotah ispol'zovalis' tol'ko spektry odinochnyh zvzd. Odnako okolo poloviny zvezd vhodit v sostav dvoinyh sistem (ili sistem bol'shei kratnosti). Otnositel'no nedavno nachali uchityvat' i eto. V stat'e dostatochno detal'no rassmatrivaetsya etot vopros i demonstriruyutsya novye rezul'taty.

Nesmotrya na to, chto nekotorye parametry "plyvut" posle ucheta dvoinyh, avtory polagayut, chto rezul'taty, poluchenye pri ispol'zovanii lish' odinochnyh zvezd vpolne horoshi dlya mnogih celei. Krome togo, oni pokazyvayut, kak ih mozhno "perenormirovat'", chtoby uchest' vklad dvoinyh.


Vypusk 171. 17-31 oktyabrya 2007

arxiv:0710.4003 YREC: The Yale Rotating Stellar Evolution Code (YREC: The Yale Rotating Stellar Evolution Code)
Authors: P. Demarque, D.B. Guenther, L.H. Li, A. Mazumdar, C.W. Straka
Comments: 10 pages, 2 figures, ApSS accepted

Dano opisanie odnogo iz kodov, opisyvayushih evolyuciyu normal'nyh zvezd. Sushestvuet neskol'ko modifikacii etogo nabora programm. Nekotorye iz nih dostatochno detal'ny dlya prilozheniya k astroseismologii i issledovaniyam vnutrennego stroeniya Solnca.


Vypusk 170. 01-16 oktyabrya 2007

item arxiv:0709.4551 Spektral'naya biblioteka zvezd v infrakrasnom diapazone: III. Spektry v polose J (A Near-Infrared Stellar Spectral Library: III. J-Band Spectra)
Authors: Arvind C. Ranade et al.
Comments: BASI, 26 pages

Predstavleny rezul'taty nablyudenii, provedennyh na indiiskom infrakrasnom 1.2 m teleskope GIRT (Gurushikhar Infrared Telescope). Avtorami privedena biblioteka infrakrasnyh spektrov dlya 126 zvezd spektral'nyh tipov O5-M8 i klassov svetimosti I-V. Vse spektry byli polucheny v polose J s razresheniem 12.5 A. Dannaya publikaciya yavlyaetsya tret'ei v serii rabot na etu temu. Ranee opublikovany spektry 135 zvezd v polose H s razresheniem 16 A (Ranade et al, 2004) i spektry 114 zvezd v polose K s razresheniem 22 A (Ranade et al., 2007). Polnost'yu biblioteka spektrov zvezd v infrakrasnyh polosah J, H & K summirovana v v vide ASCII tablic i dostupna na avtorskom veb-saite po adresu http://vo.iucaa.ernet.in/~voi/NIR_Header.html


arxiv:0710.1181 Evolyuciya i sud'ba sverhmassivnyh zvezd (On the evolution and fate of supermassive stars)
Authors: L.R. Yungelson et al.
Comments: 26 pages, 15 figures, accepted by Astronomy & Astrophysics

Bol'shaya stat'ya, posvyashennaya detal'nomu issledovaniyu evolyucii zvezd s solnechnoi metallichnost'yu i massoi ot 60 do 1000 solnechnyh. Ochen' massivnye zvezdy mogut obrazovyvat'sya v plotnyh molodyh skopleniyah za schet "slipaniya". Ih chasto obsuzhdayut kak praroditelei chernyh dyr promezhutochnyh mass, svyazannyh s ul'tramoshnymi istochnikami.

Osnovnoi rezul'tat takov, chto chernye dyry poluchayutsya iz zvezd i iznachal'nymi massami menee 250 solnechnyh i ot 800 do 1000 (v promezhutke proishodit polnyi razlet yadra bez obrazovaniya kompaktnogo ostatka), no massy etih chernyh dyr ne veliki (menee 70 solnechnyh), t.e. dlya ob'yasneniya ul'tramoshnyh istochnikov oni ne podoidut.


arxiv:0710.1734 Kogda zvezdy stalkivayutsya (When Stars Collide)
Authors: E. Glebbeek O. R. Pols
Comments: 8 pages, 5 figures to appear in the proceedings for "Unsolved Problems in Stellar Physics", Cambridge, 2-6 July 2007

Inogda zvezdy delayut eto. Oni slivayutsya. Proishodit eto, naprimer, v plotnyh sopleniyah. V rezul'tate poyavlyayutsya zvezdy, sil'no otlichayushiesya ot svoih sobrat'ev, obrazovavshihsya tradicionnym obrazom. Obychno oni yarche i goryachee, chem obychnye zvezdy toi zhe massy.

Avtory rassmatrivayut evolyuciyu zvezd, obrazovavshihsya v rezul'tate sliyanii.


Vypusk 169. 19-30 sentyabrya 2007

miniobzor arxiv:0709.2310 Modelirovanie spektrov spiral'nyh galaktik (Modelling the SEDs of spiral galaxies)
Authors: C. C. Popescu, R.J. Tuffs
Comments: 10 pages, invited lecture to appear in Proceedings of the lectures given at the Les Houche Winter School "Astronomy in the submillimeter and far infrared domains with the Herschel Space Observatory"

Dlya kolichestvennogo opisaniya tempa zvezdoobrazovaniya v spiral'nyh galaktikah, raspredeleniya v nih gaza i zvezd, ih neprozrachnosti dlya izlucheniya trebuetsya soglasovannoe modelirovanie ih spektrov (SED) v bol'shom diapazone dlin voln: ot ul'trafioletovogo i opticheskogo do infrakrasnogo i submillimetrovogo. Klyuchevym momentom takogo modelirovaniya stanovitsya model' pyli (opticheskih svoistv pylevyh chastic i ih raspredeleniya po razmeram), poskol'ku pyl' pogloshaet opticheskoe izluchenie zvezd i pereizluchayut ego v infrakrasnom i submillimetrovom diapazonah. V dannoi lekcii avtory opisyvayut razrabotannuyu imi metodiku modelirovaniya spektrov spiral'nyh galaktik i ee prilozheniya. Bolee podrobnyi obzor opublikovan v rabote Popescu & Tuffs (2005, AIPC 761, 155).


arxiv:0709.2353 Spektral'nyi atlas zvezd skopleniya omega Centauri, soshedshih s glavnoi posledovatel'nosti: kinematika, evolyuciya, obogashenie tyazhelymi elementami i mezhzvezdnaya sreda (A spectral atlas of post-main-sequence stars in omega Centauri: kinematics, evolution, enrichment and interstellar medium)
Authors: Jacco Th. van Loon et al.
Comments: 24 pages, accepted for publication in MNRAS

Omega Centauri (NGC5139) - horosho izvestnoe isklyuchenie iz pravila o tom, chto sharovye skopleniya predstavlyayut soboi himicheski odnorodnye gruppy zvezd pochti odinakovogo vozrasta. V omega Cen vse ne tak: zvezdy razdeleny na dve gruppy s metallichnost'yu [Fe/H]~ -1.8 dex i [Fe/H]~ -0.8 dex, i dlya ob'yasneniya etogo predpolagayut, chto zvezdoobrazovanie v omega Cen proishodilo po krainei mere na protyazhenii 2 mldr let. No voprosy ostayutsya, i potomu nuzhny nablyudeniya. V dannoi rabote predstavlen analiz opticheskih spektrov bolee 1500 zvezd skopleniya. Avtorami izmereny radial'nye skorosti zvezd, ih effektivnye temperatury i metallichnosti.


item arxiv:0709.2780 Zvezdnyi sostav roditel'skih galaktik lacertid na malyh krasnyh smesheniyah po rezul'tatam mnogocvetnoi fotometrii (The stellar content of low redshift BL Lac host galaxies from multicolour imaging)
Authors: T. Hyvonen et al.
Comments: 15 pages, A&A in press

Lacertidy (BL Lac) - klass aktivnyh galakticheskih yader (AGN), harakterizuemyi izlucheniem s ploskim spektrom i cil'noi peremennost'yu vo vseh diapazonah. Opticheskie i infrakrasnye issledovaniya mnogih avtorov pokazali, chto roditel'skimi galaktikami blizkih (z < 0.5) lacertid yavlyayutsya yarkie giganskie ellipticheskie galaktiki. Avtory dannoi raboty podtverzhdayut etot vyvod. V stat'e predstavleny rezul'taty mnogocvetnoi fotometrii (U, B, V, R, H) 18 lacertid na krasnyh smesheniyah z < 0.3 Podtverzhdeno, chto roditel'skie galaktiki lacertid v celom golubee obychnyh ellipticheskih galaktik i imeyut bolee shirokii razbros cvetovyh pokazatelei. Oba faktora govoryat o sushestvovanii v lacertidah molodogo zvezdnogo naseleniya, o vzaimosvyazi processov zvezdoobrazovaniya i aktivnosti galakticheskih yader.


arxiv:0709.2739 Scenarii obrazovaniya shirokih i tesnyh dvoinyh sistem (Formation Scenario for Wide and Close Binary Systems)
Authors: Masahiro N. Machida, Kohji Tomisaka, Tomoaki Matsumoto, Shu-ichiro Inutsuka
Comments: 45 pages,12 figures, Submitted to ApJ

Avtory provodyat trehmernoe chislennoe modelirovanie evolyucii zamagnichennogo molekulyarnogo oblaka s cel'yu vyyasneniya togo, kak obrazuyutsya dvoinye zvezdy. Avtory predskazyvayut, chto u zvezd v ochen' molodyh gruppah dolzhno nablyudat'sya dva pika v raspredelenii po bol'shim poluosyam orbit dvoinyh.

Sm. takzhe arxiv:0709.2886 i arxiv:0709.2887, posvyashennye analogichnym issledovaniyam - obrazovanie zvezd. Zdes' avtory detal'no issleduyut rol' magnitnyh polei pri kollapse oblaka. Vyvody otlichayutsya ot poluchennyh v opisannoi vyshe stat'e.


arxiv:0709.3052 Dostup k modelyam zvezdnyh populyacii v Virtual'noi observatorii (Access to Stellar Population Models in the Virtual Observatory)
Authors: Igor Chilingarian
Comments: 2 pages, 1 figure, Stellar Populations as Building Blocks of Galaxies, Proceedings of IAU Symposium #241. Edited by A. Vazdekis and R. F. Peletier. Cambridge: Cambridge University Press, 2007, pp.177-178

Sravnivayutsya dva podhoda pri organizacii dostupa k dannym o zvezdnyh populyaciyah v Virtual'noi observatorii. K sozhaleniyu, zametka ochen' korotkaya, poetomu, po suti, prihoditsya dovol'stvovat'sya lish' vyvodami avtora. Vse detali ostayutsya za bortom.


arxiv:0709.3118 Ogranicheniya na kiki belyh karlikov v sharovyh skopleniyah: II. Nablyudatel'naya znachimost' (Constraining white-dwarf kicks in globular clusters : II. Observational Significance)
Authors: Jeremy S. Heyl
Comments: 5 pages, 4 figures, submitted to MNRAS letters

Zabavno, chto belye karliki, kak neitronnye zvezdy i chernye dyry, mogut tozhe poluchat' "tychki". Svyazano eto s nesimmetrichnym sbrosom massy gigantami. Effekt ne ochen' velik, no mozhno postarat'sya ego zametit'. Proshe vsego eto sdelat' v sharovyh skopleniyah. Esli kik est', to belye karliki budut raspredeleny ne tak, kak ih praroditeli. V samom dele, takoi effekt nablyudayut. Avtor obsuzhdaet razlichnye varianty raspredelenii, kotorye mogli by rasskazat' nam bol'she o kikah belyh karlikov.


item arxiv:0709.3255 Novaya kalibrovka sootnosheniya period-svetimost' dlya cefeid Galaktiki v fil'trah ot B do K i sravnenie s analogichnym sootnosheniem dlya cefeid BMO (A new calibration of Galactic Cepheid Period-Luminosity relations from B to K bands, and a comparison to LMC PL relations)
Authors: P. Fouque et al.
Comments: 12 pages, A&A in press

Avtorami byli izucheny 59 cefeid s izvestnymi parallaksami s cel'yu otkalibrovat' sootnoshenie period-svetimost' dlya cefeid Galaktiki i sravnit' ego s analogichnym sootnosheniem dlya cefeid Bol'shogo Magellanova Oblaka (BMO). Nablyudeniya provodilis' v semi fil'trah (B, V, Rc, Ic, J, H, Ks), a rasstoyaniya do cefeid byli nezavisimo izmereny pyat'yu sposobami. Sushestvennyh otlichii mezhdu naklonami v sootnosheniyah period-svetimost' dlya cefeid Galaktiki i BMO v spektral'nom diapazone ot B do K naideno ne bylo. Po-vidimomu, dannoe sootnoshenie imeet universal'nyi naklon i ne zavisit ot metallichnosti galaktiki.


obzor arxiv:0709.3732 Kompaktnye ob'ekty v sharovyh skopleniyah (Compact objects in globular clusters)
Authors: Thomas J. Maccarone, Christian Knigge
Comments: 20 pages, review article accepted for October edition of Astronomy & Geophysics. A more colorful version of this paper with a few extra figures will appear in A&G. The scientific content is the same in both versions

Format stat'i "prostovatyi", zato soderzhanie ochen' i ochen'. Zasluzhivaet prochteniya.

Avtory dayut polnyi obzor po nablyudeniyam razlichnyh kompaktnyh ob'ektov v sharovyh skopleniyah. Eto i radionablyudeniya millisekundnyh pul'sarov, i rentgenovskie nablyudeniya razlichnyh istochnikov v dvoinyh sistemah, i koe-chto drugoe.

Kak izvestno, sharovye skopleniya - eto dostatochno starye ob'ekty. Poetomu molodyh neitronnyh zvezd tam malo. Kazalos' by, i aktivnyh kompaktnyh ob'ektov tam dolzhno byt' men'she. V deistvitel'nosti vse ne tak prosto. Za schet vzaimodeistvii drug s drugom zvezdy mogut obrazovyvat' pary. V itoge, temp obrazovaniya nekotoryh tipov ob'ektov v sharovyh skopleniyah raz v sto vyshe, chem v diske Galaktiki. Poetmou nekotorye sharoviki pryamo-taki napichkany inteersnymi sistemami. Pro vse eto mozhno prochest' v obzore (zaodno otmechu, chto zhurnal Astronomy & Geophysics voobshe otlichaetsya interesnymi obzorami).


miniobzor arxiv:0709.3808 Ot zvezd k yadram (From stars to nuclei)
Authors: Georges Meynet
Comments: 8 pages, 2 figures, be published in "European Physical Journal: Special Topics"

Nebol'shoi obzor pro evolyuciyu zvezd s tochki zreniya opisaniya yadernyh reakcii v iz nedrah.


obzor arxiv:0709.4220 Processy neteplovogo izlucheniya v massivnyh dvoinyh (Non-thermal emission processes in massive binaries)
Authors: M. De Becker
Comments: 47 pages, 5 postscript figures, accepted for publication in Astronomy and Astrophysics Review. Astronomy and Astrophysics Review, in press

Ya dumayu, chto seichas, kogda AGILE uzhe letaet, a GLAST vot-vot zapustyat, obzor po neteplovomu izlucheniyu massivnyh dvoinyh ochen' umesten (hotya rech' idet ne tol'ko o gamma-izluchenii, no i radio, optike i rentgene). Kak i vse, po suti, obzory dlya A&AR napisano vse ochen' ponyatno (po-krainei mere dlya studentov ne samyh mladshih kursov sootvetstvuyushih special'nostei). Pri etom est' vse srazu: i fizika, i nablyudeniya, i vse vokrug.


arxiv:0709.4526 Issledovanie proishozhdeniya magnitnogo polya neitronnyh zvezd: magnitnye svoistva OV-zvezd-praroditelei (Exploring the origin of neutron star magnetic field: magnetic properties of the progenitor OB stars)
Authors: V. Petit, G.A. Wade, L. Drissen, T. Montmerle
Comments: 5 pages, 4 figures 40 Years of Pulsars conference: Millisecond Pulsars, Magnetars and More. McGill University, Montreal, Canada, August 12-17, 2007.

Proishozhdenie magnitnyh polei magnitarov ostaetsya zagadkoi. To li oni generyatsya na stadii protoneitronnoi zvezdy, to li zvezdy-praroditeli sami byli sil'no zamagnicheny, tak chto posle kollapsa i kompaktnye ob'ekty okazalis' s superpolyami. Avtory issleduyut vtoruyu vozmozhnost', pytayas' izmerit' polya massivnyh OV-zvezd. Vyvod avtorov lyubopyten. Oni polagayut, chto vtoraya vozmozhnost' (kollaps sil'no zamagnichennyh zvezd) ne prohodit ne potomu, chto sil'no zamagnichennyh massivnyh zvezd malo, a potomu, chto ih mnogo! Iz vos'mi issledovannyh zvezd tri okazalis' s sil'nymi polyami.



Vypusk 168. 11-18 sentyabrya 2007

item arxiv:0709.1073 Sootnoshenie cvet-metallichnost' i bimodal'nost' cvetovyh diagramm vnegalakticheskih sharovyh skoplenii (On the Metallicity-Color Relations and Bimodal Color Distributions in Extragalactic Globular Cluster Systems)
Authors: Michele Cantiello, John P. Blakeslee
Comments: ApJ accepted

Na osnove mnogoletnih issledovanii slozhilos' predstavlenie, chto sharovye skopleniya (ShS) - otnositel'no prostye sistemy, v kotoryh zvezdy sformirovalis' prakticheski odnovremenno. No odnoi iz zagadok evolyucii ShS ostaetsya bimodal'nost' cvetovyh diagramm. Dlya ob'yasneniya etogo effekta prishlos' iskusstvenno predpolozhit', chto formirovanie ShS proishodilo s samoobogasheniem, t.e. samye massivnye zvezdy v oblake protoskopleniya evolyucionirovali bystro i obogashali mezhzvezdnuyu sredu tyazhelymi elementami, iz kotoroi uspevalo sformirovat'sya vtoroe pokolenie zvezd s bol'shei metallichnost'yu. V takom scenarii bimodal'nost' cvetovyh diagramm ShS - pryamoe sledstvie bimodal'nosti metallichnosti mezhzvezdnoi sredy protoskopleniya. Eta shema imeet mnogochislennye protivorechiya, poetomu predlagayutsya i drugie al'ternativnye varianty. V chastnosti, v dannoi rabote issleduetsya, kak budut vyglyadet' cvetovye diagrammy ShS v predpolozhenii nelineinogo sootnosheniya cvet-metallichnost'. V predpolozhenii edinogo gaussovogo raspredeleniya metallichnosti avtory raboty uverenno vosproizvodyat nablyudaemye bimodal'nye cvetovye diagrammy. Poskol'ku odnoznachnosti v interpretacii prirody bimodal'nosti po-prezhnemu net, vopros ostaetsya otkrytym.


arxiv:0709.1275 Avtomaticheskii poisk galakticheskih zvezdnyh skoplenii po dannym mnogocvetnyh obzorov: I. Obnaruzhenie 15 novyh rasseyannyh skoplenii v napravlenii anticentra Galaktiki (Automated search for galactic star clusters in large multiband surveys: I. Discovery of 15 new open clusters in the Galactic anticenter region)
Authors: E. V. Glushkova, S.E. Koposov, I.Yu. Zolotukhin
Comments: submitted to A&A

Seichas v astronomii zaicev mnogo, a ... issledovatelei malo. T.e., situaciya takova, chto est' ogromnoe kolichestvo horoshih dannyh, lezhashih v otkrytom dostupe, s kotorymi mozhno rabotat'. Naprimer, mozhno iskat' novye skopleniya. Dlya etogo nuzhno sozdat' horoshii soft - i vpered!

Avtory ispol'zuyut svoi metod poiska rasseyannyh skoplenii. Kak vidno, metod ves'ma effektiven. V kachestve illyustracii avtory proveli poisk skoplenii v napravlenii galakticheskogo anticentra po dannym obzora 2MASS. Naideno 15 novyh skoplenii.


item arxiv:0709.1473 Konvertaciya svetimosti v linii H_alpha v temp zvezdoobrazovaniya (Converting Halpha luminosities into SFRs)
Authors: Jan Pflamm-Altenburg et al.
Comments: Accepted by ApJ

Dlya ocenki tekushego tempa zvezdoobrazovaniya (ZO) v galaktikah shiroko ispol'zuetsya lineinoe sootnoshenie mezhdu svetimost'yu v linii H_alpha i tempom ZO, predlozhennoe dlya spiral'nyh galaktik v rabote Kennicutt et al (1994). Takoi pereschet osnovan na predpolozhenii o neizmennosti NFM zvezd i ee nezavisimosti ot tempa ZO. Avtory dannoi raboty pokazyvayut, chto vstrechayushayasya v literature ekstrapolyaciya dannogo sootnosheniya na oblast' karlikovyh galaktik privodit k nedoocenke tempa ZO v etih galaktikah na tri poryadka, poskol'ku dlya malyh svetimostei v linii H_alpha lineinost' zakona narushaetsya. Ne isklyucheno, chto utochnenie dannoi zavisimosti povlechet za soboi peresmotr obshego ponimaniya o tom, kak proishodit zvezdoobrazovanie v karlikovyh galaktikah i, sledovatel'no, peresmotr kosmologicheskoi istorii zvezdoobrazovaniya v celom.


Vypusk 167. 25 avgusta - 10 sentyabrya 2007

arxiv:0708.3819 Smeshenie linii, assimetriya linii i opredelenie otnosheniya izotopov 6Li/7Li (Line shift, line asymmetry, and the 6Li/7Li isotopic ratio determination)
Authors: Roger Cayrel, et al.
Comments: Accepted for publication on A&A Letters

Litii - sovershenno unikal'nyi himicheskii element, sostoyashii iz dvuh izotopov 6Li i 7Li. Sintez litiya proishodit tremya spososobami: srazu posle Bol'shogo Vzryva v processe pervichnogo nukleosinteza (tol'ko 7Li), v processe zvezdnoi evolyucii na stadii AGB - asimptoticheskoi vetvi gigantov (tol'ko 7Li) i pri vzaimodeistvii kosmicheskih luchei s atomami mezhzvezdnoi sredy (v osnovnom 6Li). Poskol'ku 6Li sinteziruetsya gorazdo pozzhe 7Li, otnoshenie izotopov litiya 6Li/7Li v staryh malometallichnyh zvezdah galo sluzhit odnim iz vazhnyh nablyudatel'nyh testov teorii pervichnogo nukleosinteza. Avtory dannoi stat'i (polovina iz nih - vsemirno izvestnye uchenye) dvumya razlichnymi sposobami izuchili soderzhanie izotopov litiya v atmosfere malometallichnoi zvezdy HD 74000, prinadlezhashei galo nashei Galaktiki. Rezul'taty etogo analiza, osnovannogo na novom metode razdeleniya blendirovannyh linii izotopov 6Li i 7Li, pokazali, chto dlya vseh ranee opublikovannyh rabot mozhno s bol'shoi uverennost'yu govorit' o sistematicheskoi pereocenke soderzhaniya izotopa 6Li. Po ocenke avtorov, soderzhanie 6Li v atmosfere zvezdy HD 74000 (metallichnost' [Fe/H]=- 2.0 dex) ne prevyshaet odnogo-dvuh procentov ot soderzhaniya izotopa 7Li. Esli rezul'tat podobnogo analiza budet podtverzhden dlya statisticheski znachimogo chisla malometallichnyh zvezd, ischeznet neobhodimost' poiska variantov sinteza 6Li na rannih etapah evolyucii Vselennoi i nablyudatel'noe ogranichenie teorii pervichnogo nukleosinteza budet nadezhno podtverzhdeno.


obzor arxiv:0708.3848 Vtorye zvezdy (The Second Stars)
Authors: Falk Herwig
Comments: Biermann award 2004 lecture, AG meeting, Prague (2005RvMA...18...21)

"Vtorye zvezdy" - eto svetila, voznikshie srazu posle pervyh. Pervye sostoyali tol'ko iz pervichnogo veshestva, poetomu v osnovnom byli ochen' massivnymi i zhili nedolgo. Seichas takih net (esli, konechno, gde-to ne ostalos' dostatochnoe kolichestvo ploho peremeshannogo gaza). "Vtorye zvezdy" obrazovyvalis' iz uzhe slegka obogashennogo tyazhelymi elementami veshestva. Poetomu oni mogli byt' malomassivnymi, a znachit mogli dozhit' do nashih dnei. T.o., oni yavlyayutsya unikal'nymi "svidetelyami epohi". O tom, chto oni rasskazyvayut nam - v stat'e.


miniobzor arxiv:0708.4175 Spitcerovskii vzglyad na planetarnye tumannosti (Spitzer's View of Planetary Nebulae)
Authors: Joseph L. Hora
Comments: 8 pages, 2 figures, invited review to appear in the proceedings of the conference "Asymmetrical Planetary Nebulae IV", eds. R.L.M. Corradi, A. Manchado & N. Soker

Nebol'shaya stat'ya, v kotoroi dana svodka dannyh po planetarnym tumannostyam, poluchennyh na kosmicheskom infrakrasnom teleskope imeni Spitcera.

Drugoi poleznyi korotkii obzor iz togo zhe sbornika (uzhe yasno, chto takim miniobzorov budet mnogo) posvyashen asimmetrii planetarnyh tumannostei.


arxiv:0709.0029 Novye predel'no malometallichnye zvezdy v galo Galaktiki (New Extremely Metal-Poor Stars in the Galactic Halo)
Authors: Judith G. Cohen,et al.
Comments: Accepted to the ApJ

Avtorami predstavlen detal'nyi analiz spektrov vysokogo razresheniya novyh vos'mi zvezd galo nashei Galaktiki, imeyushih predel'no malye metallichnosti [Fe/H] < -3.5 dex. Pohozhe na to, chto pri ochen' malyh metallichnostyah stohastichnost' vzryvov sverhnovyh II i neeffektivnost' peremeshivaniya mezhzvezdnoi sredy okazyvayut sushestvennoe vliyanie na nablyudaemye otnositel'nye soderzhaniya himicheskih elementov v atmosferah etih zvezd. Dannye takogo roda yavlyayutsya vazhnym istochnikom informacii o nachal'nyh stadiyah evolyucii Galaktiki, a takzhe sluzhat testom dlya zvezdnoi teorii nukleosinteza.


obzor arxiv:0709.0081 Fotosfernye processy i magnitnye trubki (Photospheric processes and magnetic flux tubes)
Authors: O. Steiner
Comments: 48 pages, 33 figures, Lecture notes

Lekcii posvyasheny processam v poverhnostnyh sloyah Solnca. Dannye nablyudenii pokazyvayut inteersnye melkomasshtabnye struktury. S pomosh'yu chislennogo modelirovaniya udaetsya ponyat', chto zhe my nablyudaem.


arxiv:0709.0202 Mogut li ochen' massivnye zvezdy izbezhat' sverhnovoi s neustoichivost'yu k rozhdeniyu par? (Can very massive stars avoid Pair-instability Supernovae?)
Authors: S. Ekstroem, G. Meynet, A. Maeder
Comments: to be published in the conference proceedings of First Stars III, Santa Fe, 2007

Massivnye zvezdy maloi metallichnosti v nekotorom diapazone mass dolzhny teryat' svoyu ustoichivost' iz-za rozhdeniya par v yadre, chto privodit k specificheskomu vzryvu sverhnovoi. Takie sverhnovye dolzhny ostavlyat' harakternye "otpechatki pal'cev" iz-za osobennostei sostava vybrasyvaemogo veshestva. "Uliki" ne obnaruzheny. Eto mozhet byt' svyazano s tem, chto vse-taki takie vzryvy ne proishodyat. Avtory rassmatrivayut nekotorye varianty, dlya togo, chtoby zvezdy mogli izbezhat' takoi neustoichivosti. Pohozhe, chto variant naiden.


arxiv:0709.0485 Rasstoyanie do tumannosti Oriona (The distance to the Orion Nebula)
Authors: K. M. Menten et al.
Comments: 13 pages, 3 figures, to appear in Astronomy & Astrophyiscs

S pomosh'yu VLBA izmeren trigonometricheskii parallaks dlya neskol'kih chlenov skopleniya v tumannosti Oriona. Rasstoyanie ravno 414+/-7 pk.


arxiv:0709.0829 Dlinnye gamma-vspleski ot dvoinyh zvezd: ubegayushie Vol'f-Raie praroditeli (Long GRBs from binary stars: runaway, Wolf-Rayet progenitors)
Authors: M.Cantiello, S.-C.Yoon, N.Langer, M.Livio
Comments: 6 pages, To appear in the proceedings of the conference "Unsolved problems in stellar physics" - Cambridge, July 2007

Dlya poyavleniya dlinnogo gamma-vspleska, chto v naibolee populyarnom scenarii svyazyvaetsya s kollapsom yadra dostatochno massivnoi zvezdy, neobhodimo bystroe vrashenie yadra zvezdy. Obychno zvezdy dostatochno effektivno zamedlyayutsya. Raskrutit' zvezdu mozhno v tesnoi dvoinoi sisteme. Krome togo, bylo predlozheno, chto pri maloi metallichnosti zvezdy ostayutsya dostatochno bystrovrashayushimisya. V dannoi stat'e predstavlen analiz situacii, v kotoroi malometallichnaya zvezda vhodit v tesnuyu dvoinuyu sistemu.

Vo-pervyh, pokazano, chto v takoi dvoinoi mozhno poluchit' usloviya, pri kotoryh vtoraya (menee massivnaya) zvezda dast gamma-vsplesk. Vo-vtoryh, sistema raspadaetsya posle pervogo vzryva, poetomu mozhno ozhidat', chto predsverhnovaya budet ubegayushei zvezdoi. Eto znachit, chto ona proidet neskol'ko sot parsek do porozhdeniya vspleska. Nakonec, poskol'ku skoree vsego napravlenie dzheta budet perpendikulyarno skrosti zvezdy , mozhno sdelat' predskazaniya otnositel'no svoistv sredy vokrug vzryvayusheisya zvezdy. Eto vazhno dlya opisaniya svoistv poslesvechenii (oreolov) gamma-vspleskov.


Vypusk 166. 14-24 avgusta 2007

arxiv:0708.2100 Prozhektornye dvoinye - novyi klass fotometricheskih dvoinyh zvezd (Beaming Binaries - a New Observational Category of Photometric Binary Stars)
Authors: Shay Zucker, Tsevi Mazeh, Tal Alexander
Comments: 15 pages, 4 figures, accpeted for publication in The Astrophysical Journal

V 2003 godu Loeb i Gaudi otmetili, chto orbital'noe dvizhenie zvezdy za schet relyativistskih effektov mozhet privodit' v slabomu, no dostatochnomu dlya registracii na budushih kosmicheskih missiyah, izmeneniyu bleska. V novoi stat'e avtory detal'nee rassmatrivayut nekotorye effekty v prilozhenii k missiyam CoRot i Kepler. Hotya rech' idet ob izmenenii bleska na neskol'ko sotyh dolei procenta, tem ne menee eti sputniki sposobny zaregistrirovat' effekt. Sootvetstvenno, esli on budet obnaruzhen (a eto lish' vopros tehniki), to mozhno budet vydelit' novyi tip peremennosti svyazannyi s relyativistskoi fokusirovkoi.


arxiv:0708.3016 Obrazovanie zvezd i planet s ALMA: obzor (Star and Planet Formation with ALMA: an Overview)
Authors: Ewine F. van Dishoeck, Jes K. Jorgensen
Comments: Invited review, 8 pages, 5 figures; to appear in the proceedings of "Science with ALMA: a New Era for Astrophysics". Astrophysics & Space Science, in press

Mnogie, navernoe, videli v EvroN'yus syuzhet pro proekt ALMA. V stat'e daetsya kratkii obzor po odnomu iz napravlenii issledovanii na ALMA.

Odna iz osnovnyh zadach proekta - prolit' svet na formirovanie zvezd i planet. Ozhidaetsya, chto mozhno budet rassmotret' protoplanetnye diski s prostranstvennym razresheniem do 1 a.e.!


Vypusk 165. 01-13 avgusta 2007

obzor arxiv:0708.1499 Processy perenosa v zvezdah: diffuziya, vrashenie, magnitnye polya i vnutrennie volny (Transport processes in stars: diffusion, rotation, magnetic fields and internal waves)
Authors: Suzanne Talon
Comments: 50 pages, proceedings of the Aussois school "Stellar Nucleosynthesis: 50 years after B2FH"

Bol'shoi obzor po processam perenosa v zvezdah. Na moi vzglyad, eto udachnoe sochetanie mnozhestva prostyh formul, bol'shogo chisla poyasnyayushih risunkov i tp.


Vypusk 164. 20-31 iyulya 2007

obzor arxiv:0707.3514 Teoriya obrazovaniya zvezd (Theory of Star Formation)
Authors: Christopher F. McKee, Eve C. Ostriker
Comments: 120 pages, to appear in ARAA.

Obsuzhdayutsya vse aspekty obrazovaniya zvezd.


soderzhanie arxiv:0707.4150 Simpozium MAS 241 - Zvezdnye populyacii kak stroitel'nye bloki galaktik (IAU Symposium 241 - Stellar Populations as Building Blocks of Galaxies)
Authors: A. Vazdekis, R.F. Peletier
Comments: This is the table of contents of the upcoming proceedings of IAU Symposium 241. The book will appear in September, from Cambridge University Press, and will also be available electronically

Osen'yu poyavitsya sbornik trudov sootvetstvuyushego simpoziuma. Vse eto bogatstvo mozhno budet skachat' zdes'. A poka mozhno posmotret' na vyhodnye dannye knigi, soderzhanie i vvodnuyu stat'yu.


obzor arxiv:0707.4293 Modelirovanie plotnyh zvezdnyh sistem (Modeling Dense Stellar Systems)
Authors: Piet Hut, Shin Mineshige, Douglas C. Heggie, Junichiro Makino
Comments: 23 pages, to appear in Prog. Theor. Phys

Rassmotreny razlichnye aspekty modelirovaniya tesnyh zvezdnyh sistem, v kotoryh vozmozhny chastye vzaimodeistviya zvezd (zahvaty, obmeny i tp.).


Vypusk 163. 01-19 iyulya 2007

obzor arxiv:0707.1279 K ponimaniyu obrazovaniya massivnyh zvezd (Toward Understanding Massive Star Formation)
Authors: Hans Zinnecker, Harold W. Yorke
Comments: 139 pages, 18 figures, 5 tables, glossary

Gigantskii obzor po obrazovaniyu massivnyh zvezd. Vklyucheno ochen' mnogo materiala.


obzor arxiv:0707.2166 Hromosfernaya dinamika i obrazovanie linii (Chromospheric Dynamics and Line Formation)
Authors: R. Hammer, P. Ulmschneider
Comments: 35 pages, Lecture notes and review, held at Kodaikanal Winter School on Solar Physics, Dec 2006. This version contains corrected page numbers for some of the references

V obzore rassmatrivaetsya fizika obrazovaniya linii v burlyashih verhnih sloyah Solnca.


arxiv:0707.2252 O bystrom kollapse i evolyucii molekulyarnyh oblakov (On the Rapid Collapse and Evolution of Molecular Clouds)
Authors: Bruce G. Elmegreen
Comments: 46 pages, 5 figures, scheduled for ApJ 668, October 20, 2007

Bol'shaya rabota, v kotoroi podrobno rassmatrivaetsya kollaps, privodyashii k poyavleniyu zvezd v gigantskih molekulyarnyh oblakah.


arxiv:0707.2652 Spektral'nyi atlas buryh karlikov (A high resolution spectral atlas of brown dwarfs)
Authors: A. Reiners, D. Homeier, P.H. Hauschildt, F. Allard
Comments: 17 pages, 11 figures, accepted by A&A

Po dannym VLT sostavlen spektral'nyi atlas vysokogo razresheniya dlya treh L i odnogo T karlika. Rezul'taty sravnivayutsya s modelyami. Chto-to oni opisyvayut horosho, a chto-to - ne ochen'.


Vypusk 161. 09-19 iyunya 2007

arxiv:0706.1646 Predely dlya opticheskoi astrometrii ul'travysokoi tochnosti: struktura zvezdnoi poverhnosti (Limits of ultra-high-precision optical astrometry: Stellar surface structures)
Authors: Urban Eriksson, Lennart Lindegren
Comments: 12 pages, 4 figures, submitted to A&A

Rassmatrivayutsya effekty, kotorye mogut ogranichit' tochnost' zvezdnoi astrometrii. Delo v tom, chto standartnym predpolozheniem yavlyaetsya to, chto poverhnost' zvezdy svetit ravnomerno, t.e. chto na nei net pyaten. Poka my ne dobiraemsya do ochen'-ochen' tochnyh izmerenii, eto predpolozhenie rabotaet. Esli zhe my hotim iskat' ekzoplanety tipa Zemli, to togda uzhe nado rassmatrivat' vozmozhnye problemy.

V stat'e rassmatrivaetsya, kak nalichie detalei na poverhnosti zvezdy mozhet ogranichivat' astrometricheskie metody poiska zemnopodobnyh planet v zonah obitaniya vokrug zvezd razlichnyh tipov.


Vypusk 160. 01-08 iyunya 2007

arxiv:0706.0500 Bolee glubokii poisk praroditelya sverhnovoi tipa Ic 2002ap (A deeper search for the progenitor of the Type Ic Supernova 2002ap)
Authors: R. M. Crockett, et al.
Comments: 20 pages, 11 figures (resolution of images reduced), 6 tables, submitted for publication in MNRAS

Izuchenie sverhnovyh vyshlo na novyi uroven', kogda stalo vozmozhnym iskat' zvezdy-praroditeli na arhivnyh snimkah. Pravda, primery, kogda praroditel' byl identificirovan, mozhno pereschitat' po pal'cam. V obsuzhdaemoi stat'e praroditel' ne naiden, no postavleny ochen' vazhnye verhnie predely, krome togo, rech' idet o sverhnovyh tipa Ic.

Verhnii predel govorit o tom, chto praroditelem mogla byt' tol'ko zvezda Vol'fa-Raie. Prichem, esli eto byla odinochnaya zvezda, to ona dolzhna byla by imet' ochen' bol'shoi temp poteri massy, bol'she standartnogo. Znachit, veroyatnee vsego, zvezda-praroditel' vhodila v dvoinuyu sistemu. Sootvetstvenno, mozhno posmotret' ne viden li seichas vtoroi komponent. Ne viden. Znachit, mozhno dat' ogranichenie na ego massu, esli eto normal'naya zvezda (razumeetsya, kompan'on mozhet byt' kompaktnym ob'ektom).
V obshem, na moi vzglyad, nablyudeniya nachinayut davat' ochen' vazhnye dlya modelei sverhnovyh dannye.


arxiv:0706.0867 Izobrazhenie poverhnosti Al'taira (Imaging the Surface of Altair)
Authors: John D. Monnnier et al.
Comments: 24 pages. to appear in Science. includes Report and Supplemental Online Materials. Accompanying animation can be found at this http URL

Vot i poyavilsya polnyi tekst raboty, o kotoroi tak mnogo pisali v SMI.

S pomosh'yu interferometra, rabotayushego v blizhnem IK diapazone, udalos' poluchit' neplohie izobrazheniya al'fa Orla. Uglovoe razreshenie luchshe odnoi tysyachnoi sekundy dugi (v itoge chto-to okolo odnoi desyatimillionnoi gradusa, ili, esli ugodno, odnoi milliardnoi dugi, nemnogo okruglyaya).

Razumeetsya, dlya ob'yasneniya bolee detal'nyh dannyh nuzhny i bolee detal'nye zvezdnye modeli. Teoretiki berutsya za rabotu.


arxiv:0706.0900 Ogranichenie na kiki belyh karlikov v sharovyh skopleniyah (Constraining white-dwarf kicks in globular clusters)
Authors: Jeremy S. Heyl
Comments: 4 pages, 3 figures, submitted to MNRAS Letters

Na stadii asimptoticheskoi vetvi gigantov zvezdnyi veter mozhet byt' sil'nym i sushestvenno asimmetrichnym. Itogo mozhet stat' razgon ostayushegosya zvezdnogo yadra - budushego belogo karlika. V nekotorom smysle mozhno skazat', chto kak i neitronnye zvezdy, belye karliki pri svoem rozhdenii poluchayut kik (kick - udar, tolchok). Konechno, sbros obolochki gigantom - eto ne vzryv sverhnovyh, poetomu kik u belyh karlikov ne mozhet dostigat' tysyach km/s, kak u neitronnyh zvezd. Tem ne menee, mogut byt' nablyudatel'nye effekty, svyazannye s raspredeleniem belyh karlikov v sharovyh skopleniyah. Vo-pervyh, chast' belyh karlikov mozhet prosto vyletat' iz skoplenii, t.e. budet nablyudat'sya ih deficit. Vo-vtoryh, molodye karliki (kotorye eshe ne uspeli vyletet') budut menee koncentrirovany k centru skopleniya. Poslednee - nablyudaetsya. T.o., polagaet Dzheremi Heil, raspredelenie molodyh belyh karlikov v sharovyh skopleniyah mozhet posluzhit' unikal'nym instrumentom dlya izucheniya poteri massy na asimptoticheskoi vetvi gigantov i vo vremya formirovaniya planetarnyh tumannostei.

Sm. takzhe arxiv:0706.0912. V etoi stat'e Heil rassmatrivaet vozdeistvie kika belyh karlikov na ih zhizn' v tesnoi dvoinoi sisteme.


Vypusk 159. 22-31 maya 2007

arxiv:0705.3668 Neobychno yarkii tranzient v gallaktike Mess'e 85 (An unusually brilliant transient in the galaxy Messier 85)
Authors: S. R. Kulkarni, et al.
Comments: 10 pages, 4 figures. Appeared in Nature May 24, vol. 447 (2007) pp. 458-460

V linzovidnoi galaktike M85 v skoplenii v Deve obnaruzhena neobychnaya vspyshka.

Sama vspyshka byla otkryta 7 yanvarya 2006 goda. Za dva mesyaca tranzient izluchil okolo 1047 erg (t.e. okolo 1040 dzhoulei), v maksimume svetimost' pochti v 10 millionov raz prevoshodila solnechnuyu. Na meste vspyshki na arhivnyh snimkah net nikakoi yarkoi zvezdy, t.e. vspyshku nel'zya otnesti k aktivnosti LBV zvezd (yarkih golubyh peremennyh) tipa Eta Kilya. S drugoi storony, opticheskii tranzient sushestvenno slabee samyh slabyh sverhnovyh, no sushestvenno yarche izvestnyh novyh. Avtory polagayut, chto prichinoi vspyshki moglo stat' sliyanie dvuh obychnyh zvezd. V proshlom dvazhdy fiksirovalis' pohozhie vspyshki (v tumannosti Andromedy i v nashei galaktike), no izuchit' ih podrobno ne udavalos'.

Sm. takzhe novost' na Granyah.


arxiv:0705.4195 VSOP: The Variable Star One-shot Project I. Opisanie proekta i pervyi reliz dannyh (VSOP: The Variable Star One-shot Project I. Project presentation and first data release)
Authors: T. H. Dall et al.
Comments: 16 pages, Accepted for publication in A&A

VSOP - The Variable Star One-shot Project. Zadacha proekta sostoit v avtomaticheskom obzore vseh peremennyh (izvestnyh i neizvestnyh). Dannye vykladyvayutsya v otkrytyi dostup. Proekt poka tol'ko nachal rabotat', poetomu rezul'tatov ne tak uzh mnogo.

Otmechu takzhe proekt Wikimbad, s kotorym svyazan VSOP. Eto otkrytaya baza dannyh astronomicheskih nablyudenii, v kotoroi kazhdyi mozhet pouchastvovat' ne tol'ko kak pol'zovatel', no i kak avtor.

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.


arxiv:0705.4274 Superyarkie sverhnovye: net ugrozy ot Eta Kilya (Superluminous supernovae: No threat from Eta Carinae)
Authors: Brian C. Thomas et al.
Comments: 12 pages, 2 figures

Otkrytie v proshlom godu ochen' moshnoi sverhnovoi 2006gy vyzvalo u nekotoryh lyudei opaseniya: a chto esli gde-to u nas pod bokom rvanet? Nekotorye avtory polagayut, chto izvestnaya ochen' massivnaya zvezda Eta Kilya mozhet v budushem privesti k takomu moshnomu vzryvu. Potencial'nye posledstviya takogo sobytiya rassmotreny v stat'e.

Kak i ozhidalos', vse mogut spat' spokoino. dazhe esli v kakom-to dalekom (sotni tysyach let) budushem Eta Kilya i rvanet kak 2006gy, to zhizni na Zemle eto ne ugrozhaet.


obzor arxiv:0705.4512 r-process v zvezdnom nukleosinteze: dostizheniya i zagadki v astrofizike i yadernoi fizike (The r-process of stellar nucleosynthesis: Astrophysics and nuclear physics achievements and mysteries)
Authors: M. Arnould, S. Goriely, K. Takahashi
Comments: 164 pages, 98 figures, accepted for publication in Phys. Rep.

Gigantskii obzor (prakticheski kniga) po t.n. r-processu v astrofizike.

r-process sostoit v zahvate neitrona. Proishodit on pri vysokoi plotnosti i temperature (vazhno, chtoby byla vysoka neitronnaya plotnost'). "r"- oboznachaet "rapid", t.e. "bystryi" (kak mozhno dogadat'sya, est' eshe i s-process). r-process protekaet, naprimer, pri kollapse zvezdnyh yader. Detal'nomu opisaniyu fiziki, svyazannoi so vsem etim, i posvyashen obzor.


Vypusk 158. 12-21 maya 2007

arxiv:0705.1592 Parallaksy cefeid i postoyannaya Habbla (Cepheid Parallaxes and the Hubble Constant)
Authors: Floor van Leeuwen et al.
Comments: 9 pages, 1 figure, on-line material from mwf@artemisia.ast.uct.ac.za. Accepted for MNRAS

Avtory ispol'zuyut peresmotrennye parallaksy cefeid, poluchennye s pomosh'yu sputnika Gipparkos. Ispol'zuya novye rezul'taty, oni peresmatrivayut rasstoyaniya do galaktik, ispol'zovavshihsya pri ocenke postoyannoi Habbla. V srednem ocenka postoyannoi vozrastaet primenrno na 10 procentov.


obzor arxiv:0705.1599 Sushestvuet li vselenskaya funkciya mass? (Is There a Universal Mass Function?)
Authors: Bruno Binggeli, Tatjana Hascher
Comments: 17 pages, 11 figures - Accepted for publication in PASP (review)

Dovol'no interesnyi obzor, ibo zatragivaet prakticheski vse izvestnye astronomicheskie ob'ekty. Konkretno, avtory rassmatrivayut funkcii mass ob'ektov ot melkih asteroidov do skoplenii galaktik. V ochen' shirokom predele grubo mozhno opisat' "vselenskuyu" funkciyu mass odnim stepennym pokazatelem okolo -2 (sm. ris. 10 na str. 12). Konechno, otkloneniya est', i zachastuyu oni ochen' veliki. No, povtoryus', na moi vzglyad interesen ne kakoi-to konechnyi vyvod o global'noi funkcii mass, a imenno obzor.

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.


arxiv:0705.2231 Zvezdnye mazery, okolozvezdnye obolochki i ostatki sverhnovyh (Stellar masers, circumstellar envelopes, and supernova remnants)
Authors: Athol J. Kemball
Comments: 16 pages, 2 figures, 2 tables: based on a review talk presented at IAU Symposium 242: Astrophysical masers and their environments, held at Alice Springs (Australia), March 12-16, 2007

Na moi vzglyad, tema zvezdnyh mazerov yavlyaetsya slegka "nedopopulyarizirovannoi". Pravda, dannyi obzor tut ne ochen' bol'shaya podmoga, ibo napisan on dlya teh, kto vsyu osnovu i tak uzhe znaet - t.e. dlya specialistov.


Vypusk 157. 01-11 maya 2007

arxiv:0705.0605 TYC 1031 012262 1: Pervaya galakticheskaya zatmennaya dvoinaya s cefeidoi tipa II (TYC 1031 01262 1: The First Known Galactic Eclipsing Binary with a Type II Cepheid Component)
Authors: S.V. Antipin, K.V. Sokolovsky, T.I. Ignatieva
Comments: 3 pages, 3 figures, accepted to MNRAS Letters

Interesnoe otkrytie sdelali kollegi po GAISh.

Mnogie parametry zvezd mozhno kak sleduet izuchit' tol'ko v dvoinyh sistemah s zatmeniyami. Vo-pervyh, dvoistvennost' daet vozmozhnost' ocenit' massy zvezd. Vo-vtoryh, v sluchae zatmenii my tochno znaem orientaciyu orbity, a eto pozvolyaet uzhe poluchit' TOChNYE znacheniya mass. Nakonec, v-tret'ih, vo vremya zatmenii mozhno nadeyat'sya postroit' "kartu" zvezdy i opredelit' ee radius. Konechno, "karta" budet ochen' priblizhennoi, tem ne menee, eto daet vazhnuyu informaciyu o svoistvah zvezd.

Kak izvestno, sredi peremennyh zvezd vydelyayutsya cefeidy - pul'siruyushie peremennye. Vydelyayut cefeidy tipa I i II. Pervye svyazany so zvezdami naseleniya I - eto molodye ob'ekty. Cefeidy tipa II - eto zvezdy bolee starogo naseleniya II. O cefeidah tipa II mozhno prochest' zdes' http://www.geocities.com/theperiodictable/CepheidII/cepheidII.html.

Chrezvychaino vazhno otkryvat' cefeidy v zatmennyh dvoinyh. Eto pozvolyaet poluchit' tochnuyu informaciyu o svoistvah etih "mayakov vselennoi". Do opisyvaemogo otkrytiya v Galaktike bylo izvestno tri cefeidy tipa II v dvoinyh sistemah, no vse oni byli ne zatmennymi. Zatmennye byli izvestny tol'ko v Bol'shom magellanovom oblake (ih otkryli pri poiske sobytii mikrolinzirovaniya). I vot - pervaya zatmennaya cefeida tipa II v nashei Galaktike otkryta!

Peremennost' zvezdy TYC 1031 01262 1 obnaruzhili neskol'ko let nazad nezavisimo v obzore ASAS-3 i po arhivnyh dannym v GAISh. S 2004 goda v Krymskoi laboratorii GAISh na 50-santimetrovom teleskope s PZS-priemnikom provodili nablyudeniya etogo ob'ekta. V hode etih issledovanii i udalos' pokazat', chto vo-pervyh, my imeem delo s cefeidoi tipa II, a vo-vtoryh, chto zvezda vhodit v zatmennuyu dvoinuyu.

Period pul'sacii otkrytoi cefeidy sostavlyaet chut' bolee 4 dnei. A orbital'nyi period dvoinoi - chut' bolee 50 dnei. Eto rekordno korotkii period dlya dvoinyh cefeid (cefeidy - zvezdy krupnye, i v ochen' tesnuyu sistemu oni prosto ne pomeshyayutsya).

Izuchenie novoi dvoinoi sistemy mozhet prinesti vazhnuyu informaciyu o svoistvah nemolodyh zvezd. Naprimer, pul'sacii cefeid v dvoinyh dolzhny ispytyvat' vliyanie prilivnyh sil, svyazannyh s nalichiem zvezdy-sosedki. Da i prosto, kto znaet, kakie syurprizy eshe zhdut issledovatelei!

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.


obzor arxiv:0705.1376 Nablyudeniya oscillyacii solnechnogo tipa (Observations of solar-like oscillations)
Authors: Timothy R. Bedding, Hans Kjeldsen
Comments: Invited review talk at the "Vienna Workshop on the Future of Asteroseismology", 20-22 September 2006, to appear in Communications in Asteroseismology

Obzor po zvezdnoi seismologii. Na samom dele, rech' idet ne tol'ko o zvezdah tipa Solnca, kak napisano v zaglavii. Avtory takzhe rassmatrivayut dannye po kolebaniyah gigantov i sverhgigantov.


Vypusk 156. 24-30 aprelya 2007

arxiv:0704.3059 Poisk analogov Solnechnoi sistemy s pomosh'yu SIM i Hipparcos (Finding Solar System Analogs With SIM and HIPPARCOS: A White Paper for the ExoPlanet Task Force)
Authors: Rob P. Olling
Comments: A White Paper for the ExoPlanet Task Force: 7 pages

Ideya avtora sostoit v tom, chtoby ispol'zovat' dannye budushego sputnika SIM i uzhe otletavshego sputnika Hipparcos dlya poiska massivnyh planet i korichnevyh karlikov na shirokih orbitah.

Pri orbital'nom periode v desyatki i sotni let ochen' trudno rasschityvat' na kakoi-to rezul'tat za vremya zhizni sputnika (3-7 let). Odnako dannye s dvuh astrometricheskih sputnikov, otrabotavshih s intervalom let v dvadcat', uzhe mogut dat' neobhodimuyu tochnost'. Ocenki pokazyvayut, chto sovmestnaya obrabotka dannyh dvuh apparatov pozvolit obnaruzhit' planetu s massoi kak u Yupitera dazhe dlya orbital'nyh periodov v 240 let. A pri masse v dest' raz bol'she - 500 let.


miniobzor arxiv:0704.3171 Proishozhdenie rentgenovskogo izlucheniya zvezd T Tel'ca (The origin of X-ray emission from T Tauri stars)
Authors: Thomas Preibisch
Comments: 8 pages, Review talk at the Conference "Coronae of Stars and Accretion Disks", Bonn, Germany, December 2006. Conference proceedings to be published in Memorie della Societa Astronomica Italiana

Zvezdy tipa T Tel'ca - eto molodye ob'ekty, eshe nahodyashie na stadii formirovaniya. Oni izvestny kak istochniki rentgenovskogo izlucheniya. Nedavnie usiliya po nablyudeniyam etih istochnikov na Chandre priveli k luchshemu ponimaniyu processov, privodyashih k izlucheniyu. Odnako polnoi yasnosti net. Vsemu etomu i posvyashen obzor.

Osnovnye vyvody avtora takovy:
1. Vse zvezdy T Tel'ca proyavlyayut povyshennuyu aktivnost' a rentgene (vne zavisimosti ot massy)
2. Osnovnaya dolya rentgenovskogo izlucheniya svyazana s koronal'noi aktivnost'yu
3. Dolya, za kotoruyu otvetstvenna akkreciya, mala.


Vypusk 155. 13-23 aprelya 2007

arxiv:0704.1813 Otkrytie kompan'ona u samogo legkogo belogo karlika (The Discovery of a Companion to the Lowest Mass White Dwarf)
Authors: Mukremin Kilic et al.
Comments: 16 pages, ApJ, in press.

Samyi legkii (0.17 mass Solnca) belyi karlik SDSS J091709.55+463821.8 okazalsya dvoinym. Izmerenie radial'noi skorosti karlika pokazalo, chto est' bolee massivnyi kompan'on. Poskol'ku kompan'ona ne vidno, to eto dolzhen byt' drugoi kompaktnyi ob'ekt. Skoree vsego vtoroi belyi karlik, no poka, pishut avtory, nel'zya isklyuchit' i neitronnuyu zvezdu.

Ot sebya dobavlyu, chto i chernuyu dyru isklyuchit' nel'zya, hotya veroyatnost' ee nalichiya tam - ne bolee neskol'kih procentov.


arxiv:0704.2415 Nablyudeniya v blizhnem IK i v rentgene zagadochnogo G70.7+1.2 (Near-Infrared and X-ray Observations of the Enigmatic G70.7+1.2)
Authors: P. B. Cameron, S. R. Kulkarni
Comments: 13 pages, 4 figures. Submitted to ApJL, referee's comments incorporated

Priroda poroyu podkidyvaet interesnye zagadki. Nichego superfundamental'nogo v nih net, no mne lichno oin vsegda nravyatsya. Sut' zagadki svoditsya k sleduyushemu: chto zhe my vidim?

G70.7+1.2 - eto tumannost', nablyudaemaya v opticheskom i radio diapazonah. Krome togo, v nei est' yarkaya zvezda, kotoruyu nablyudayut v IK, t.k. veliko pogloshenie. Polagali, chto my imeem delo s dvoinoi sistemoi, sostoyashei iz Be- zvezdy i radiopul'sara.

Avtory stat'i proveli glubokie nablyudeniya v IK (na Keke) i v rentgene (na Chandre). Byl obnaruzhen rentgenovskii istochnik, ne sovpadayushii s Be-zvezdoi. Tot zhe istochnik viden i v blizhnem IK. Novaya interpretaciya takova. V tumannosti est' Be-zvezda i dvoinaya sistema, sostoyashaya iz B-zvezdy i neitronnoi zvezdy, skoree vsego radiopul'sara. Sleduyushaya zadacha - glubokii poisk pul'sara. Esli ne naidut - to zagadka ostanetsya. Interesno!


Vypusk 154. 01-12 aprelya 2007

obzor arxiv:0704.0770 Himicheskaya evolyuciya (Chemical Evolution)
Authors: Francesca Matteucci
Comments: 56 pages, Lectures delivered at the XVIII Canarie Winter School on "Emission Lines Universe"

Ochen' detal'naya lekciya po himicheskoi evolyucii. Termin "himicheskaya evolyuciya" primenim, razumeetsya, v pervuyu ochered' ili k mezhzvezdnoi, ili k mezhgalakticheskoi srede. Vse eto v obzore est'. Est' tam eshe i opisanie razlichnyh processov, opredelyayushih etu evolyuciya. T.o., avtoru prihoditsya govorit' edva li ne o polovine vsei astrofiziki!


miniobzor arxiv:0704.1215 Dvoinye neitronnye zvezdy: ukazanie na dva razlichnyh mehanizma obrazovaniya (Double Neutron Stars: Evidence For Two Different Neutron-Star Formation Mechanisms)
Authors: E.P.J. van den Heuvel
Comments: 9 pages. Invited talk at he Multicoloured Landscape of Compact Objects and their Explosive Origins', Cefalu', 2006 June 11-24 (AIP Conf. Proc.), eds. L. Burderi et al., i

Izvestno 9 dvoinyh sistem, sostoyashih iz dvuh neitronnyh zvezd. S nimi svyazana odna zagadka. Slishkom mnogie iz nih imeyut malen'kie ekscentrisitety. Esli uchest', chto soglasno dannym po obychnym radiopul'saram neitronnye zvezdy rozhdayutsya s bol'shimi skorostyami (t.n. kik) poryadka 300-400 km/s, to malye ekscentrisitety predstavlyayutsya zagadochnymi. Po vsei vidimostim, te vzryvy sverhnovyh, kotorye privodyat (v srednem) k poyavleniyu odinochnyh pul'sarov i pul'sarov v massivnyh dvoinyh sistemah, razlichayutsya. Van den Hevel obsuzhdaet vozmozhnye puti resheniya zagadki. Na dannyi moment slozhilsya sleduyushii vzglyad. Vtorichnye komponenty massivnyh dvoinyh sistem ispytyvayut ne obychnyi vzryv sverhnovoi, svyazannyi s kollapsom zheleznogo yadra, a kollaps kislorodno-neonovo-magnievogo yadra. Veroyatnee vsego, eto yavlyaets isklyuchitel'noi osobennost'yu dvoinyh sistem. V odinochnyh zvezdah takie yadra v konce koncov prevrashayutsya v belye karliki.


Vypusk 153. 20-31 marta 2007

astro-ph/0703516 Vozmozhnyi cikl aktivnosti u Proksima Centavra (A possible activity cycle in Proxima Centauri)
Authors: Carolina Cincunegui, Rodrigo F. Daz, Pablo J. D. Mauas
Comments: 7 pages, including 8 figures and 2 tables, Astronomy & Astrophysics, Volume 461, Issue 3, January III 2007, pp.1107-1113

Periodicheskaya aktivnost', tipa solnechnogo 11-letnego cikla, izvestna u mnogih zvezd spektral'nyh klassov ot F do K. Avtory popytalis' naiti nechto podobnoe u Proksimy Centavra. Eto malen'kaya zvezdochka klassa dM5.5e. Vozmozhno, chto takoi cikl taki otkryt. Period ego sostavlyaet 442 dnya.

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.


miniobzor astro-ph/0703655 Vvedenie v zvezdnuyu koronografiyu (Introduction to stellar coronagraphy)
Authors: A. Ferrari, R. Soummer, C. Aime
Comments: 11 pages

Zamechatel'nyi obzor po zvezdnoi koronografii. Nachinaetsya vse s ponyatnogo ob'yasneniya osnov, no potom dayutsya i neobhodimye detali.


katalog astro-ph/0703658 Novyi reliz biblioteki ELODIE: versiya 3.1 (New release of the ELODIE library: Version 3.1)
Authors: Ph. Prugniel et al.
Comments: 8 pages

Predstavlen novyi reliz biblioteki zvezdnyh spektrov ELODIE. Biblioteka soderzhit pochti 2000 spektrov zvezd.

Sama biblioteka dostupna zdes'.


obzor astro-ph/0703724 Struktura i evolyuciya malomassivnyh zvezd: obzor i otkrytye problemy (Structure and Evolution of Low-Mass Stars: An Overview and Some Open Problems)
Authors: M. Catelan
Comments: 52 pages, 6 figures. Invited review, to appear in "XIth Special Courses at the National Observatory of Rio de Janeiro" (AIP Conf. Proc.), ed. J. Alcaniz, R. de la Reza, F. Roig, & D. F. Lopes

Kak izvestno, evolyuciya massivnyh i malomassivnyh zvezd protekaet po-raznomu. V dannom obzore zhiznennyi put' malomassivnoi zvezdy rassmatrivaetsya ot nachala do konca - ot zarozhdeniya zvezdy v oblake do ostyvayushego belogo karlika.


Vypusk 152. 10-19 marta 2007

astro-ph/0703317 Troinoe kol'co vokrug SN 1987A: otpechatok sliyaniya dvoinoi (The Triple-Ring Nebula around SN1987A: Fingerprint of a binary merger)
Authors: T. Morris, Ph. Podsiadlowski
Comments: 6 pages (including 7 pages of supplementary material), 2 figures (reduced in size), appeared in Science on 23rd February 2007. Science 315 (2007) 1103-1106

Avtory pokazyvayut s pomosh'yu trehmernogo modelirovaniya, chto sistema troinyh kolec vokrug SN1987A mogla poyavit'sya iz-za togo, chto praroditelem byla zvezda, obrazovavshayasya v rezul'tate sliyaniya komponent dvoinoi sistemy.

Animacii dostupny zdes' i zdes'.

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.


astro-ph/0703414 Otkrytie HE 1523-0901, zvezdy s maloi metallichnost'yu, sil'no obogashennoi r-processom, s zaregistrirovannym uranom (Discovery of HE 1523-0901, a Strongly r-Process Enhanced Metal-Poor Star with Detected Uranium)
Authors: Anna Frebel et al.
Comments: 7 pages, 2 figures. Accepted for publication in ApJ Letters

Sobstvenno, koryavye perevod zagolovka uzhe soderzhit v sebe vsyu osnovnuyu infrmaciyu. Obnaruzhena zvezda s maloi metallichnost'yu. Vazhnoi osobennost'yu yavlyayutsya ee himicheskie anomalii. Spektr pokazyvaet, chto zvezda sil'no obogashena elementami, obrazuyushimisya v t.n. r-processe. Etot process ne idet sobstvenno v zvezdah na stadii termoyadernogo goreniya. Neobhodimo, chtoby vzryvalas' sverhnovaya, ili proishodilo eshe chto-nibud' interesnoe. Sredi drugie netipichnyh dlya zvezd elementov, obnaruzhen uran. Prichem linii urana v spektre dostatochno sil'ny. Nalichie sil'nyh linii neskol'kih redkih elementov pozvolilo tochno opredelit' voshrast zvezdy. On okazalsya ravnym 13.2 milliarda let.


Vypusk 151. 01-09 marta 2007

astro-ph/0703005 Katalog galakticheskih O-zvezd V.2.0 (The Galactic O Star Catalog V.2.0)
Authors: A. Sota, J. Maz Apellniz, Nolan R. Walborn, R. Y. Shida
Comments: 1 page, to appear in Massive Stars: Fundamental Parameters and Circumstellar Interactions

Vsego odna stranichka, no ochen' poleznaya.

Avtory opisyvayut katalog O-zvezd. Osnovnoi katalog soderdit 378 zvezd. Vo vtoroi versii predstavleny dopolneniya, vklyuchayushie 700 zvezd, kotorye mogut byt' klassificirovanny, kak prinadlezhashie k spektral'nomu klassu O. Krome togo, dobavlen spisok O-zvezd v tesnyh (nerazreshennyh) parah so zvezdami Vol'fa-Raie, a takzhe spisok V-zvezd, kotorye kogda-to vklyuchalis' v katalogi O-zvezd.

Sam katalog dostupen po adresu http://www-int.stsci.edu/~jmaiz/GOS/GOSmain.html.


obzor astro-ph/0703124 Nachal'naya funkciya mass prostyh i sostavnyh zvezdnyh populyacii (The initial mass function of simple and composite stellar populations)
Authors: Pavel Kroupa
Comments: 70 pages, 23 figures, 3 tables, in Proceedings of the Meeting "Resolved Stellar Populations", Cancun, Mexico, 18-22 April 2005, eds. D. Valls-Gabaud and M. Chavez, ASP Conf. Ser. (in press). This version is slightly modified in having additional clarifications and a few newer references than the proceedings version

Bol'shoi obzor po nachal'noi funkcii mass zvezd.


Vypusk 150. 15-28 fevralya 2007

astro-ph/0702410 Vliyanie magnitnogo polya na formirovanie odinochnyh i dvoinyh zvezd (The impact of magnetic fields on single and binary star formation)
Authors: Daniel J. Price, Matthew R. Bate
Comments: 15 pages, 12 figures, accepted for publication in MNRAS.

Avtory chislenno modelirovali process zvezdoobrazovaniya s uchetom vliyaniya magnitnyh polei. Rezul'taty raschetov neskol'ko otlichayutsya ot osnovnoi massy analogichnyh rabot, prodelannyh ranee. Rol' magnitnyh polei, po raschetam avtorov, okazyvaetsya ochen' velika. Magnitnoe davlenie sushestvenno prepyatstvuet fragmentacii molekulyarnogo oblaka. V chastnosti, sil'nye polya mogut prepyatstvovat' formirovaniyu tesnyh dvoinyh zvezdnyh sistem, a takzhe planetnyh sistem. Zato mogut obrazovyvat'sya shirokie dvoinye zvezdy (te. sistemy s bol'shim or'ital'nym periodom).


astro-ph/0702647 Otkrytie samoi shirokoi ochen' malomassivnoi dvoinoi (Discovery of the Widest Very Low Mass Binary)
Authors: Etienne Artigau et al.
Comments: accepted ApJL, 4 pages

Ochen' malomassivnye sistemy - eto zvezdnye pary, v kotoryh massa bolee massivnogo komponenta ne prevoshodit 0.1 solnechnoi. Obnaruzhena dvoinaya etogo tipa, v kotoroi rasstoyanie mezhdu komponentami sostavlyaet bolee 5000 a.e. Eto ne prosto rekord. Orbita novoi dvoinoi v dva s lishnim raza shire, chem u perdydushei rekordsmenki. Paru sostavlyayut zvezdy klassov M6.5V i M8V. Rasstoyanie do sistemy - 62 parseka.

Otkrytie takoi zvezdnoi pary stavit nekotorye voprosy pered teoriyami obrazovaniya i evolyucii dvoinyh.


Vypusk 149. 01-14 fevralya 2007

astro-ph/0702248 Poisk periodov massivnyh rentgenovskih dvoinyh (Finding Periods in High Mass X-Ray Binaries)
Authors: Gordon E. Sarty, Laszlo L. Kiss, Helen M. Johnston, Richard Huziak, Kinwah Wu
Comments: 11 pages, Accepted: JAAVSO

Stat'ya yavlyaetsya prizyvom k astronomam-lyubitelyam zanyat'sya poiskom i izucheniem periodichnosti v opticheskih krivyh bleska massivnyh rentgenovskih sistem.

V stat'e rasskazyvaetsya chto eto za sistemy, kak i zachem ih nuzhno nablyudat'.

Dobavlyu, chto katalog sistem s Ve-zvezdami mozhno naiti zdes'.

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.



astro-ph/0702296 Oskolochnyi disk vokrug central'noi zvezdy tumannosti "Ulitka" (A Debris Disk around the Central Star of the Helix Nebula?)
Authors: Kate Y. L. Su et al.
Comments: 5 pages, emulateapj format, accepted for publication in ApJ Letters

S pomosh'yu kosmicheskoi infrakrasnoi observatorii Spitcer udalos' uvidet' disk vokrug central'noi zvezdy izvestnoi planetarnoi tumannosti "Ulitka" (NGC 7293). Central'noi zvezdoi yavlyaetsya goryachii (110 000K) belyi karlik. Sushestvuyut zhestkie ogranicheniya na vozmozhnuyu dvoistvennost' zvezdy.


Na risunke pokazano izobrazhenie tumannosti "Ulitka" na dline volny 70 mikron.

Avtory polagayut, chto nalichie diska mozhet byt' svyazano so stolknoveniyami ob'ektov, vhodyashih v strukturu tipa nashego poyasa Koipera, ili s ispareniem komet, vhodyashih v analog oblaka Oorta. Eto bylo by dovol'no lyubopytno, t.k. zvezda, ochevidno, proshla stadiyu giganta i sbrosila obolochku. Znachit, ili komety, ili planetoidy smogli etot epizod v zhizni zvezdy perezhit'.


Vypusk 148. 13-31 yanvarya 2007

astro-ph/0701488 Pervaya pryamaya registraciya gravitacionnoi mikrolinzy v napravlenii galakticheskogo baldzha (The first direct detection of a gravitational microlens toward the Galactic bulge)
Authors: S. Kozlowski et al.
Comments: 6 pages, 5 figures; submitted to ApJ

Obychno, kogda nablyudayut effekt mikrolinzirovaniya, to ob'ekt-linza ostaetsya neizvestnym. Chto-to temnoe i massivnoe proletelo mezhdu nami i istochnikom - i vse. Redko-redko udaetsya potom rassmotret' samu linzu. Vot vpervye razglyadeli zvezdochku, vyzvavshuyu sobytie MACHO-95-BLG-37. Ei okazalas' zvezda tipa Solnca (chut' men'she i holodnee, spektral'nyi klass K2) s massoi okolo 0.6 solnechnyh na rasstoyanii 3.5 kpk ot nas.


obzor astro-ph/0701654 Kataklizmicheskie peremennye (Cataclysmic Variables)
Authors: Robert Connon Smith
Comments: 41 pages, 11 figures, invited review for Contemporary Physics

Podrobnyi obzor po kataklizmicheskim peremennym. Eto ochen' interesnye tesnye dvoinye sistemy s belymi karlikami, pokazyvayushie bol'shoe raznoobrazie astrofizicheskih yavlenii.


miniobzor astro-ph/0701740 Rezyume po potere massy - sub'ektivnyi vzglyad (Mass loss summary - a personal perspective)
Authors: Jorick S. Vink
Comments: 5 pages, Conference summary on stellar winds to appear in "Mass loss from stars and the evolution of stellar clusters". Proc. of a workshop held in honour of H.J.G.L.M. Lamers, Lunteren, The Netherlands. Eds. A. de Koter, L. Smith and R. Waters (San Francisco: ASP)

Est' takoi izvestnyi astrofizik - Lamers. V ego chest' byla provedena rabochaya vstrecha, posvyashennaya ego kon'ku - potere massy massivnymi zvezdami.

V korotkom obzore summirovany osnovnye poslednie razrabotki i dostizheniya v dannoi oblasti.


Vypusk 147. 22 dekabrya 2006-12 yanvarya 2007

astro-ph/0612697 Gazovyi metallicheskii disk vokrug belogo karlika (A gaseous metal disk around a white dwarf)
Authors: B.T. Gansicke et al.
Comments: 16 pages, Published 22 December in Science

Vokrug belogo karlika obnaruzhen gazovyi disk s bol'shim soderzhaniem metallov. Avtory polagayut, chto disk byl obrazovan v rezul'tate prilivnogo razrusheniya asteroida.

Razumeetsya, asteroid ne mog perezhit' na orbite razrusheniya stadiyu krasnogo giganta. Sootvetstvenno, on dolzhen byl migrirovat' s rasstoyaniya v tysyachu radiusov Solnca v rezul'tate vozmusheniya kakim-to drugim telom, takzhe vrashayushimsya vokrug belogo karlika. Vazhno, chto otkrytie govorit o tom, chto planetnye sistemy uspevayut sformirovat'sya vokrug dostatochno massivnyh i korotkozhivushih zvezd. O malom vremeni zhizni zvezdy (i o ee otnositel'no vysokoi masse) svidetel'stvuet massa belogo karlika.


astro-ph/0701059 Evolyuciya tesnyh dvoinyh sistem (The Evolution of Compact Binary Star Systems)
Authors: Konstantin Postnov, Lev Yungelson
Comments: 105 pages, 18 figures, Living Reviews in Relativity, Lrr-2006-6

Bol'shoi obzor po evolyucii tesnyh dvoinyh sistem. Stat'ya takzhe dostupna zdes'.


astro-ph/0701214 CU Virginis - Pervaya zvezda-pul'sar (CU Virginis - The First Stellar Pulsar)
Authors: Barry J. Kellett et al.
Comments: 10 pages including 2 figures

Zvezda CU Vir uzhe byla izvestna kak radioistochnik. Ona otnositsya k klassu zamagnichennyh zvezd s himicheskimi osobennostyami, tak chto v fakte radioizlucheniya net nichego super strannogo. Odnako avtoram rassmatrivaemoi stat'i udalos' obnaruzhit' interesnoe svoistvo: zvezda izluchaet postoyannyi horosho kollimirovannyi puchok stoprocentno polyarizovannogo radioizlucheniya. T.e., rabotaet primerno kak radiopul'sar! Takzhe kak u pul'sarov period vrasheniya zvezdy postoyanno zamedlyaetsya.

Cu Vir byla obnaruzhena kak zvezda s peremennym spektrom v 1952 godu, a v 1994 bylo otkryto radioizluchenie etogo ob'ekta. Eto odin iz samyi moshnyh radioistochnikov sredi zamagnichennyh zvezd s himicheskimi anomaliyami. Period vrasheniya sostavlyaet primerno poldnya. Rasstoyanie do zvezdy vsego 80 pk. Pole na poverhnosti sostavlyaet neskol'ko tysyach gauss (dlya sravneniya, na Solnce - okolo odnogo gaussa).

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.



astro-ph/0701310 Chernaya dyra v sharovom skoplenii (A black hole in a globular cluster)
Authors: Thomas J. Maccarone et al.
Comments: 11 pages, 1 figure, to appear in 11 January edition of Nature.

Rentgenovskie nablyudeniya ukazyvayut na nalichie v sharovom skoplenii v galaktike NGC 4472 akkreciruyushei chernoi dyry. Sobstvenno, ukazanie sostoit v tom, chto svetimost' istochnika slishkom vysoka, chtoby ob'yasnit' ee akkreciei na neitronnuyu zvezdu, a peremennost' istochnika isklyuchaet vozmozhnost' togo, chto svetyat neskol'ko otdel'nyh ob'ektov, slivayushihsya dlya nas v odin.


astro-ph/0701334 Evolyuciya ochen' massivnyh zvezd (The evolution of very massive stars)
Authors: H. Belkus, J. Van Bever, D. Vanbeveren
Comments: 16 pages, 4 figures, 2 tables. Accepted by ApJ

Avtory obsuzhdayut evolyuciyu zvezd s massami ot 300 do 1000 mass Solnca dlya raznyh metallichnostei. Takie zvezdy mogut poyavlyat'sya v plotnyh molodyh skopleniyah, naprimer v central'nyh oblastyah galaktik (v tom chisle i nashei). Raschety, vypolnennye v dannoi stat'e, osnovany na modeli stroeniya massivnyh zvezd, postroennoi Nadezhinym i Razinkovoi.

V sluchae solnechnoi metallichnosti massivnye zvezdy porozhdayut chernye dyry s massami do 75 solnechnyh. Pri ochen' maloi metallichnosti massa chernyh dyr vozrastaet v 2-3 raza. V promezhutochnom sluchae (metallichnost' men'she solnechnoi v neskol'ko raz) vozmozhen vzryv sverhnovoi bez obrazovaniya ostatka.



Vypusk 146. 01-21 dekabrya 2006

astro-ph/0612012 Pismis 24-1: Verhnii predel na zvezdnuyu massu ustoyal (Pismis 24-1: The Stellar Upper Mass Limit Preserved)
Authors: J. Maiz Apellaniz et al.
Comments: 15 pages, 3 figures, submitted to ApJ

Yarchaishii chlen skopleniya Pismis 24 byl zapodozren v tom, chto eto samaya massivnaya zvezda, ch'ya massa prevyshaet "psihologicheskii rubezh" v 150 solnechnyh mass. Detal'nye nablyudeniya na KTH pokazali, chto, kak uzhe ne raz byvalo, yarkii ob'ekt yavlyaetsya kratnoi sistemoi, i massa naibol'shei iz zvezd ne prevoshodit ustoyavshiisya predel.

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.


astro-ph/0612220 Buryi karlik - donor v dvoinoi sisteme s akkreciei (A brown dwarf mass donor in an accreting binary)
Authors: S.P. Littlefair et al.
Comments: 10 pages, 2 figures. This is the author's version of the work. It is posted here by permission of the AAAS for personal use, not for redistribution. The definitive version was published in SCIENCE, Vol #5805, 8-12-06

Pohozhe, chto vpervye obnaruzhena akkreciruyushaya dvoinaya sistema, v kotoroi donorom yavlyaetsya buryi (korichnevyi) karlik. Rech' idet o kataklizmicheskoi peremennoi SDSS 103533.03_055158.4, otkrytoi v opticheskom diapazone s pomosh'yu Sloanovskogo cifrovogo obzora neba. Orbital'nyi period sostavlyaet chut' bolee chasa (82 minuty). Akkreciya idet na belyi karlik. Massa donora ocenivaetsya primerno v 0.05 solnechnyh mass.

Obsudit' v ZhZh-soobshestve ru_astroph.
Obsudit' na Astroforume v Nauchnoi panorame.



Vypusk 145. 11-30 noyabrya 2006

astro-ph/0611498 Samyi legkii belyi karlik (The Lowest Mass White Dwarf)
Authors: Mukremin Kilic et al.
Comments: ApJ, submitted

"Samyi malen'kii gnom".

Imeya massu vsego lish' 0.17 solnechnyh, belyi karlik SDSS J0917+46 yavlyaetsya samym legkim iz vseh izvestnyh.


obzor astro-ph/0611589 Kakie zvezdy prevrashayutsya v chernye dyry, a kakie v neitronnye zvezdy? (Which Stars Form Black Holes and Neutron Stars?)
Authors: Michael P. Muno
Comments: 8 pages, 3 figures. Uses aipproc.cls. To appear in the proceedings of the conference ``The Multicoloured Landscape of Compact Objects and their Explosive Origins'', 2006 June 11--24, Cefalu, Sicily, to be published by AIP

Mne stat'ya pokazalas' ochen' interesnoi. V samom dele, my ploho ponimaem, kakie iz massivnyh zvezd prevrashayutsya v neitronnye zvezdy, a kakie v chernye dyry. Yasno tol'ko, chto net kakogo-to odnogo universal'nogo predela na massu, vyshe kotoroi zvezda yavlyaetsya praroditelem chernoi dyry.


Vypusk 143. 18-31 oktyabrya 2006

miniobzor astro-ph/0610558 Dvoinye zvezdy v planetarnyh tumannostyah (Binary central stars of planetary nebulae)
Authors: Albert A. Zijlstra
Comments: 8 pages, Invited review, in 'Evolution and chemistry of symbiotic stars and related objects', Wierzba, August 2006. To appear in Baltic Astronomy

Nebol'shoi, no ochen' emkii obzor. Kak chitatel' pomnit, ya ne raz rasskazyval o probleme formy planetarnyh tumannostei. O roli dvoistvennosti zvezd i o roli magnitnyh polei v etom voprose. Vse, chto kasaetsya dvoistvennosti summirovano v dannom obzore.

Dvoistvennost' mozhet vliyat' na formu tumannosti troyakim obrazom. Vo-pervyh, mozhet imet' mesto stadiya obshei obolochki. V etom sluchae nalichie kompan'ona privodit k ochen' sushestvennoi i bystroi poteri massy. Esli sistema bolee shirokaya, to kompan'on mozhet ne vliyat' na temp sbrosa veshestva, zato povliyaet na formu tumannosti. Nakonec, v sluchae samyh shirokih sistem iz-za smesheniya centra mass forma tumannosti takzhe okazhetsya ne takoi, kak u odinochnyh zvezd.

Yasno, chto dvoistvennost' vliyaet na formu planetarnoi tumannosti. No interesno, chto ostaetsya mnogo nereshennyh problem. Tak, naprimer, dlya mnogih tumannostei s ves'ma ekzoticheskoi formoi poka ne udaetsya poluchit' kakie-to dannyh o dvoistvennosti zvezd, ih porodivshih.


miniobzor astro-ph/0610676 Galakticheskaya istoriya: obrazovanie i evolyuciya (Galactic History: Formation and Evolution)
Authors: Joss Bland-Hawthorn, Ken Freeman
Comments: Invited Talk, 8 pages, 1 figure, Joint Discussion 13, IAU General Assembly XXVI, Prague

Stat'ya posvyashena zvezdnym obzoram. V nih soderzhitsya informaciya o cvetah, skorostyah i drugih parametrah millionov zvezd. Eto pozvolyaet "po zvezdam" chitat' istoriyu nashei Galaktiki. Naprimer, v etom godu ya ne raz pisal o rabotah, po vyyavleniyu novyh zvezdnyh potokov, svyazannyh s poglosheniem Galaktikoi kakogo-nibud' sputnika, ili o novyh sputnikah Mlechnogo puti. Vse eti raboty osnovyvayutsya na ogromnyh massivah dannyh (naprimer, na Sloanovskom cifrovom obzore neba). Poetomu "nudnaya" rabota po sostavleniyu katalogov i t.p. nabrov dannyh ochen' vazhna, k tomu zhe v 21 veke ona sovsem ne takaya skuchnaya kak v 19-m!


miniobzor astro-ph/0610826 Posledovatel'noe inducirovannoe zvezdoobrazovanie v OV associaciyah (Sequentially Triggered Star Formation in OB Associations)
Authors: Thomas Preibisch, Hans Zinnecker
Comments: 6 pages, Invited talk at the IAU Symposium 237: "Triggered Star Formation in a Turbulent ISM", Prague, Czech Republic, August 2006

Na primere blizhaishei OV associacii Skorpion-Centavr avtory rassmatrivayut triggernoe zvezdoobrazovanie.

Associaciya Skorpion-Centavr nahoditsya na rasstoyanii primerno 150 pk ot nas. Ona delitsya na tri chasti: Upper Scorpius (USco), Upper Centaurus-Lupus (UCL), Lower Centaurus-Crux (LCC). Pervaya iz nih imeet vozrast okolo 5 millionov let, vtoraya - okolo 17 millionov, i tret'ya - 16. Pohozhe, chto poyavlenie USco bylo inducirovano vspyshkami sverhnovyh v UCL (potom, poyavlenie massivnyh zvezd v USco, v svoyu ochered', okazalo vliyanie na zvezdoobrazovanie v drugih blizkih regionah). Interesno, chto novye dannye po molekulyarnym oblakam pokazyvayut, chto standartnyi scenarii inducirovannogo zvezdoobrazovaniya stalkivaetsya s bol'shimi trudnostyami. Delo v tom, chto vremya zhizni molekulyarnyh oblakov po vsei vidimosti men'she, chem polagali ranee. T.e., oblako ne mozhet mnogie milliony let "zhdat'", kogda do nego doidet udarnaya volna, chtoby zapustit' obrazovanie zvezd. T.o., scenarii inducirovannogo zvezdoobrazovaniya nuzhdaetsya v modifikacii. Vozmozhno, chto udarnye volny ot vspyshek sverhnovyh i zvezdnyh vetrov formiruyut potoki v mezhzvezdnoi srede, kotorye, v svoyu ochered', sposobstvuyut poyavleniyu molekulyarnyh oblakov, a uzh v nih potom nachinaetsya process formirovaniya zvezd.


astro-ph/0610853 Dvoistvennost' kak klyuchevoi faktor evolyucii protoplanetnyh diskov: obzor Spitcerom diskov v skoplenii Eta Hameleona (Binarity as a key factor in protoplanetary disk evolution: Spitzer disk census of the eta Chamaeleontis cluster)
Authors: J. Bouwman et al.
Comments: Accepted by ApJL

Na osnove detal'nyh nablyudenii na kosmicheskom infrakrasnom teleskope avtory delayut vyvod, chto dlya poyavleniya protoplanetnyh diskov sushestvenno luchshe, esli zvezda odinochnaya.

Iz 9 odinochnyh zvezd 7 pokazali nalichie diska, a iz 6 dvoinyh - tol'ko odna. Prichem, v sluchae dvoinoi eto ne disk vokrug vsei sistemy, a disk vokrug bolee massivnoi zvezdy.

Tak chto redko gde mozhno lyubovat'sya voshodom dvuh solnc.


miniobzor astro-ph/0610879 Gaia - mashina dlya obnaruzheniya belyh karlikov (Gaia - A White Dwarf Discovery Machine)
Authors: Stefan Jordan
Comments: 6 pages, proceedings of the 15 European Workshop on White Dwarfs, Leicester, UK, August 7-11, 2006

Opisyvaetsya, chto Gaia smozhet privnesti v astrofiziku belyh karlikov. Okazyvaetsya, ochen' mnogoe. Po suti budet sostavlena ochen' podrobnaya perepis' etih ob'ektov v solnechnoi okrestnosti, chto vazhno i dlya "arheologii", t.e. dlya vyyasneniya proshedshei evolyucii zvezd v solnechnoi okrestnosti, tak i dlya budushego kosmicheskogo detektora gravitacionnyi voln Lisa. Poskol'ku dlya nego blizkie dvoinye belye karliki budut sushestvennym istochnikom shuma.


Vypusk 142. 01-18 oktyabrya 2006

obzor astro-ph/0610356 Fizicheskie svoistva zvezd Vol'fa-Raie (Physical properties of Wolf-Rayer Stars)
Authors: Paul Crowther
Comments: 75 pages, 8 figures. To appear in Anuual review of astronomy and astrophysics

Kak uzhe neodnokratno otmechalos'. Anuual Review - eto glavnyi obzornyi zhurnal po astrofizike. (Pol'zuyas' sluchaem, otmechu, chto, buduchi protivnikom publikacii original'nyh statei na russkom, ya by vsyacheski privetstvoval poyavlenie horoshego obzornogo izdaniya po astronomii, v duhe sushestvovavshego VINITIshnogo.) Poetomu lyuboi obzor, napisannyi dlya dannogo izdaniya, estestvennym obrazom privlekaet vnimanie. Etot obzor napisan, kak vsem uzhe yasno iz nazvaniya, o zvezdah Vol'fa-Raie.


Vypusk 141. 15-30 sentyabrya 2006

astro-ph/0609709 Inducirovannoe zvezdoobrazovanie v okrestnosti massivnyh molodyh zvezd (Triggered Star Formation in the Environment of Young Massive Stars)
Authors: M. Gritschneder, T. Naab, F. Heitsch, A. Burkert
Comments: 4 pages, 2 figures. To appear in: "Triggered Star Formation in a Turbulent ISM", IAU Symposium 237, Prague, Czech Republic, August 2006; eds. B.G.Elmegreen & J. Palous

S pomosh'yu chislennogo modelirovaniya avtory pokazyvayut, chto ioniziruyushee izluchenie massivnyh molodyh zvezd sposobno inducirovat' zvezdoobrazovanie v blizkih molekulyarnyh oblakah.


astro-ph/0609742 Goryachii subkarlik + belyi karlik KPD 1930+2752: kandidat v praroditeli sverhnovyh tipa Ia (The hot subdwarf B + white dwarf binary KPD 1930+2752 - a Supernova Type Ia progenitor candidate)
Authors: S. Geier et al.
Comments: 10 pager, 11 figures, Astronomy & Astrophysics accepted

Sobstvenno, stat'ya privlekla moe vnimanie potomu, chto obsuzhdaemaya sistema schitaetsya odnim iz luchshih (na segodnyashnii den') kandidatov v budushie sverhnovye tipa Ia. Odnako takoi vyvod nuzhdaetsya v detal'nom nablyudatel'nom podtverzhdenii. Dlya etogo nado pokazat', chto, vo-pervyh, sistema sostoit iz "nuzhnyh" zvezd, a vo-vtoryh, chto ih summarnaya massa prevoshodit chandrasekarovskii predel.

Avtory pokazali, chto priroda kompan'onov udovletvoryaet trebovaniyam, pred'yavlyaemym k praroditelyam sverhnovyh Ia. S summarnoi massoi vse slozhnee. Delo v tom, chto ona okazalas' ochen' blizka k kriticheskoi. No vot s kakoi storony? Avtory polagayut bolee veroyatnym, chto massa vse-taki prevoshodit chandrasekarovskuyu. I, t.o., KPD 1930+2752 v samom dele yavlyaetsya edva li ne luchshim kandidatom v budushie sverhnovye.


obzor astro-ph/0609829 Himicheskii sostav zvezd s planetami: obzor (The Chemical Compositions of Stars with Planets: A Review)
Authors: Guillermo Gonzalez
Comments: 30 pages, invited review paper for PASP

Podrobnyi obzor, posvyashennyi tomu, kak vydelyayutsya svoim himicheskim sostavom zvezdy, vokrug kotoryh obnaruzheny ekzoplanetnye sistemy.


Vypusk 140. 01-15 sentyabrya 2006

astro-ph/0609045 Deficit ugleroda na vneshne zagryaznennyh belyh kardikah: ukazaniya na akkreciyu asteroidov (Carbon Deficiency in Externally-Polluted White Dwarfs: Evidence for Accretion of Asteroids)
Authors: M. Jura
Comments: 23 pages, 6 figures, accepted for ApJ

Interesnaya ideya. Okazyvaetsya, est' belye karliki, ch'i spektry govoryat o tom, chto na ih poverhnost' vypadalo kakoe-to vneshnee veshestvo, poetomu ih nazyvayut vneshne zagryaznennymi (externaly polluted). Obychno, eto veshestvo mezhzvezdnoi sredy. Odnako okazyvaetsya, chto sredi vneshne zagryaznennyh est' belye karliki s deficitom ugleroda. Takoe nedostatok ugleroda nel'zya ob'yasnit' akkreciei iz mezhzvezdnoi sredy. Avtor polagaet, chto belye karliki akkrecirovali asteroidy!


obzor astro-ph/0609389 Fizika zvezdnyh koron (Physics of Stellar Coronae)
Authors: M. Guedel
Comments: 1 pages, 42 figures, svmult style. To be published in Lecture Notes from summer school on "Turbulence and Fine Scale Structure in Solar and Astrophysical Plasmas"

Lekcii po fizike zvezdnyh koron.

Kak pishet avtor, eto vzglyad astronoma-zvezdnika na problemu. T.e., v lekciyah net slozhnyh teoreticheskih vykladok ili detal'nogo opisaniya fiziki. Tekst posvyashen v osnovnom dannym nablyudenii i ih interpretacii.


Vypusk 138. 01-31 iyulya 2006

astro-ph/0607401 Svyazany li gravitacionno Proksima i Al'fa Centavra? (Are Proxima and Alpha Centauri Gravitationally Bound?)
Authors: Jeremy G. Wertheimer, Gregory Laughlin
Comments: 10 pages total, 4 pages of text, 1 page of references, 3 figures, and 2 tables This article will be published in The Astronomical Journal

Okazyvaetsya, chto vopros etot ne tol'ko do sih por ne reshen, no dlya ego razresheniya nuzhny novye bolee tochnye nablyudeniya! Delo v tom, chto Proksima slishkom daleka ot pary zvezd, sostavlyayushih Al'fu Centavra. Rasstoyanie kak raz poryadka togo, na kotorom prilivnoe deistvie Galaktiki mozhet razrushit' sistemu. Veroyatno, chto Proksima seichas nahoditsya v apoastre svoei orbity, no mozhet byt', chto vse-taki tri zvezdy ne obrazuyut edinuyu sistemu. Tak chto bez novyh nablyudenii ne oboitis'.


astro-ph/0607490 Izobrazheniya planetnogo kompan'ona molodogo burogo karlika 2MASS J1207334-393254 po dannym HST NICMOS (HST NICMOS Imaging of the Planetary-mass Companion to the Young Brown Dwarf 2MASS J1207334-393254)
Authors: Inseok Song et al.
Comments: 18 pages, 3 figures, 3 tables. Accepted in ApJ

Pod nomerom vosem' v proshlogodnii spisok samyh vazhnyh astronomicheskih otkrytii (po publikaciyam v Arhive) ya vnes obnaruzhenie planetnogo sputnika u burogo karlika. Sushestvennym momentom yavlyaetsya to, chto udalos' poluchit' pryamoe izobrazhenie planety (ob etom takzhe mozhno prochest' v iyul'skom nomere "Vokrug Sveta").

Pervoe izobrazhenie bylo polucheno eshe v 2004 g., no tol'ko v 2005 byli polucheny podtverzhdeniya togo, chto dva ob'ekta (planeta i karlik) obrazuyut paru. Teper' zhe po novym dannym udalos' utochnit' rasstoyanie do sistemy (ono sostavlyaet 59+/-7 parsek) i rasstoyanie mezhdu komponentami (46+/-5 a.e. - eto v proekcii). Avtory eshe raz podcherkivayut, chto mozhno schitat' dokazannym, chto my imeem pervoe izobrazhenie vnesolnechnoi planety.


Vypusk 137. 16 iyunya - 30 iyunya 2006

astro-ph/0606467 Model' burnyh zvezdnyh sliyanii dlya ob'yasneniya tranzientnyh yavlenii (Violent Stellar Merger Model for Transient Events)
Authors: Noam Soker, Romuald Tylenda
Comments: Submitted to MNRAS

Sliyanie dvuh normal'nyh zvezd mozhet privesti v rezkomu vydeleniyu bol'shoi energii. V rezul'tate, my mozhem nablyudat' vspyshku, t.e. tranzientnyi istochnik. Avtory rassmatrivayut imenno takuyu model'. Oni polagayut, chto tak mozhno ob'yasnit' vspyshki tipa nablyudavsheisya u zvezdy V838 Monocerotis.

Osnovnoi vyvod sostoit v tom, chto vydelen interval otnosheniya mass, pri kotorom yarkie vspyshki vozmozhny. Slovami, eto mozhno opisat' kak "otnoshenie mass dolzhno byt' ne slishkom bol'shim i ne slishkom malym", kolichestvenno zhe: 0.003 Ob infrakrasnyh nablyudeniyah V838 Mon mozhno prochest' zdes': astro-ph/060691.


astro-ph/0606467 Produkty zhiznedeyatel'nosti zvezd (Life Products of Stars)
Authors: Aldo M. Serenelli, Masataka Fukugita
Comments: 26 pages, including 8 figures and 3 tables. Submitted to ApJS

V stat'e rassmotreno, kak zvezdy s massami ot 1 do 8 solnechnyh teryayut energiyu i massu v techenie zhizni. Na osnove sushestvuyushih evolyucionnyh trekov detal'no rassmotreno kogda, chto i v kakoi forme zvezdy vybrasyvayut vovne.

Na moi vzglyad, eto polezno ne tol'ko specialistam, no i vsem, interesuyushimsya zvezdnoi evolyuciei v detalyah.


Vypusk 136. 01 iyunya - 15 iyunya 2006

astro-ph/0606092 Issledovanie zvezd tipa RR Liry v Obzore Peremennosti Severnogo Neba (Analysis of RR Lyrae Stars in the Northern Sky Variability Survey)
Authors: K. Kinemuchi et al.
Comments: 68 pages, 26 figures, 9 tables, accepted to AJ

ROTSE (Robotic Optical Transient Search Experiment) - eto nebol'shoi obzornyi instrument, iznachal'no prednaznachennyi dlya poiska opticheskih tranzientov, svyazannyh s gamma-vspleskami. No vspleski, soprovozhdayushiesya dostatochno yarkoi opticheskoi vspyshkoi sluchayutsya nechasto, a obzory neba vedutsya postoyanno. Znachit, nado ispol'zovat' vsyu tu informaciyu, kotoraya "sama soboi" nakaplivaetsya.

V dannoi stat'e avtory predstavlyayut analiz obzora peremennyh zvezd tipa RR Liry yarche 14-i zvezdnoi velichiny. Vsego vydeleno 1197 kandidatov. Dlya 1188 postroeny horoshie krivye bleska. Dlya 589 udalos' dazhe poluchit' dannye po metallichnosti.


astro-ph/0606129 Ogranicheniya na sushestvovanie planety u Vegi po nablyudeniyam teplovogo IK izlucheniya na sisteme MMT s adaptivnoi optikoi (Thermal Infrared Constraint to a Planetary Companion of Vega with the MMT Adaptive Optics System)
Authors: Philip M. Hinz, A. N. Heinze, Suresh Sivanandam, Douglas L. Miller, Matthew A. Kenworthy, Guido Brusa, Melanie Freed, J.R.P. Angel
Comments: accepted to ApJ June 6, 2006

Po strukture raspredeleniya pyli vokrug Vegi bylo zapodozreno, chto zvezda mozhet imet' massivnuyu planetu na shirokoi orbite. Avtory proveli detal'nye nablyudeniya v infrakrasnom diapazone s pomosh'yu ustanovki MMT. I m udalos' postavit' ochen' ser'eznoe ogranichenie na parametry planety. Massa ee dolzhna byt' ne bolee 7 mass Yupitera, esli ee orbita bol'she 20 a.e.

V drugoi stat'e opisyvaetsya kamera Clio, prednaznachennaya dlya poiska planet i rabotayushaya na toi zhe ustanovke MMT.


astro-ph/0606276 O pervom pokolenii zvezd (On the First Generation of Stars)
Authors: Joseph Silk, Mathieu Langer
Comments: 7 pages, Submitted to MNRAS

Kak izvestno, v standartnoi kartine pervye zvezdy (t.n. Pokolenie III) byli ochen' massivnymi (do soten mass Solnca). Eto svyazano s ih maloi metallichnost'yu. Odnako, bol'shaya massa - eto massa fragmenta oblaka, iz kotorogo obrazuetsya zvezda. Massa ee rastet za schet akkrecii na iznachal'no ochen' malomassivnoe (0.01 massy solnca) yadryshko. V raschetah obychno prenebregayut vliyaniem magnitnogo polya na rost massy. Uchetu etogo vliyaniya i posvyashena stat'ya.

Avtory pokazyvayut, chto iz-za razvitiya magnito-vrashatel'noi neustoichivosti pole mozhet usilit'sya dostatochno dlya togo, chtoby stat' dinamicheski vazhnym. Itogom takogo razvitiya sobytii stanovitsya otnositel'no malaya (ne bolee 50) konechnaya massa zvezdy.

Avtory ne nastaivayut na tom, chto ih model' "edinstvenno vernaya". Odnako, vopros i v samom dele nuzhdaetsya v detal'nom analize.


astro-ph/0606354 Proishodit li bol'shinstvo planetarnyh tumannostei iz dvoinyh sistem? (Do most planetary nebulae derive from binaries? I Population synthesis model of the galactic planetary nebula population produced by singlestars and binaries)
Authors: Maxwell Moe, Orsola De Marco
Comments: 52 pages (referee format), 14 figures. Accepted by ApJ

Kak ya uzhe mnogokratno pisal, vopros o proishozhdenii planetarnyh tumannostei ostaetsya otkrytym. Delo v tom, chto v osnovnom eti ob'ekty bolee ili menee bipolyarny. Otklonenie ot sfericheskoi simmetrii mozhno ob'yasnyat' ili vliyaniem magnitnogo polya, ili dvoistvennost'yu central'noi zvezdy. Vot tut-to i zaryta sobaka!

Avtory provodyat detal'nyi populyacionnyi sintez s cel'yu razresheniya voprosa o proishozhdenii planetarnyh tumannostei. Vyvodom yavlyaetsya to, chto predpolozhenie o tom, chto imenno dvoinye porozhdayut tumannosti, horosho soglasuetsya s rezul'tatami raboty.


Vypusk 135. 22 aprelya - 31 maya 2006

astro-ph/0604533 Vrashenie zvezd: klyuch k proishozhdeniyu massivnyh zvezd (Stellar Rotation: A Clue to the Origin of High Mass Stars?)
Authors: S. C. Wolff, S. E. Strom, D. Dror, L. Lanz, K. Venn
Comments: 19 pages, two tables, 2 figures

Avtory privodyat bol'shoe kolichestvo dannyh po vrasheniyu molodyh zvezd raznyh mass (ot 0.2 do 50 mass Solnca). Osnovnoi vopros, kotoryi zadavali sebe avtory takov: mozhno li po dannym o vrashenii sdelat' vyvod o tom, obrazuyutsya li zvezdy raznyh mass podobnym obrazom, ili zhe massivnye i malomassivnye poyavlyayutsya na svet po-raznomu. Osnovnoi vyvod: vrashatel'nye svoistva ne soderzhat nikakogo skachka pri uvelichenii massy. T.o., polagayut avtory, dolzhen sushestvovat' edinyi mehanizm, otvetstvennyi za poyavlenie zvezd raznyh mass.


obzor astro-ph/0604572 Spektroskopiya massivnyh zvezd (Spectroscopy of Massive Stars)
Authors: Yael Naze
Comments: review published by the Liege Royal Societey of Sciences, 31 pages without figures; Journal-ref: Bull.Soc.Roy.Sci.Liege 75 (2006) 20-61

Poleznyi obzor.


astro-ph/0605401 Poisk kilogaussovyh magnitnyh polei u belyh karlikov i goryachih subkarlikov (A search for kilogauss magnetic fields in white dwarfs and hot subdwarf stars)
Authors: G. Valyavin et al.
Comments: accepted for publication in the Astrphysical Journal

Pryamye opredeleniya magnitnyh polei u belyh karlikov - vazhnaya zadacha. Yasno, chto chem men'she polya, tem slozhnee ih obnaruzhit'. Polya poryadka MegaGaussa harakterny lish' dlya maloi doli karlikov. A vot kilogaussovye polya tipichny uzhe dlya 25 procentov etih kompaktnyh zvezd.

(Pol'zuyas' sluchaem, hochu anonsirovat' svoyu stat'yu v iyul'skom nomere "Vokrug sveta", gde budet i pro belye karliki).


Vypusk 134. 12-21 aprelya 2006

astro-ph/0604366 Analiz belyh karlikov s yadrami iz strannogo veshestva (Analysis of White Dwarfs with Strange-Matter Cores)
Authors: G. J. Mathews et al.
Comments: 11 pages, 6 figures, accepted for publication in J. Phys. G: Nucl. Part. Phys

And if you go chasing rabbits
And you know you're going to fall

K strannym zvezdam vse uzhe privykli. Eto gipoteticheskie ob'ekty, pohozhie na neitronnye zvezdy, no soderzhashie vnutri sebya materiyu, sostoyayushuyu iz svobodnyh kvarkov. Mogut sushestvovat' chisto kvarkovye zvezdy. Oni celikom sostoyat iz kvarkovoi materii (vozmozhno, za isklyucheniem ochen'-ochen' tonkoi obolochki). Mogut sushestvovat' t.n. gibridnye zvezdy. Eto, po suti, neitronnye zvezdy, v central'nyh oblastyah kotoryh obrazovalos' kvarkovoe yadro. A mogut sushestvovat' i drugie "zveri".

Fridolin Veber i Norman Gledenning nekotoroe vremya nazad razrabotali model' t.n. "strannyh karlikov". Eto kompaktnye ob'ekty, pohozhie na belye karliki, no soderzhashie vnutri kvarkovoe veshestvo. Plotnost' veshestva v belyh karlikah nedostatochna dlya samostoyatel'nogo poyavleniya fazy svobodnyh kvarkov. No, esli tuda zaletit "strapel'ka" (termin, propagandiruemyi mnoyu v kachestve perevoda slova strangelet - komochek strannogo veshestva), to takaya faza vozniknet. Krome togo, obrazovanie takoi fazy vozmozhno eshe na stadii zvezdy glavnoi posledovatel'nosti, iz kotoroi potom "vylupitsya" belyi karlik, tochnee strannyi belyi karlik. V stat'e rech' idet imenno o takih zvezdah.

V nachale stat'i, avtory privodyat nablyudatel'nye dannye po massam i radiusam belyh karlikov. Zatem, iz nablyudaemogo massiva oni vydelyayut gruppu ob'ektov, kotorye mogut byt' etimi samymi strannymi karlikami. Posle eta gruppa zvezd analiziruetsya. Vydelennye ob'ekty harakterizuyutsya malym radiusom. V tradicionnom podhode eto svoistvo ob'yasnyaetsya nalichiem zheleznyh yader. V stat'e avtory privodyat argumenty protiv takoi interpretacii, predlagaya vzamen ob'yasnenie, osnovannoe na sushestvovanii strannogo veshestva vnutri etih zvezd.


Vypusk 132. 22-31 marta 2006

astro-ph/0603774 Oskolochnye diski vokrug belyh karlikov (Debris Disks Around White Dwarfs: The DAZ Connection)
Authors: Mukremin Kilic, Ted von Hippel, S. K. Leggett, D. E. Winget
Comments: 17 pages, ApJ, in press

Stat'ya privlekla moe vnimanie v pervuyu ochered' potomu, chto ya ran'she nichego ne slyshal o podobnyh diskah vokrug etih ob'ektov. Okazyvaetsya, diski byli predskazany i voznikayut oni skoree vsego potomu, chto orbity planet, komet, asteroidov i t.p. stanovyatsya neustoichivymi vo vremya stadii krasnogo giganta i posleduyushego sbrosa obolochki. V rezul'tate takoi neustoichivosti tela nachinayut letat' po sisteme kto vo chto gorazd, chto privodit k stolknoveniyam. Vot oskolki etih stolknovenii i formiruyut diski.

Do etoi raboty byl izvesten vsego lish' odin odinochnyi belyi karlik s oskolochnym diskom. Eto byl ob'ekt G29-38. Takzhe disk byl zapodozren u tyazhelogo karlika GD362. V eto stat'e avtory predstavlyayut rezul'taty detal'nyh nablyudenii 20 belyh karlikov. Sushestvovanie diska podtverzhdeno u GD29-38 i GD362. Krome togo, u GD56 (WD0408-041) takzhe otchetlivo vidny sledy diska. On, t.o., stal tret'im belym karlikom, vokrug kotorogo stolknoveniya malyh tel porodili disk iz ih oblomkov. Veroyatno, chto i chetvertyi karlik - WD1150-153 takzhe obladaet oskolochnym diskom.

Priyatno, chto iz Arhiva vse vremya uznaesh' chto-to novoe dlya sebya :)


Vypusk 131. 13-21 marta 2006

astro-ph/0603444 Massa Dzhinsa i proishozhdenie izloma v nachal'noi funkcii mass (The Jeans mass and the origin of the knee in the IMF)
Authors: I. A. Bonnell et al.
Comments: 6 pages, 4 figures, MNRAS in press

Na osnovanii chislennyh raschetov avtory prihodyat k vyvodu o tom, chto nalichie izloma v nachal'noi funkcii mass i ego mestopolozhenie (na massah poryadka solnechnoi) opredelyaetsya ne nachal'nymi usloviyami v szhimayushemsya oblake, a mehanizmom ohlazhdeniya.

Sm. takzhe obzor, posvyashennyi problemam v izuchenii nachal'noi funkcii mass.


astro-ph/0603520 Vega - bystrovrashayushayasya zvezda (Vega is a rapidly rotating star)
Authors: D. M. Peterson et al.
Comments: 10 pages, 2 figures, a Letter to Nature, tentatively scheduled for April 13

Vega - odna iz dvuh samyh yarkih zvezd severnogo neba. Krome togo, ona ispol'zuetsya v kachestve standarta. Tem ne menee, nekotorye ee svoistva postoyanno utochnyayutsya. V chastnosti, davno bylo zamecheno, chto Vega neskol'ko yarche, chem pohozhie na nee zvezdy. Polagali, chto eto mozhet byt' svyazano s tem, chto
1. Zvezda bystro vrashaetsya
2. My vidim ee pochti s polyusa.
I vot udalos' pokazat', chto eto v samom dele tak.

S pomosh'yu interferometricheskih nablyudenii udalos' vyyavit' raspredelenie yarkosti po vidimoi poverhnosti Vegi (sm . risunok). Ot polyusa k ekvatory temperatura spadaet na 2400 gradusov! Chtoby eto ob'yasnit', trebuetsya predpolozhit' bystroe vrashenie. Ved' togda zvezda budet splyusnutoi, a znachit, ekvator budet holodnee, chem polyarnye oblasti. Pri etom skorost' ochen' velika, na ekvatore ona dostigaet 270 km/s. Esli ona byla by bol'she hotya by na 8 procentov, to veshestvo nachalo by ottekat' ot ekvatora zvezdy.


Primerno tak vidna Vega s Zemli.

Novye nablyudeniya pozvolili utochnit' parametry Vegi. Massa ravna primerno 2.3 massy Solnca. Vozrast 386 +/- 16 millionov let. Eto chut' bol'she, chem polagalos' ranee (hotya v predelah oshibok znacheniya i sovpadayut). Odnako, eti znacheniya chuvstvitel'ny k predpolozheniyam o himicheskom sostave Vegi, tak chto oni eshe mogut utochnit'sya v budushem.


Vypusk 130. 01-13 marta 2006

astro-ph/0603025 Sverhnovaya 2002kg tipa IIn: Vspyshka yarkoi goluboi peremennoi v NGC 2403 (The Type IIn Supernova 2002kg: The Outburst of a Luminous Blue Variable Star in NGC 2403)
Authors: Schuyler D. Van Dyk et al.
Comments: 22 pages, 15 figures, submitted to PASP

S chem mozhno pereputat' vzryv sverhnovoi? Avtory polagayut, chto neobychnaya sverhnovaya, nablyudavshayasya v 2002 godu, est' ni chto inoe, kak vspyshka yarkoi goluboi peremennoi ( Luminous Blue Variable, nekotorye kartinki, svyazannye s etimi massivnymi zvezdami, mozhno posmotret' zdes'). Takie sobytiya uzhe nablyudalis'. Naprimer, izvestny moshneishie vspyshki Eta Kilya.

Avtory polagayut, chto burnaya zhizn' massivnyh predsverhnovyh soprovozhdaetsya bol'shim kolichestvom takih vspyshek, i chto mnogie sobytiya, ranee klassificirovannye kak sverhnovye, na samom dele yavlyayutsya rezul'tatom ne smerti, a agonii massivnyh zvezd.

Eshe odna stat'ya, posvyashennaya toi zhe tematike, poyavilas' dnem pozzhe: astro-ph/0603056.


astro-ph/0603098 Novye ob'ekty tipa Gamma Kassiopei: rentgenovskie i opticheskie nablyudeniya SAO49725 i HD161103 (New Gamma Cas-like objects: X-ray and optical observations of SAO49725 and HD161103)
Authors: Raimundo Lopes de Oliveira et al.
Comments: 14 pages, 9 figs, accepted for publication in A&A

Gamma Kassiopei - izvestneishaya Ve-zvezda. Ona takzhe znamenita izbytkom rentgenovskogo izlucheniya (izbytkom po sravneniyu s obychnoi odinochnoi zvezdoi etogo klassa). Prichiny vozniknoveniya "lishnih rentgen" ne yasny. Osnovnyh gipotez dve: ili eto svyazano s vzaimodeistviem potokov plazmy (naprimer, zvezdnogo vetra i okolozvezdnogo diska), ili zhe est' kompaktnyi sputnik, skoree vsego belyi karlik.

V etoi stat'e avtory rasskazyvayut ob obnaruzhenii eshe dvuh zvezd, svoistva kotoryh analogichny svoistvam Gamma Kassiopei. Po vsei vidimosti, est' celyi klass takih ob'ektov. Esli eto dvoinye sistemy, to kompan'onami Ve-zvezd dolzhny byt' belye karliki. V budushem, takie sistemy dolzhny prevrashat'sya v interesnye pary staryi belyi karlik + molodoi radiopul'sar. Pohozhe, chto takie primery uzhe naideny (ya rasskazyval o nih v obzorah).


astro-ph/0603113 Nablyudaemye planetarnye tumannosti kak ostatki vzaimodeistvuyushih dvoinyh sistem (Observed Planetary Nebulae as Descendants of Interacting Binary Systems)
Authors: Noam Soker
Comments: Submitted To ApJ Lett, 4 pages

Noam Soker davno i posledovatel'no otstaivaet tochku zreniya o svyazi planetarnyh tumannostei s dvoinymi sistemami. V bolee rannih rabotah obychno obsuzhdalas' problema bipolyarnyh tumannostei. Zdes' zhe rech' idet uzhe obo vseh nablyudaemyh.

Avtor ishodit iz dannyh, kotorye govoryat o tom, chto temp rozhdeniya planetarnyh tumannostei vtroe men'she tempa rozhdeniya belyh karlikov. T.e. v 2/3 sluchaev, kogda poyavlyaetsya belyi karlik, my ne vidim tumannosti. Esli zvezda odinochnaya, polagaet Soker, to tumannost' budet slishkom slaboi, chtoby ee uvidet'. Vse eti neulovimye tumannosti dolzhny byt' prakticheski sfericheski simmetrichnymi, t.k. asimmetriya (nablyudayushayasya v toi ili inoi stepeni pochti u vseh izvestnyh planetarnyh tumannostei, a tochnee v 97 procentah sluchaev), po mneniyu Sokera, svyazana imenno s vzaimodeistviem s kompan'onom.

Otmechu, chto vse eto poka gipotezy. Tak, naprimer, mozhet byt' velika rol' magnitnyh polei zvezdy v formirovanii bipolyarnoi tumannosti. Osnovnym predskazaniem etoi raboty yavlyaetsya vozmozhnost' obnaruzheniya bol'shogo kolichestva slabyh tumannostei, kotorye vse budut simmetrichnymi. Pozhivem - uvidim.


astro-ph/0603185 Akkrecionno-diffuzionnyi scenarii dlya metallov na holodnyh belyh karlikah (The accretion-diffusion scenario for metals in cool white dwarfs)
Authors: D. Koester, D. Wilken
Comments: 9 pages, To be published in A&A

Akkreciya na odinochnye kompaktnye ob'ekty mozhet ispol'zovat'sya kak tester mezhzvezdnoi sredy. Eto vazhno. K sozhaleniyu, odinochnyh akkreciruyushih neitronnyh zvezd poka ne otkryto. A vot belye karliki - est'.

Avtory rassmatrivayut tri s lishnim dyuzhiny holodnyh (holodnee 25 000K) belyh karlikov. Dlya nih effekty akkrecii mezhzvezdnogo veshestva uzhe vazhny. Sootvetstvenno, mozhno ocenit' temp akkrecii. A znachit, mozhno ponyat' svoistva mezhzvezdnoi sredy v neposredstvennoi blizosti ot belyh karlikov. V chastnosti, okazyvaetsya, chto ochen' vazhny malen'kie (poryadka parseka) oblachka teplovogo chastichno ionizovannogo gaza.


astro-ph/0603219 HD 98618: zvezda, ochen' pohozhaya na nashe solnce (HD 98618: A Star Closely Resembling our Sun)
Authors: Jorge Melendez et al.
Comments: ApJ letters, in press

Ishut, no tak i ne mogut naiti.... blizneca Solnca.

Dostatochno vazhno iskat' i izuchat' zvezdy, kak mozhno bolee pohozhie na nashe Solnce. Seichas blizhaishim dvoinikom schitaetsya zvezda 18 skorpiona (ee opoznali kak prakticheski polnuyu kopiyu Solnca okolo 10 let nazad). Tem ne menee, poiski dvoinikov prodolzhayutsya.

Avtory izuchili detal'nye spektry 16 solncepodobnyh zvezd. Rezul'tatom stalo vyyavlenie zvezdy HD 98618 v kachestve eshe odnogo "pochti dvoinika". Pochti, potomu chto, kak i v sluchae 18 skorpiona, nekotorye otlichiya vse-taki est'.

Razumeetsya, avtory govoryat kakie-to slova o zonah obitaniya i probleme SETI.


Vypusk 129. 20-28 fevralya 2006

miniobzor astro-ph/0602469 Rassmotrenie zvezdnoi nachal'noi funkcii mass (Understanding the Stellar Initial Mass Function)
Authors: Richard B. Larson
Comments: 5 pages, text only. Invited talk presented at the 11th Latin American Regional IAU Meeting, Pucon, Chile, December 2005. To be published by Revista Mexicana de Astronomia y Astrofisica

Obsuzhdayutsya svoistva funkcii mass zvezd. Avtor osobo vydelyaet nalichie maksimuma na massah poryadka neskol'kih desyatyh massy Solnca i stepennoi hvost v storonu bol'shih mass, pohozhii na predlozhennuyu v 1955 g. original'nuyu (i do sih por ochen' chasto ispol'zuemuyu) Salpiterovskuyu funkciyu mass.

Nablyudaemye parametry uvyazyvayutsya so svoistvami modeli zvezdoobrazovaniya. Nalichie maksimuma na spektre mass (t.e. vydelennoi massy) mozhet mnogoe rasskazat' o mehanizme (tochnee, o mehanizmah) zvezdoobrazovaniya. Esli massy zvezd (s massami menee odnoi solnechnoi) opredelyayutsya dzhinsovskoi massoi v kollapsiruyushem oblake, to nado ponyat', chto opredelyaet dzhinsovskuyu massu. Vazhnyi moment - temperatura. T.e. izmeneniya temperatury (v tom chisle i vo vremya kollapsa) mogut imet' bol'shoe znachenie. V 1985 godu Larson vyskazal gipotezu, chto kriticheskaya massa, sootvetstvuyushaya maksimumu, opredelyaetsya tem, chto est' vydelennaya dzhinsovskaya massa, pri kotoroi proishodit "temperaturnoe svyazyvanie" gaza i pyli. V predlagaemom obzore obsuzhdaetsya eta situaciya i privodyatsya dannye nedavnih chislennyh eksperimentov, podtverzhdayushih gipotezu.

Krome togo, kratko obsuzhdaetsya i povedenie funkcii mass dlya massivnyh zvezd. Tam situaciya inaya. Massa opredelyaetsya uzhe ne stol'ko fragmentaciei, skol'ko posleduyushei akkreciei.

Otdel'no obsuzhdaetsya funkciya mass zvezd v samoi central'noi oblasti nashei Galaktiki. Iz-za vysokoi temperatury pyli tam nevozmozhno formirovanie malomassivnyh zvezd. Vse eto privodit k tomu, chto funkciya mass sil'no obogashena massivnymi zvezdami i imeet nebol'shoi naklon.


astro-ph/0602004 OV-zvezdy v okrestnosti Solnca I: Analiz prostranstvennogo raspredeleniya (OB Stars in the Solar Neighborhood I: Analysis of their Spatial Distribution)
Authors: F. Elias, J. Cabrera-Cano, E.J. Alfaro
Comments: 28 pages including 9 Postscript figures, one of them in color. Accepted for publication in The Astronomical Journal, 30 January 2006

Stat'ya horosho illyustriruet, s kakimi trudnosyatmi stalkivayutsya astronomy, izuchaya dazhe "udobnye" ob'ekty.

Avtory stroyat model' raspredeleniya massivnyh zvezd v okrestnosti Solnca. Rech' idet o rasstoyaniyah do 1 kpk i zvezdah spektral'nyh klassov O-V. Kak izvestno, v nashei okrestnosti dominiruet t.n. Poyas Gulda. Sotvetstvenno, avtory stroyat dvuhkomponentnuyu model', v kotoroi zvezdy vhodyat ili v galakticheskii disk ili v Poyas.

Zadacha sostoit v tochnom opredelenii parametrov modeli. Prihoditsya uchityvat' mnogochislennye selekcionnye effekty. Po suti, avtory razrabotali novyi metod raboty s podobnymi dannymi. Tem ne menee, model' vse ravno ostaetsya lish' priblizhennym opisanie deistvitel'nosti...


astro-ph/0602501 Opticheskaya registraciya dvuh kompan'onov pul'sarov v dvoinyh sistemah promezhutochnyh mass (Optical Detection of Two Intermediate Mass Binary Pulsar Companions)
Authors: B. A. Jacoby et al.
Comments: 9 pages, 2 figures, accepted for publication in ApJL

Na krupnom nazemnom teleskope v observatorii im. Magellana avtory proveli poisk opticheskogo izlucheniya ot shesti belyh karlikov, yavlyayushihsya kompan'onami radiopul'sarov. Ne vse eti pul'sary yavlyayutsya millisekundnymi. Odin - vpolne normal'nyi molodoi pul'sar (PSR J1141-6545). No uvidet' belyi karlik v optike udalos' tol'ko v dvuh sluchayah, i vo vseh nih kompan'onom yavlyaetsya millisekundnyi pul'sar. Oba etih sluchaya vydelyaet to, chto oni nahodyatsya dovol'no blizko ot nas (menee 1 kpk), tak chto bolee glubokie nablyudeniya mogut potom dat' polozhitel'nyi rezul'tat i dlya drugih sistem.

Vse eto ochen' vazhno, t.k. dlya belyh karlikov mozhno opredelyat' vozrast, esli izvestna ih temperatura (i massa).


Vypusk 128. 13-20 fevralya 2006

miniobzor astro-ph/0602244 Sotrudnichestvo professionalov i lyubitelei i AAVSO (Pro-Am Collaboration and the AAVSO)
Authors: Arne A. Henden
Comments:15 pages, 10 figures, 2006, ASPC 349, 165

Opisany primery sotrudnichestva professionalov i lyubitelei po opytu AAVSO. Istoriya nachinaetsya azh s 19 veka, kogda Louvell priglasil na rabotu Slaifera (lyubitel' priglasil professionala, kstati). Odnako osnovnoe vnimanie udelyaetsya, konechno, bolee blizkomu k nam vremeni.

Obsuzhdaetsya, kak mozhno sdelat' sotrudnichestvo bolee plodotvornym.


obzor astro-ph/0602291 Gazovye planety, protozvezdy i molodye burye karliki: rozhdenie i sud'ba (Gaseous Planets, Protostars And Young Brown Dwarfs : Birth And Fate)
Authors: G. Chabrier et al.
Comments: Invited Review, Protostars and Planets V (Hawai, October 2005)

Podrobnyi obzor, posvyashennyi tematikam, privedennym v nazvanii. Rekomenduyu.


astro-ph/0602292 HST/ACS mnogocvetnoe koronograficheskoe izobrazhenie ostatochnogo diska vokrug Beta Zhivopisca (HST/ACS Multiband Coronagraphic Imaging of the Debris Disk around Beta Pictoris)
Authors: D. A. Golimowski et al.
Comments: 38 pages (including 21 figures and 4 tables)

Po dannym mnogocvetnyh nablyudenii na Kosmicheskom teleskope podtverzhdena slozhnaya struktura diska vokrug zvezdy Beta Zhivopisca. Nablyudeniya provodilis' s pomosh'yu koronografa, chtoby ubrat' meshayushii svet samoi zvezdy. Eto samye detal'nye dannye po okolozvezdnym diskam na masshtabe 30-300 a.e. ot central'noi zvezdy.


Snimki sdelany na Kosmicheskom teleskope. Razmer izobrazheniya 29 na 10 uglovyh sekund. Na dvuh verhnih snimkah pokazan disk vokrug Beta Zhivopisca. Na nizhnem - zvezda sravneniya - Al'fa Zhivopisca. PSF feature - tehnicheskii defekt koronografa, proishozhdenie kotorogo poka neizvestno. Vidno, chto PSF detal' ne menyaet svoego polozheniya pri izmenenii orientacii teleskopa, a disk (sravnite dva verhnih izobrazheniya) - menyaet.

Pokazano, chto vnutrennyaya chast' struktury vokrug zvezdy predstavlyaet soboi otdel'nyi disk, naklonennyi pod uglov okolo 5 gradusov po otnosheniyu k vneshnemu (osnovnomu) disku. Dva diska ili imeyut raznyi sostav granul (grains), ili raznoe raspredelenie granul po razmeru.


Pokazano obrabotannoe izobrazhenie (cveta uslovnye), na kotorom viden vnutrennii disk, naklonennyi k vneshnemu. Izobrazhenie v central'noi chasti iskazheno pri ubiranii sveta zvezdy.


Vypusk 127. 01-12 fevralya 2006

obzor astro-ph/0602012 Obrazovanie massivnyh zvezd (The Formation of Massive Stars)
Authors: H. Beuther, E. B. Churchwell, C. F. McKee, J. C. Tan
Comments: 16 pages, 3 figures, Proceedings to Protostars and Planets V, Hawaii 10/05, the high-resolution version can be found at this http URL

Seriya konferencii "Protozvezdy i planety" - ochen' vazhnaya i interesnaya. Imenno seichas v Arhive poyavlyaetsya massa statei iz gotovyashegosya sbornika trudov ocherednoi proshedshei vstrechi.

V etom obzore, kak yasno iz nazvaniya, rassmatrivaetsya obrazovanie massivnyh zvezd.


obzor astro-ph/0602122 Ne odinoki: proslezhivanie proishozhdeniya ochen' malomassivnyh zvezd i buryh karlikov po ih kratnosti (Not Alone: Tracing the Origins of Very Low Mass Stars and Brown Dwarfs Through Multiplicity Studies)
Authors: Adam J. Burgasser et al.
Comments: 16 pages, 7 figures, contributed chapter for Planets and Protostars V meeting (October 2005); full table of VLM binaries can be obtained at this http URL: http://paperclip.as.arizona.edu/~nsiegler/VLM_binaries/

V mehanizme (ili mehanizmah?) formirovaniya malomassivnyh zvezd i buryh karlikov eshe ochen' mnogo neyasnogo. Prakticheski vse shodyatsya vo mnenii, chto issledovaniya dvoistvennosti etih ob'ektov mozhet prolit' svet na imeyushiesya zagadki. Ved' yasno, chto kakie-to mehanizmy budut davat' bol'shuyu dolyu dvoinyh sistem, kakie-to maluyu. Raznymi mogut byt' raspredeleniya razlichnyh parametrov dvoinyh (naprimer, otnoshenie mass, dolya sistem na shirokih orbitah i t.p.). V predlagaemoi stat'e avtory s pomosh'yu nablyudenii pytayutsya proyasnit' situaciyu.

Otmechu dva rezul'tata.
1. Sredi malomassivnyh zvezd men'she dolya shirokih (slabosvyazannyh sistem).
2. Zvezdy, obrazovavshiesya v plotnyh skopleniyah i v oblastyah s nizkoi zvezdnoi plotnost'yu, otlichayutsya drug ot druga po parametram, svyazannym s dvoistvennost'yu.


astro-ph/0602146 Otkrytie chrezvychaino massivnogo skopleniya krasnyh sverhgigantov (Discovery of an Extraordinarily Massive Cluster of Red Supergiants)
Authors: Donald F. Figer et al.
Comments: 48 pages, ApJ, accepted

Na rasstoyanii primerno 5-6 kpk ot nas otkryto ochen' massivnoe zvezdnoe skoplenie. Ono vklyuchaet v sebya kak minimum 14 krasnyh sverhgigantov (do etogo samoe bogatoe iz izvestnyh skoplenii krasnyh sverhgigantov soderzhit vsego 5 takih ob'ektov). Vozrast skopleniya 7-12 millionov let. Massa skopleniya 20 000 - 40 000 mass Solnca. 99% zvezd eshe sohranilis'. Vzorvalas' malaya dolya samyh massivnyh. Temp sverhnovyh v etom skoplenii seichas ochen' vysok: odna vspyshka chashe chem raz v 100 000 let (mozhet byt' dazhe dve vspyshki za 100 000 let). Avtory polagayut, chto poslednyaya sverhnovaya vspyhnula tam okolo 1000 let nazad.

Nablyudeniya provodilis' avtorami v osnovnom v IK diapazone, no v etom skoplenii izvestny i rentgenovskie, i radio istochniki.


Pokazany dannye 2MASS.


Chernye kruzhki sootvetstvuyut sverhgigantam. Plyusom otmechen rentgenovskii istochnik. Svetlym kruzhkom - mazernyi istochnik, po kotoromu opredelyalos' rasstoyanie do skopleniya. Kvadraty - istochniki iz bazy dannyh SIMBAD, v osnovnom eto radioistochniki.


Vypusk 125. 18-20 yanvarya 2006

miniobzor astro-ph/0601346 Kratnost', aktivnost' i bystroe vrashenie zvezd rannih spektral'nyh klassov (Multiplicity, activity and fast rotation in early-type stars)
Authors: Ignacio Negueruela
Comments: Review to appear in "Active OB Stars: Laboratories for Stellar & Circumstellar Physics", eds. S. Stefl, S. P. Owocki & A. Okazaki. ASP Conf. Ser. 2006, in press (uses asp style).

Obzor posvyashen fenomenu Ve-zvezd. Eto zvezdy klasa V s emissionnymi liniyami v spektre. Dolya takih zvezd sredi vseh massivnyh dostatochno velika, krome togo horosho izvestny rentgenovskie sistemy s Ve-zvezdami, sostavlyayushie bOl'shuyu chast' vseh rentgenovskih dvoinyh.

V osnovnom rech' idet o proishozhdenii Ve-zvezd. Rezyume: neponyatno, kak oni obrazuyutsya. Tochnee tak, yasno, chto est' neskol'ko kanalov obrazovaniya Ve-zvezd, prichem nekotorye kanaly neizvestny.

Shiroko rasprostraneno mnenie, chto Ve-zvezdy mogut obrazovyvat'sya vo vzaimodeistvuyushih dvoinyh za schet perenosa massy s bolee massivnogo kompan'ona. I etot mehanizm rabotaet! No, kak yasno iz obzora, ne dlya vseh zvezd. Prichem i dolya teh, dlya kotoryh rabotaet, ne yasna. Tak chto, kak obychno, mnogoe sdelano, no mnogoe eshe predstoit!


astro-ph/0601375 Kratnost' zvezd i nachal'naya funkciya mass: bol'shinstvo zvezd rozhdaetsya odinochnymi (Stellar Multiplicity and the IMF: Most Stars Are Single Born)
Authors: Charles J. Lada
Comments: Submitted to Astrophysical Journal Letters, 5 pages, 2 figures

Na osnove poslednih dannyh po zvezdam pozdnih spektral'nyh klassov delaetsya vyvod o tom, chto bol'shinstvo zvezd v Galaktike vse-taki odinochnye. Na samom dele, rezul'tat vse-taki kolichestvennyi, a ne kachestvennyi (na moi vzglyad). Esli ranee schitali, chto 2/3 zvezd dvoinye, to Lada govorit, chto 2/3 odinochnye. Te, kto v raschetah schitali, chto 1/2 zvezd dvoinye, mogut nichego v raschetah ne menyat'! Krome togo, odinochnost' yavlyaetsya v osnovnom svoistvom malomassivnyh zvezd (spektral'nye klassy K i pozdnee). Poskol'ku imenno eti zvezdy naibolee mnogochislenny, to otsyuda i sleduet vyvod o tom, chto bOl'shaya chast' zvezd v Galaktike odinochnye. Kstati skazat', tot fakt, chto dvoistvennost' menyaetsya dlya zvezd raznyh mass, dolzhen sushestvenno vliyat' na raschety metodom populyacionnogo sinteza dlya tesnyh dvoinyh sistem. Naskol'ko ya znayu, vse schitayut, chto dolya dvoinyh ne zavisit ot massy kompan'onov. Hotya obychno v raschetah interesuyutsya massivnymi sistemami (t.e. hotya by odin komponent dostatochno massiven, chtoby uspet' proevolyucionirovat' do kompaktnogo ostatka), a dlya takih sistem vse, vrode by, v poryadke (osobenno esli uchest', chto raspredelenie komponent po massam obychno prinimaetsya takim, chto naibolee veroyatny komponenty ravnyh mass).

Poluchennyi rezul'tat ochen' vazhen dlya teorii obrazovaniya zvezd (i planet).


astro-ph/0601440 Otkrytie blizhaishego korichnevogo karlika? (Discovery of the Closest Brown Dwarf to the Sun? A Methane Rich Brown Dwarf around the Nearby M8.5 Star SCR 1845-6357)
Authors: B.A. Biller, M. Kasper, L.M. Close, W. Brandner, S. Kellner
Comments: 5 pages, 3 figures. Submitted to the Astrophysical Journal. Some figures are currently omitted and will be supplied with the final, accepted version

V nachale - kur'ez. Pervyi raz ya vizhu, chtoby redaktory astro-ph propustili takoi glyuk, kak dvoinaya stat'ya: t.e. nomera 440 i 441 - eto odna i ta zhe rabota. Nadeyus', chto k sboyu v numeracii eto ne privedet.

Teper' o suti. Po dannym nablyudenii na VLT u blizkoi zvezdy SCR 1845-6357 (8.5 pk ot Solnca) obnaruzhen kompan'on. Pohozhe, chto eto korichnevyi (buryi) karlik. Poka, razumeetsya, ne ustanovlena fizicheskaya svyaz' zvezdy i karlika (t.e. ne isklyucheno, chto eto fonovyi ob'ekt), no skoree vsego eto real'naya para.


Vypusk 125. 18-20 yanvarya 2006

miniobzor astro-ph/0601346 Kratnost', aktivnost' i bystroe vrashenie zvezd rannih spektral'nyh klassov (Multiplicity, activity and fast rotation in early-type stars)
Authors: Ignacio Negueruela
Comments: Review to appear in "Active OB Stars: Laboratories for Stellar & Circumstellar Physics", eds. S. Stefl, S. P. Owocki & A. Okazaki. ASP Conf. Ser. 2006, in press (uses asp style).

Obzor posvyashen fenomenu Ve-zvezd. Eto zvezdy klasa V s emissionnymi liniyami v spektre. Dolya takih zvezd sredi vseh massivnyh dostatochno velika, krome togo horosho izvestny rentgenovskie sistemy s Ve-zvezdami, sostavlyayushie bOl'shuyu chast' vseh rentgenovskih dvoinyh.

V osnovnom rech' idet o proishozhdenii Ve-zvezd. Rezyume: neponyatno, kak oni obrazuyutsya. Tochnee tak, yasno, chto est' neskol'ko kanalov obrazovaniya Ve-zvezd, prichem nekotorye kanaly neizvestny.

Shiroko rasprostraneno mnenie, chto Ve-zvezdy mogut obrazovyvat'sya vo vzaimodeistvuyushih dvoinyh za schet perenosa massy s bolee massivnogo kompan'ona. I etot mehanizm rabotaet! No, kak yasno iz obzora, ne dlya vseh zvezd. Prichem i dolya teh, dlya kotoryh rabotaet, ne yasna. Tak chto, kak obychno, mnogoe sdelano, no mnogoe eshe predstoit!


astro-ph/0601375 Kratnost' zvezd i nachal'naya funkciya mass: bol'shinstvo zvezd rozhdaetsya odinochnymi (Stellar Multiplicity and the IMF: Most Stars Are Single Born)
Authors: Charles J. Lada
Comments: Submitted to Astrophysical Journal Letters, 5 pages, 2 figures

Na osnove poslednih dannyh po zvezdam pozdnih spektral'nyh klassov delaetsya vyvod o tom, chto bol'shinstvo zvezd v Galaktike vse-taki odinochnye. Na samom dele, rezul'tat vse-taki kolichestvennyi, a ne kachestvennyi (na moi vzglyad). Esli ranee schitali, chto 2/3 zvezd dvoinye, to Lada govorit, chto 2/3 odinochnye. Te, kto v raschetah schitali, chto 1/2 zvezd dvoinye, mogut nichego v raschetah ne menyat'! Krome togo, odinochnost' yavlyaetsya v osnovnom svoistvom malomassivnyh zvezd (spektral'nye klassy K i pozdnee). Poskol'ku imenno eti zvezdy naibolee mnogochislenny, to otsyuda i sleduet vyvod o tom, chto bOl'shaya chast' zvezd v Galaktike odinochnye. Kstati skazat', tot fakt, chto dvoistvennost' menyaetsya dlya zvezd raznyh mass, dolzhen sushestvenno vliyat' na raschety metodom populyacionnogo sinteza dlya tesnyh dvoinyh sistem. Naskol'ko ya znayu, vse schitayut, chto dolya dvoinyh ne zavisit ot massy kompan'onov. Hotya obychno v raschetah interesuyutsya massivnymi sistemami (t.e. hotya by odin komponent dostatochno massiven, chtoby uspet' proevolyucionirovat' do kompaktnogo ostatka), a dlya takih sistem vse, vrode by, v poryadke (osobenno esli uchest', chto raspredelenie komponent po massam obychno prinimaetsya takim, chto naibolee veroyatny komponenty ravnyh mass).

Poluchennyi rezul'tat ochen' vazhen dlya teorii obrazovaniya zvezd (i planet).


astro-ph/0601440 Otkrytie blizhaishego korichnevogo karlika? (Discovery of the Closest Brown Dwarf to the Sun? A Methane Rich Brown Dwarf around the Nearby M8.5 Star SCR 1845-6357)
Authors: B.A. Biller, M. Kasper, L.M. Close, W. Brandner, S. Kellner
Comments: 5 pages, 3 figures. Submitted to the Astrophysical Journal. Some figures are currently omitted and will be supplied with the final, accepted version

V nachale - kur'ez. Pervyi raz ya vizhu, chtoby redaktory astro-ph propustili takoi glyuk, kak dvoinaya stat'ya: t.e. nomera 440 i 441 - eto odna i ta zhe rabota. Nadeyus', chto k sboyu v numeracii eto ne privedet.

Teper' o suti. Po dannym nablyudenii na VLT u blizkoi zvezdy SCR 1845-6357 (8.5 pk ot Solnca) obnaruzhen kompan'on. Pohozhe, chto eto korichnevyi (buryi) karlik. Poka, razumeetsya, ne ustanovlena fizicheskaya svyaz' zvezdy i karlika (t.e. ne isklyucheno, chto eto fonovyi ob'ekt), no skoree vsego eto real'naya para.


Vypusk 122. 11-23 dekabrya 2005

miniobzor astro-ph/0512436 Obrazovanie buryh karlikov (The formation of brown dwarfs)
Authors: A. P. Whitworth, S. P. Goodwin
Comments: 7 pages, 1 figure. To appear in Astron.Nachrichten. Includes an.cls file

Dan kratkii obzor mehanizmov obrazovaniya buryh (korichnevyh) karlikov. Takovyh naschityvaetsya chetyre: turbulentnaya fragmentaciya, gravitacionnaya neustoichivost' v diskah, vybros "zvezdnyh embrionov" iz yader, v kotoryh oni obrazuyutsya, i, nakonec, razrushenie izlucheniem (fotoerroziya) yader v oblastyah ionizovannogo vodoroda.


astro-ph/0512556 Rentgenovskie i opticheskie svoistva novyh ob'ektov tipa gamma Kassiopei, obnaruzhennyh v rentgenovskih obzorah (X-ray and optical properties of new Gamma Cas-like objects discovered in X-ray surveys)
Authors: Christian Motch, et al.
Comments: 7 pages, to appear in "Active OB Stars: Laboratories for Stellar & Circumstellar Physics", eds. S. Stefl, S. P. Owocki & A. Okazaki. ASP Conf. Ser. 2006, in press (uses asp style)

Gamma Kassiopei - izvestnaya yarkaya zvezda tipa Ve. T.e. eto massivnaya zvezda klassa V s emissionnymi liniyami v spektre. U nee obnaruzhen izbytok rentgenovskogo izlucheniya. Prichina mozhet byt' v nalichii kompan'ona, na kotoryi idet akkreciya. Samo po sebe eto ne udivitel'no, rentgenovskie sistemy s Ve-zvezdami sostavlyayut 2/3 vseh massivnyh rengenovskih dvoinyh (sm. katalog v astro-ph/0505275, setevaya versiya kataloga gotovitsya Natal'ei Raguzovoi). Odnako, esli vse eti sistemy sostoyat iz Ve-zvezdy i neitronnoi zvezdy, to gamma Kassiopei - yavno net. Vozmozhno, chto ee kompan'onom yavlyaetsya belyi karlik (ne isklyucheno i to, chto veter zvezdy imeet interesnye svoistva, privodyashie k izbytku rentgenovskogo izlucheniya; prichina mozhet kryt'sya v diske, sushestvuyushem vokrug bystro vrashayusheisya zvezdy).

Gamma Kassiopei - yarkii blizkii istochnik. Teper' s razvitiem tehniki rentgenovskih nablyudenii, nachali otkryvat' mnozhestvo istochnikov, pohozhih po svoim svoistvam na etu zvezdu. Sobstvenno, etomu i posvyashena stat'ya. Bolee detal'nye rezul'taty budut vskore predstavleny v polnoi zhurnal'noi publikacii, kotoraya, naskol'ko mne izvestno, uzhe prinyata v pechat'.


Vypusk 119. 29 oktyabrya - 11 noyabrya 2005

obzor astro-ph/0511176 Dvoinye kak astrofizicheskie laboratorii: obzor (Binaries as astrophysical laboratories: an overview)
Authors: Carla Maceroni
Comments: 13pages, 4 figures. Invited talk at ENEAS-PHD School on Variable Stars. Pecs (Hungary), September 2005

Kak izvestno, mnogie zvezdnye parametry (naprimer, massy) tochno mozhno izmerit' tol'ko dlya komponent dvoinyh. Imenno poetomu dvoinye sistemy mozhno nazvat' laboratoriyami astrofiziki, gde zvezdy odnovremenno yavlyayutsya i ob'ektom issledovaniya i testerom. V obzore summirovany osnovnye "eksperimenty", kotorye mozhno stavit' v takih laboratoriyah.


astro-ph/0511180 Astrobiologicheski interesnye zvezdy v 10 pk ot Solnca (Astrobiologically Interesting Stars within 10 parsecs of the Sun)
Authors: G.F. Porto de Mello et al.
Comments: 36 pages, recommended for publication in Astrobiology

Predstavlena svodka dannyh po blizkim zvezdam, predstavlyayushih interes s tochki zreniya poiska zhizni. Konechno, v pervuyu ochered' rech' idet o solnechnopodobnyh svetilah.


astro-ph/0511269 Odinochnye massivnye zvezdy pri kriticheskoi skorosti vrasheniya: vozmozhnaya svyaz' s Be i B[e] zvezdami (Single massive stars at the critical rotational velocity: possible links with Be and B[e] stars)
Authors: Georges Meynet, Andre Maeder
Comments: 11 pages, 13 figures, Stars with the B[e] phenomenon, M. Kraus and A. Miroshnichenko, ASP Conference Series, in press

Ve-zvezdy otlichayutsya emissionnymi liniyami, voznikayushimi iz-za ekvatorial'nogo istecheniya. Poslednee svyazano s chrezvychaino bystrym vrasheniem. Standartnyi scenarii govorit, chto takaya situaciya realizuetsya v osnovnom v tesnyh dvoinyh sistemah. T.e. raskrutka svyazana s vozdeistviem kompan'ona. V etoi zhe stat'e avtory (kstati, vedushie eksperty v oblasti zvednoi fiziki i evolyucii) pokazyvayut, chto korotkaya (okolo 10 000 let) stadiya Ve-zvezdy mozhet voznikat' i u odinochnyh zvezd. Zamechu, chto avtory v kachestve nachal'nogo usloviya uzhe berut dostatochno bystroe vrashenie. Krmoe togo, sdelany i drugie sushestvennye predpolozheniya. Tak chto rezul'tat model'no zavisim.


obzor astro-ph/0511273 Rentgenovskie populyacii v galaktikah (X-ray populations in galaxies)
Authors: G. Fabbiano
Comments: This is a review talk,to be published in the proceedings of the IAU Symposium 230, Populations of high energy sources in galaxies, held in Dublin (Ireland), August 15-19, 2005

Obzor posvyashen poslednim dannym po rentgenovskim istochnikam v gaalktikah. Chto my vidim? Celyi zoopark! Pri etom est' i mnoezhstvo zagadok. Daleko ne vse istochniki identificirovany. Vzyat', k primeru, ul'tramoshnye.

Otmechu takzhe i dva drugih svezhih obzora Fabbiano: astro-ph/0511273 i Investigating Galaxy Evolution with Chandra. Chemu posvyashen vtoroi yasno iz nazvaniya, a vot pervyi - eto epilog k simpoziumu MAS nomer 230. On soderzhit perechen' naibolee interesnyh rezul'tatov, dolozhennyh na nem.


astro-ph/0511321 HE 0437-5439 - gravitacionno nesvyazannaya giperskorostnaya V-zvezda glavnoi posledovatel'nosti (HE 0437-5439 -- an unbound hyper-velocity main-sequence B-type star)
Authors: Heinz Edelmann, Ralf Napiwotzki, Uli Heber, Norbert Christlieb, Dieter Reimers
Comments: 13 pages, 4 figures. Astrophysical Journal Letters, accepted

Avtory obnaruzhili interesnuyu zvezdu 16-i velichiny. Eto V-zvezda glavnoi posledovatel'nosti. Ee massa okolo 8 mass solnca. Nahoditsya ona v 61 kpk (!) ot nas. Kak ona tuda zabralas'? U nee ochen' bol'shaya skorost': bolee 700 km/s.

Est' dva sposoba tak razognat' zvezdu: analog gravitacionnogo manevra (v pole drugoi massivnoi zvezdy, ili, naprimer, v pole sverhmassivnoi chernoi dyry v centre galaktiki) i raspad tesnoi dvoinoi iz-za vzryva sverhnovoi. T.k. poka ne izvestno tochnoe napravlenie dvizheniya zvezdy, to ne yasno vyletela li ona iz central'noi oblasti nashei Galaktiki, ili zhe iz Bol'shogo Magellanovogo Oblaka. Esli iz Oblaka, to togda yasno, chto sverhmassivnaya chernaya dyra tut ni pri chem.

V drugoi stat'e (astro-ph/0511323) Hirsh i ego kollegi rasskazyvayut ob analogichnom otkrytii. Oni takzhe obnaruzhili v galo nashei Galaktiki zvezdu so skorost'yu (kak i vyshe rech' idet o skorosti otnositel'no Solnca) okolo 700 km/s. Dlya etoi zvezdy takzhe nuzhno prinyat' neobychnyi evolyucionnyi put' (sliyanie dvuh belyh karlikov, a zatem vybros za schet sverhmassivnoi chernoi dyry), t.k. esli by eto byla prosto obychnaya massivnaya zvezda, to posle vybrosa iz centra Galaktiki ona ne uspela by zabrat'sya tak daleko (19 kpk ot centra) za vremya svoei zhizni.


Vypusk 118. 17-28 oktyabrya 2005

obzor astro-ph/0510411 Novoe rassmotrenie i ocenka neopredelennostei v modelyah populyacionnogo sinteza (Revisiting and assessing uncertainties in stellar populations synthesis models)
Authors: M. Cervino, V. Luridiana
Comments: 35 pages, 16 figures. Invited review to "Resolved Stellar Populations", Cancun (Mexico) Apr 2005. To appear on the proceedings of the conference edited by D. Valls-Gabaud & M. Chavez, ASP Conf. Ser. (ASP: San Francisco)

Podrobno obsuzhdaetsya odin iz vazhnyh aspektov populyacionnyh modelei v astrofizike.


astro-ph/0510412 Zvezdy, obrazovannye v rezul'tate gravitacionnogo kollapsa, a ne akkrecii (Stars Form By Gravitational Collapse, Not Competitive Accretion)
Authors: Mark R. Krumholz et al.
Comments: Accepted for publication in Nature; 13 pages, no figures, Nature manuscript style

Avtory obsuzhdayut dve populyarnye na segodnyashnii den' modeli obrazovaniya zvezd. V pervoi vse proishodit tak. Molekulyarnye oblaka raspadayutsya na gazovye sgustki (yadra), kotorye zatem kollapsiruyut. Sootvetstvenno, massa sgustka opredelyaet massu zvezdy. Vo vtoroi iznachal'no obrazuyutsya yadra primerno odinakovogo razmera, a zatem ih massa uvelichivaetsya putem akkrecii. Sootvetstvenno burye (korichnevye) karliki ob'yasnyayutsya v takoi modeli vybrosom yadra do togo, kak ego massa sushestvenno vozrosla. V stat'e pokazano (a stat'ya-to, zamet'te, prinyata k publikacii v Nature!), chto v real'nyh oblastyah zvezdoobrazovaniya akkreciya budet nedostatochno sil'na. T.o., utverzhdayut avtory, imenno model' kollapsa "edinstvenno vernaya".


miniobzor astro-ph/0510416 Nablyudeniya solnechnopodobnyh oscillyacii: svezhie rezul'taty (Observing solar-like oscillations: recent results)
Authors: Timothy R. Bedding, Hans Kjeldsen
Comments: 6 pages, Invited review talk at the meeting on Stellar Pulsation and Evolution, June 2005, Rome. Proceedings to appear in "Memorie della Societa' Astronomica Italiana", Vol. 76/4, eds. A.R. Walker & G. Bono

Vot uzhe neskol'ko let kak astroseismologi aktivno i uspeshno izuchayut ne tol'ko Solnce, no i blizkie zvezdy. V stat'e predstavlen kratkii obzor poslednih dostizhenii, problem i planov astroseismologov.


astro-ph/0510581 Registraciya goryachego kompan'ona eta Karina (Detection of a Hot Binary Companion of $\eta$ Carinae)
Authors: Rosina C. Iping et al.
Comments: 13 pages with figures

To, chto izvestnaya zvezda eta Kilya (Carina) yavlyaetsya dvoinoi v principe izvestno dostatochno davno. Odnako do sih por ne udavalos' pryamo vydelit' izluchenie bolee slabogo komponenta.

S pomosh'yu sputnika FUSE (Far Ultraviolet Spectroscopic Explorer) udalos' vo vremya rentgenovskogo zatmeniya vydelit' spektr goryachego komponenta. Nesmotrya na to, chto komponent A dominiruet v optike, v dalekom ul'trafiolete pochti vse izluchenie svyazano s bolee goryachim kompan'onom V. Po parametram spektral'nyh linii udalos' postavit' nekotorye ogranichenie na parametry vtoroi zvezdy sistemy. V chastnosti, skorost' zvezdnogo vetra okazalas' v neskol'ko raz nizhe predskazyvavsheisya.


Vypusk 116. 11 sentyabrya - 30 sentyabrya 2005

obzor astro-ph/0509798 Obzor malomassivnyh zvezd i buryh karlikov (Review on low-mass stars and brown dwarfs)
Authors: G. Chabrier et al.
Comments: Invited review, "Resolved Stellar Populations", Cancun, april 2005

Eto teoreticheskii obzor, no vse ravno bez dannyh nablyudenii tut ne oboshlos'. Avtory v osnovnom rassmatrivayut uspehi i problemy v opisanii zvezd malyh mass. Tut i obrazovanie buryh karlikov i malomassivnyh zvezd, i teoriya ih stroeniya, i ih atmosfery, ....

Vazhnoe utverzhdenie avtorov sostoit v tom, chto razgranichenie mezhdu planetami i zvezdami dolzhno prohodit' ne po linii, za kotoroi vozmozhno gorenie deiteriya. Oni polagayut, chto "vodorazdel" svyazan s processami obrazovaniya nebesnyh tel (detali - v stat'e).


astro-ph/0509819 Katalog 1022 yarkih kontaktnyh dvoinyh sistem (A Catalog of 1022 Bright Contact Binary Stars)
Authors: S. J. Gettel, M. T. Geske, T. A. McKay
Comments: 26 pages, 12 figures, accepted for publication in AJ

Osobennost' kataloga v tom, chto on poluchen sistemoi ROTSE. Napomnyu, chto iznachal'no eta patrul'naya sistema prednaznachalas' dlya poiskov opticheskih tranzientov, soprovozhdayushih gamma-vspleski. No vspleski vse ne popadayutsya, a dannyh sistema sobiraet mnozhestvo. Poetomu pochti vse podobnye proekty nachinayut "pereprofilirovat'sya", stanovyatsya "mnogostanochnikami" i universalami. (Takaya zhe istoriya, naprimer, proishodit s rossiiskim proektom MASTER.) V samom dele, kazhduyu noch' (esli nebo yasnoe) sistemy otsnimayut vse nebo. Informacii more!!! Nado ee ispol'zovat'!

I vot - katalog kontaktnyh dvoinyh. Dlya postroeniya kataloga ispol'zovalis' takzhe dannye 2MASS (Two Micron All-Sky Survey). Dlya kazhdogo ob'ekta poluchena detal'naya krivaya bleska. Katalog pozvolil poluchit' novuyu ocenku prostranstvennoi plotnosti takih sistem: (1.7 +/- 0.6) x 10-5 pk-3.

Sm. takzhe stat'yu teh zhe avtorov astro-ph/0509820, gde opisany dannye sputnika ROSAT po etim ob'ektam.


Vypusk 115. 30 avgusta - 10 sentyabrya 2005

astro-ph/0508678 Diski i planety vokrug massivnyh belyh karlikov (Disks and Planets Around Massive White Dwarfs)
Authors: M. Livio et al.
Comments: 8 pages, 1 figure; accepted ApJL

Predskazyvaetsya, chto massivnye belye karliki dolzhny imet' pylevye diski i, vozmozhno, planety, sostoyashie iz uglekisloty. Dlya obnaruzheniya takih ob'ektov neobhodimy glubokie IK nablyudeniya.


Vypusk 113. 01-08 avgusta 2005

astro-ph/0508017 Avtomaticheskii obzor neba. Katalog peremennyh zvezd. V. (The All Sky Automated Survey. The Catalog of Variable Stars. V. Declinations 0 deg - 28 deg of the Northern Hemisphere)
Authors: G. Pojmanski, B. Pilecki, D. Szczygiel
Comments: 49 pages, 2 tables, appendix

Eto uzhe pyataya stat'ya v cikle, opisyvayushem katalog peremennyh zvezd, sozdayushiisya na osnove avtomaticheskogo obzora neba, provodimogo na nebol'shom instrumente. V stat'e dany rezul'taty po zvezdam, raspolozhennym mezhdu nebesnym ekvatorom i skoloneniem +28. Obnaruzhena peremennost' 11,509 zvezd yarche 15-i velichiny. Rezul'taty dostupny v Seti.


Vypusk 112. 22-31 iyulya 2005

astro-ph/0507523 Vozrast i massa praroditelya Siriusa V (The Age and Progenitor Mass of Sirius B)
Authors: James Liebert et al.
Comments: 12 pages, one figure (reduced resolution JPG posted), accepted for publication in the ApJ Letters

S pomosh'yu poslednih dannyh nablyudenii i programmy, modeliruyushei evolyuciyu zvezd, udalos' dostatochno tochno opredelit' massu zvezdy, iz kotoroi obrazovalas' Sirius V - belyi karlik v pare s Siriusom A, kotoryi my vidim kak yarchaishuyu zvezdu nochnogo neba. Massa okazalas' 4.78-5.43 mass Solnca, a prevrashenie v belyi karlik sostoyalos' primerno 115-135 millionov let nazad.


miniobzor astro-ph/0507582 Ukazaniya na fundamental'nyi predel massy zvezd po dannym o zvezdoobrazovanii v skopleniyah (Evidence for a fundamental stellar upper mass limit from clustered star formation, and some implications therof)
Authors: Pavel Kroupa, Carsten Weidner
Comments: 11 pages, invited review, to appear in Massive Star Birth, IAUSymp. 227, eds: R. Cesaroni et al

Ochen' interesnyi obzor, posvyashennyi probleme verhnego predela na massy zvezd. Ukazhem na odin nablyudatel'nyi fakt, obsuzhdaemyi v obzore. Nablyudeniya skoplenii ukazyvayut na predel v 150 mass Solnca vne zavisimosti ot metallichnosti skopleniya. Ob'yasnenii takomu udivitel'nomu faktu net.


astro-ph/0507593 Kollaps yader ochen' massivnyh zvezd (Core-Collapse Very Massive Stars: Evolution, Explosion, and Nucleosynthesis of Population III 500 -- 1000 $M_{\odot}$ Stars)
Authors: T. Ohkubo et al.
Comments: 46 pages, 45 figure files

Dany rezul'taty raschetov kollapsa massivnyh zvezd populyacii III. Eto ob'ekty s massoi do 1000 mass Solnca, prakticheski lishennye tyazhelyh elementov. Pokazano, chto samye massivnye iz nih mogut davat' chernye dyry s massami poryadka 500 solnechnyh.


astro-ph/0507687 "Nedostayushie" MZO v central'nom parseke Galaktiki: ukazaniya na zvezdoobrazovanie v massivnom akkrecionnom diske (The "missing" YSOs in the central parsec of the Galaxy: evidence for star formation in a massive accretion disk and a top-heavy IMF)
Authors: Sergei Nayakshin, Rashid Sunyaev
Comments: submitted to MNRAS, 5 pages, no figures

MZO - molodye zvezdnye ob'ekty. Stalo byt', rech' idet ob obrazovanii zvezd v centre nashei Galaktiki. Klyuchevoi vyvod avtorov sostoit v tom, chto oni polagayut MZO, obnaruzhennye vblizi Sgr A*, pervym pryamym primerom zvezdoobrazovaniya v massivnom diske, okruzhayushem sverhmassivnuyu chernuyu dyru.

O massivnyh zvezdnyh skopleniyah v central'noi oblasti Mlechnogo Puti mozhno prochest' v stat'e astro-ph/0507693.


Vypusk 111. 01-21 iyulya 2005

obzor astro-ph/0507130 Obrazovanie pervyh svetyashihsya ob'ektov (The Formation of Primordial Luminous Objects)
Authors: Emanuele Ripamonti, Tom Abel
Comments: 51 pages, 25 figures. Lecture notes for the spring 2003 SIGRAV Doctoral School "The Joint Evolution of Black Holes and Galaxies", to be published in: M.Colpi, V.Gorini, F. Haardt, U. Moschella (eds.), "Joint Evolution of Black Holes and Galaxies", series in High Energy Physics, Cosmology and Gravitation, Institute of Physics Publishing, Bristol and Philadelphia

Bol'shoi obzor (lekciya), posvyashennyi obrazovaniyu pervyh svetyashihsya ob'ektov vo vselennoi. T.e. rech' idet o massivnyh pervyh zvezdah, sostoyavshih iz legkih elementov. Oni obrazovalis' do poyavleniya pervyh galaktik i vnesli sushestvennyi vklad v obogashenie vselennoi tyazhelymi elementami.


astro-ph/0507343 Zvezdnaya evolyuciya s vrasheniem XIII: temp gamma-vspleskov na raznyh z (Stellar evolution with rotation XIII: Predicted GRB rates at various Z)
Authors: R. Hirschi, G. Meynet, A. Maeder
Comments: 16 pages, 14 figures, accepted by A&A

Kak uzhe ne raz rasskazyvalos' v Obzorah dlya rozhdeniya gamma-vspleska v standartnoi modeli neobhodimo, chtoby do obrazovaniya chernoi dyry yadro zvezdy dostatochno bystro vrashalos'. Raschety evolyucii zvezd s uchetom vrasheniya - trudnaya zadacha. V dannoi stat'e (13-i v serii) predstavleny raschety, pokazyvayushie, chto odinochnye zvezdy mogut imet' dostatochno bystrovrashayushiesya yadra (odnako, avtory prenebregayut po-krainei mere odnim vazhnym, no trudno uchityvaemym effektom). Sootvetstvenno, avtory pytayutsya rasschitat' temp gamma-vspleskov na raznyh krasnyh smesheniyah.


astro-ph/0507394 Identifikaciya krasnogo giganta, porodivshego sverhnovuyu 2005cs (Identification of the Red Supergiant Progenitor of Supernova 2005cs: Do the Progenitors of Type II-P Supernovae Have Low Mass?)
Authors: Weidong Li et al.
Comments: Submitted to ApJ

Udalos' opredelit' kakaya zvezda porodila sverhnovuyu v M51. Okazalos', chto eto krasnyi sverhgigant. Ocenka massy daet znachenie poryadka 7-9 mass Solnca (pered vzryvom). Eto ukazyvaet na to, chto sverhnovye tipa II s plato na krivoi bleska porozhdayutsya otnositel'no malomassivnymi zvezdami.


Vypusk 110. 15-30 iyunya 2005

astro-ph/0506311 Gl86B: belyi karlik vrashaetsya vokrug zvezdy s planetoi (Gl86B: a white dwarf orbits an exoplanet host star)
Authors: M. Mugrauer, R. Neuhaeuser
Comments: 5 pages, 5 figures, MNRAS letter

Vpervye udalos' obnaruzhit' chrezvychaino interesnuyu sistemu!

Neskol'ko let nazad bylo pokazano, chto zvezda Gl86 imeet planetu. Krome togo, na nebol'shom rasstoyanii byl obnaruzhen eshe odin ob'ekt, odnako bylo neyasno svyazan li on s Gl86 ili net. Avtoram etoi raboty udalos' pokazat', chto svyazan. Prichem eto ne obychnaya zvezda, a belyi karlik. T.o. teper' my znaem o sushestvovanii ekzoplanet v dvoinyh sistemah s belymi karlikami.


Vypusk 109. 01-14 iyunya 2005

astro-ph/0506052 Evolyuciya rentgenovskoi svetimosti molodyh zvezd (The evolution of X-ray emission in young stars)
Authors: Thomas Preibisch, Eric D. Feigelson
Comments: accepted for ApJS, COUP special issue

Kak izvestno, molodye zvezdy dostatochno aktivny v rentgenovskom diapazone. COUP (Chandra Orion Ultradeep Project) - eto programma glubokih rentgenovskih nablyudenii oblasti zvezdoobrazovaniya v Orione, provodimaya na sputnike Chandra. V ee ramkah avtory sobrali mnogo fakticheskogo materiala po rentgenovskomu izlucheniyu molodyh zvezd. V dannoi rabote provoditsya analiz etogo massiva dannyh.

Iz 481 zvezd v rentgene udalos' uvidet' pochti 100 procentov! Vidno umen'shenie rentgenovskoi aktivnosti s rostom vozrasta zvezd.


obzor astro-ph/0506161 Modeli zvezdnoi evolyucii: neopredelennosti i sistematika (Stellar evolutionary models: uncertainties and systematics)
Authors: S. Cassisi
Comments: 41 pages, 17 pages, invited review in "Resolved Stellar Populations", 2005, Cancun, Mexico

V obzore obsuzhdayutsya osnovnye neopredelennosti, prisushie modelyam evolyucii zvezd s massami ot 0.6 do 1.4 mass Solnca. Ved' nesmotrya na progress v raschetah struktury i evolyucii zvezd mnogoe ostaetsya nedostatochno horosho ponyatym.

Avtor rassmatrivaet osnovnye sostavlyayushie zvezdnyh modelei, poetomu obzor, nesmotrya na nekotorye tehnicheskie detali, mozhno porekomendovat' vsem dlya luchshego ponimaniya sovremennogo sostoyaniya zvezdnoi astrofiziki.


Vypusk 106. 01-10 maya 2005

astro-ph/0505019 109 novyh galakticheskih rasseyannyh skoplenii (109 new Galactic open clusters)
Authors: N.V. Kharchenko et al.
Comments: Fig.2 and Fig.3 available as 1013_ASCC_13.jpg and ncomp.jpg, respectively. In fact, during this search of new clusters in the catalogue ASCC-2.5, we discovered 130 clusters. It turned out that 21 of them are listed in the online list DLAM as private communications. We stress the point that this paper is the first presentation of these 21 clusters in a refereed publication. Accepted for publication in A&A

Privedeny dannye po sta s lishnim novym (t.e. tol'ko otkrytym) galakticheskim rasseyannym skopleniyam. Rezul'taty osnovany na obzore ASCC-2.5 (2.5 oznachaet 2.5 milliona zvezd).


astro-ph/0505032 Evolyucionnyi status Be zvezd (The Evolutionary Status of Be Stars: Results from a Photometric Study of Southern Open Clusters)
Authors: M. Virginia McSwain, Douglas R. Gies
Comments: 44 pages, submitted to ApJS

Be-zvezdy - eto massivnye (spektral'nyi klass V) zvezdy s emissionnymi liniyami. Linii voznikayut blagodarya istecheniyam s ekvatora zvezd. Istecheniya zhe poyavlyayutsya iz-za ochen' bystrogo vrasheniya. Prichiny etogo vrasheniya i rassmatrivayutsya v stat'e.

Prichin bystrogo vrasheniya mozhet byt' tri:

  • zvezdy rodilis' takimi
  • zvezdy byli raskrucheny akkreciei v dvoinoi
  • zvezdy raskrutilis' na odnom iz etapov svoei evolyucii na glavnoi posledovatel'nosti

    Avtory pokazyvayut, chto tert'ya prichina ne mozhet byt' sushestvennoi. Okolo 3/4 Be-zvezd raskrucheny v dvoinyh, a ostavshayasya chetvert' mozhet byt' svyazana s rozhdeniem bystrovrashayushihsya zvezd.


    Vypusk 105. 21-30 aprelya 2005

    astro-ph/0504483 Doveritel'nye intervaly modelei evolyucionnogo sinteza (Confidence limits of evolutionary synthesis models. IV An exact statistical formulation)
    Authors: M. Cervino, V. Luridiana, N. Cervino-Luridiana
    Comments: 20 pages, 8 figures, submitted to A&A.

    Migel' Chervin'o sdelal uzhe neskol'ko ochen' interesnyh rabot, posvyashennyh predelam primenimosti evolyucionnogo populyacionnogo sinteza. Kak vidno iz nazvaniya, eto chetvertaya rabota v serii. Rabota dostatochno tehnicheskaya, no na moi vzglyad vazhnaya.


    Vypusk 104. 11-20 aprelya 2005

    astro-ph/0504236 Avtomaticheskoe detektirovanie klassicheskih novyh s pomosh'yu neironnyh setei (Automated Detection of Classical Novae with Neural Networks)
    Authors: S. Feeney, V. Belokurov et al.
    Comments: 28 pages, 8 figures, The Astronomical Journal (in press)

    Neironnye seti mozhno "nauchit'" vydelyat' opredelennye tipy signalov. Eto ispol'zuetsya dlya vydeleniya razlichnyh tipov peremennyh zvezd i sobytii mikrolinzirovaniya v obzorah. V dannom sluchae rech' idet o testirovanii sistemy po poisku klassicheskih novyh. Ispol'zovany dannye kollaboracii POINT-AGAPE, kotoraya provodit poisk sobytii mikrolinzirovaniya v M31.

    Pokazano, chto sistema smogla chetko vydelit' 9 iz 13 izvestnyh novyh (ili dazhe 11, esli provesti dopolnitel'nyi analiz). Krome testov polucheny i original'nye rezul'taty. Vydeleno 19 novyh kandidatov v klassicheskie novye, prichem o 4 iz nih avtory govoryat kak ob ochen' horoshih kandidatah.


    astro-ph/0504341 Vspyshki normal'nyh zvezd. Nevernaya klassifikaciya FH Leo kak novopodobnoi peremennoi (Outbursts on normal stars. FH Leo misclassified as a novalike variable)
    Authors: T. H. Dall, L. Schmidtobreick, N. C. Santos, G. Israelian
    Comments: 8 pages, 7 figures. Accepted for publication in A&A

    Dvoinaya zvezda FH Leo byla klassificirovana kak novopodobnaya peremennaya. Etot vyvod osnovyvalsya na vspleske, zaregistrirovannom sputnikom Hipparcos. Odnako issledovaniya avtorov, kotorye poluchili spektry vysokogo razresheniya dlya dannoi sistemy, pokazyvayut, chto obe komponenty yavlyayutsya normal'nymi zvezdami pozdnih tipov (ot pozdnego F do rannego G).

    Esli v samom dele obe zvezdy yavlyayutsya normal'nymi, to nablyudavshiisya vsplesk stanovitsya zagadochnym yavleniem. Avtory rassmotreli neskol'ko variantov ob'yasneniya, no ne nashli ih udovletvoritel'nymi. Sootvetstvenno, oni predlagayut plany budushih issledovanii.


    Vypusk 103. 01-10 aprelya 2005

    astro-ph/0504086 Disk vokrug Vegi - Syurpriz so Spitcera (The Vega Debris Disk -- A Surprise from Spitzer)
    Authors: K. Y. L. Su et al.
    Comments: 13 pages, 17 figures, accepted for publication in ApJ. (Figures 2, 3a, 3b and 4 have been degraded to lower resolutions.)

    Kosmicheskii teleskop imeni Spitcera poluchil dostatochno detal'nye izobrazheniya oskolochnogo (debris) diska vokrug Vegi.


    Izobrazhenie na dline volny 70 mikrometrov

    Na dline volny 70 mikron (na risunke) disk imeet razmer 543 a.e. (70 uglovyh sekund). Na bolee korotkih dlinah on kompaktnee (330 a.e. na 24 mikronah), a na bolee dlinnyh - obshirnee (815 a.e. na 160 mikronah).


    astro-ph/0504175 Kakie zvezdy porozhdayut gamma-vspleski? (Which Massive stars are Gamma-Ray Burst Progenitors?)
    Authors: Jelena Petrovic et al.
    Comments: 40 pages

    V nastoyashee vremya naibolee populyarnaya teoriya t.n. "dlinnyh" gamma-vspleskov (napomnim, chto gamma-vspleski chetko delyatsya na dlinnye - bolee 10 sekund - i korotkie - poryadka sekundy i men'she) osnovyvaetsya na kollapse massivnoi zvezdy. Zvezda, po vsei vidimosti, prevrashaetsya v chernuyu dyru, vokrug kotoroi formiruetsya tor (aka bublik). Obrazuyutsya dzhety. V itoge, esli nam povezlo i dzhet napravlen na nas, my vidim gamma-vsplesk. Vstaet vopros: kakie zvezdy v konce svoego zhiznennogo puti porozhdayut vse eti interesneishie posledstviya?

    Dlya generacii gamma-vspleska neobhodimo, chtoby pered vzryvom yadro zvezdy dostatochno bystro vrashalos'. Rezul'taty raboty pokazyvayut, chto v bez ucheta vliyaniya magnitnogo polya neobhodimyi temp vrasheniya mozhet byt' dostignut. A vot prisutstvie polya vse portit.

    Avtory issleduyut evolyuciyu odinochnyh zvezd i zvezd, vhodyashih v dvoinye sistemy. Tam est' mnogo nereshennyh problem, poetomu avtory ne prihodyat k kakomu-libo odnoznachnomu vyvodu. Tak chto "mnogoe sdelano, no mnogoe eshe predstoit ..."


    Vypusk 101. 11-20 marta 2005

    astro-ph/0503243 Otkrytie magnitnyh polei goryachih subkarlikov (Discovery of magnetic fields in hot subdwarfs)
    Authors: S. J. O'Toole et al.
    Comments: 9 pages, 7 figures, A&A accepted

    Goryachie subkarliki lezhat v levoi verhnei chasti diagrammy Gercshprunga-Rassela neskol'ko nizhe i levee glavnoi posledovatel'nosti.

    S pomosh'yu teleskopa VLT provedeny polyarimetricheskie issledovaniya zvezd klassov sdB i sdO. Rezul'taty govoryat o polyah s napryazhennost'yu 1.5 tysyach Gauss.

    Otmetim, chto ranee uzhe soobshalos' o nablyudenii magnitnyh polei zvezd etogo tipa, naprimer, polya byli zaregistrirovany na 6-metrovom teleskope v SAO.


    Vypusk 100. 01-10 marta 2005

    astro-ph/0503050 Rentgenovskaya vspyshka Miry A (X-ray Outburst in Mira A)
    Authors: M. Karovska et al.
    Comments: 7 pages, 3 figures, to be published in the Astrophysical Journal Letters

    Izvestnaya peremennaya Mira (omikron) Kita yavlyaetsya simbioticheskoi sistemoi, sostoyashei iz krasnogo giganta (tochnee, zvezdy na asimptoticheskoi vetvi gigantov) i belogo karlika. Avtoram stat'i s pomosh'yu nablyudenii na sputnike Chandra vpervye udalos' zaregistrirovat' gigantskuyu rentgenovskuyu vspyshku ot Miry, a krome togo, udalos' vydelit' (razreshit') izobrazheniya kazhdoi iz zvezd pary.


    astro-ph/0503193 Verhnii predel na massu zvezd (An upper limit to the masses of stars)
    Authors: Donald F. Figer
    Comments: To appear in Nature, March 10, 2005, Vol. 34, No. 7030, 192 (ST ScI Eprint #1645). More files can be found at http://www.stsci.edu/~figer

    Skoplenie Arki mozhet soderzhat' ochen' massivnye zvezdy. Avtor stat'i pytaetsya ispol'zovat' eto obstoyatel'stvo dlya ustanovleniya verhnego predela na massu (razumeetsya, rech' idet o predele dlya metallichnosti, sootvetstvuyushei imeyusheisya v dannom skoplenii). Pokazano, chto v skoplenii net zvezd s nachal'noi massoi bolee 130 mass Solnca.

    Vypusk 98. 01-14 fevralya 2005

    astro-ph/0502042 Pul'siruyushie molodye burye karliki (Pulsating young brown dwarfs)
    Authors: Francesco Palla, Isabelle Baraffe
    Comments: 5 pages, 3 figures, A&A Letters (in press)

    Avtory postroili model' goreniya deiteriya v nedrah ochen' malomassivnyh zvezd i buryh (korichnevyh) karlikov. Obnaruzhena neustoichivost', kotoraya mozhet privodit' k pul'saciyam na vremenah poryadka neskol'kih chasov. Avtory obsuzhdayut vozmozhnost' togo, chto peremennost' nekotoryh zvezd etih tipov mozhet byt' svyazana imenno s pul'saciyami.


    astro-ph/0502043 Ostatochnoe proishozhdenie magnitnyh polei A-zvezd i belyh karlikov (A fossil origin for the magnetic fields of A-stars and white dwarfs)
    Authors: J. Braithwaite, H.C. Spruit
    Comments: Appeared in Nature, 431, 819 (2004)

    Est' zvezdy s anomal'no bol'shimi magnitnymi polyami. Eto, naprimer, Ap-zvezdy (k primeru, Aliot v kovshe Bol'shoi Medvedicy), nekotorye belye karliki i magnitary. Avtory ispol'zuyut chislennuyu model' dlya issledovaniya struktury magnitnogo polya vnutri sil'nozamagnichennyh ob'ektov. Pokazano, chto v sluchae Ap-zvezd pole imeet skoree ostatochnuyu (iskopaemuyu) prirodu, t.e. pole sohranilos' eshe so stadii formirovaniya zvezdy, a ne bylo tem ili inym sposobom usileno pozdnee.

    Avtory nashli konfiguraciyu polei, kotoraya mozhet sushestvovat' dostatochno dolgoe vremya. Oni polagayut, chto vo vseh treh perechislennyh vyshe tipah zvezd realizovana odna i ta zhe konfiguraciya polya.


    dissertaciya astro-ph/0502046 Zvezdy-praroditeli sverhnovyh s kollapsom yadra (Progenitors of Core-Collapse Supernovae)
    Authors: John J. Eldridge
    Comments: PhD Thesis, 171 pages, low detail figures, appendices removed to fit onto arXiv.org. For high resolution figures and the appendices goto http://www.iap.fr/users/eldridge/public.html

    Detal'no rassmotreny mnogie aspekty evolyucii zvezd, kotorye v konce svoei zhizni vzryvayutsya kak sverhnovye za schet kollapsa yadra.


    astro-ph/0502100 Otozhdestvlenie kosmicheskim teleskopom Spitcer samogo malomassivnogo korichnevogo karlika s okolozvezdnym diskom (Spitzer Identification of the Least Massive Known Brown Dwarf with a Circumstellar Disk)
    Authors: K. L. Luhman et al.
    Comments: 9 pages, 1 figure, The Astrophysical Journal Letters, 2005, 620, L51

    Nablyudeniya na kosmicheskom infrakrasnom teleskope Spitcer (Spitzer) pozvolili provesti detal'nye issledovaniya odnogo iz molodyh buryh (korichnevyh) karlikov v oblasti zvezdoobrazovaniya v sozvezdii Hameleona.

    Provedennoe modelirovanie pokazalo, chto eto samyi malomassivnyi korichnevyi karlik sredi teh, chto obladayut okolozvezdnymi diskami. Massa ob'ekta sostavlyaet vsego 15 mass Yupitera.

    Eto ochen' vazhnoe otkrytie, t.k. prolivaet svet na detali obrazovaniya odinochnyh malomassivnyh ob'ektov prakticheski vplot' do planetnyh mass.


    astro-ph/0502235 Poisk ochen' aktivnyh zvezd v Galaktike (A Search for Very Active Stars in the Galaxy)
    Authors: G. Tsarevsky et al.
    Comments: 13 pages

    K "Ochen' Aktivnym Zvezdam" avtory otnosyat ob'ekty s zhestkim rentgenovskim spektrom i aktivnost'yu v radiodiapazone. Eto dovol'no pestroe sobranie istochnikov raznyh tipov: ot eruptivnyh zvezd do mikrokvazarov.

    Proveden poisk vozmozhnyh kandidatov, ispol'zuya dannye sputnika ROSAT i radioteleskopov ATCA i VLA. Posle vyyavleniya 60 kandidatov nekotorye iz nih byli otnablyudeny v opticheskom diapazone. Opticheskie nablyudeniya pozvolili otozhdestvit' odin iz kandidatov kak tesnuyu dvoinuyu sistemy, odin kak aktivnoe galakticheskoe yadro (t.e. eto ne zvezdnyi ob'ekt, a fonovyi istochnik). Lyubopytny dva ob'ekta bez detalei v spektre. Dlya odnogo iz nih avtory obnaruzhili sobstvennoe dvizhenie. Oni predpolagayut, chto, vozmozhno, my imeem delo s novym tipom ob'ektov. (Otmetim, chto spektr bez detalei, "pohozhest'" na lacertidy i zametnoe sobstvennoe dvizhenie mogut ukazyvat' na to, chto ob'ekt yavlyaetsya odinochnoi neitronnoi zvezdoi).


    Vypusk 97. 17-31 yanvarya 2005

    astro-ph/0501462 Belye karliki v Omega Centavra (White Dwarfs in Omega Centauri: Preliminary Evidence)
    Authors: G. Bono et al.
    Comments: 6 pages

    Omega Centavra - samoe massivnoe sharovoe skoplenie v Galaktike. Ego aktivno nablyudayut v samyh raznyh diapazonah i s razlichnymi celyami. Avtory predstavlyayut pervye rezul'taty obrabotki dannyh, poluchennyh na Kosmicheskom teleskope. V fotometricheskii katalog vneseno bolee milliona zvezd.

    Pervaya zadacha, na kotoroi koncentriruyutsya avtory - obnaruzhenie belyh karlikov. Podcherknem, predstavleny predvaritel'nye rezul'taty, odnako uzhe rech' idet ob obnaruzhenii 600 istochnikov etogo tipa.


    astro-ph/0501548 Dinamicheskii metod opredeleniya mass zvezd s planetnymi tranzitami (A Dynamical Method for Measuring Masses of Stars with Transiting Planets)
    Authors: Abraham Loeb
    Comments: 4 pages, 2 figures, submitted to ApJL

    Predlagaetsya metod, v kotorom za schet prohozhdeniya planety po disku zvezdy budet vozmozhno opredelit' zvezdnuyu massu. Ocenki pokazyvayut, chto budushie missii tipa Kepler i COROT smogut dostich' chuvstvitel'nosti, dostatochnoi dlya obnaruzheniya effekta. Effekt zaklyuchaetsya v iskazhenii simmetrichnoi krivoi bleska vo vremya prohozhdeniya za schet uskoreniya planety.

    Kstati, podrobno o planetnyh tranzitah (prohozhdeniyah po disku zvezdy) mozhno prochest' v dissertacii astro-ph/0501558.


    astro-ph/0501647 Pochemu magnitnye polya ne mogut yavlyat'sya osnovnoi prichinoi, opredelyayushei formu planetarnyh tumannostei? (Why Magnetic Fields Cannot be the Main Agent Shaping Planetary Nebulae)
    Authors: Noam Soker
    Comments: Submitted to MNRAS

    Posle poyavleniya raboty nemeckih uchenyh, v kotoroi oni izmerili magnitnye polya central'nyh zvezd planetarnyh tumannostei (my pisali ob etom v proshlom vypuske) neizbezhno dolzhna byla nachat'sya diskussiya. Vot prevaya stat'ya.

    Avtor pytaetsya pokazat', chto magnitnye polya ne mogut otvechat' za bipolyarnuyu formu planetarnyh tumannostei. On polagaet, chto energii i uglovogo momenta budet nedostatochno dlya dostizheniya nablyudaemogo effekta. V kachestve al'ternativy rassmatrivaetsya dvoistvennost' sistemy (t.e. sfericheskaya simmetriya narushaetsya za schet prisutstviya vtoroi zvezdy).

    Sm. takzhe vtoruyu rabotu, gde rassuzhdeniya o dvoistvennosti sverhmassivnyh chernyh dyr prilagayutsya k formirovaniyu gigantskih polostei v skopleniyah galaktik.


    Vypusk 96. 01-16 yanvarya 2005

    astro-ph/0501040 Otkrytie magnitnyh polei central'nyh zvezd planetarnyh tumannostei (Discovery of magnetic fields in central stars of planetary nebulae)
    Authors: Stefan Jordan et al.
    Comments: 8 pages, 4 figures, Accepted for Publication by Astronomy & Astrophysics See also press release by A&A on their homepage www.edpsiences.org

    S pomosh'yu teleskopov VLT vpervye udalos' zaregistrirovat' magnitnye polya u central'nyh zvezd planetarnyh tumannostei! Sdelano eto pri pomoshi polyarimetricheskih nablyudenii. Vsego dannye polucheny dlya chetyreh ob'ektov. Polya sostavlyayut poryadka tysyach Gauss. Vazhno, chto vsego-to i bylo issledovano chetyre istochnika. T.e. dlya vseh ob'ektov v vyborke byl poluchen nenulevoi rezul'tat (hotya dlya dvuh zvezd dostovernost' izmerennyh polei ne velika). Vyskazyvaetsya gipoteza, chto polya budut tak ili inache zatuhat' pri perehode zvezdy so stadii yadra planetarnoi tumannosti k stadii belogo karlika. Osnovaniem dlya etoi gipotezy sluzhit maloe kolichestvo sil'no zamagnichennyh belyh karlikov (a pri sohranenii magnitnogo potoka pole karlika budet sushestvenno vyshe polya yadra planetarnoi tumannosti).

    Avtory obsuzhdayut, kak nablyudaemye polya mogut vliyat' na morfologiyu tumannosti. Oni polagayut, chto imenno magnitnoe pole otvetstvenno za bipolyarnuyu strukturu mnogih planetarnyh tumannostei.


    miniobzor astro-ph/0501049 Kak obrazuyutsya korichnevye karliki? (How do brown dwarves form?)
    Authors: Anthony P. Whitworth, Simon P. Goodwin
    Comments: To appear in the proceedings of "Low Mass Stars and Brown Dwarfs: IMF, Accretion and Activity" (Volterra, 2004). 6 pages, 1 figure

    Rassmotreny chetyre mehanizma obrazovaniya korichnevyh (buryh) karlikov: vybros zvezdnogo zarodysha iz formiruyushegosya yadra za schet dinamicheskogo vzaimodeistviya; fragmentaciya szhatogo sloya iz-za neprozrachnosti; gravitacionnye neustoichivosti v diskah, vyzvannye vzaimodeistviem s drugimi diskami; fotoeroziya (t.e. razrushenie izlucheniem) protozvezdnyh yader. Avtory polagayut, chto vazhno nabirat' statistiku po dvoistvennosti korichnevyh karlikov, a takzhe, chto nado detal'nee issledovat' diski vokrug etih ob'ektov.

    Takzhe sm. stat'yu The Decay of Accreting Triple Systems as Brown Dwarf Formation Scenario, gde opisan eshe odin mehanizm.


    astro-ph/0501177 Otkrytie nesvyazannoi giperskorostnoi zvezdy v galo Mlechnogo Puti (Discovery of an Unbound Hyper-Velocity Star in the Milky Way Halo)
    Authors: Warren R. Brown et al.
    Comments: 4 pages, submitted to ApJ Letters

    Otkryta zvezda, dvizhushayasya s ochen' vysokoi skorost'yu - okolo 800 km/s. Avtory polagayut, chto ona mogla byt' vybroshena iz central'noi oblasti Galaktiki za schet dinamicheskogo vzaimodeistviya.


    obzor astro-ph/0501226 Pul'sary v sharovyh skopleniyah (Pulsars in Globular Clusters)
    Authors: Fernando Camilo, Frederic A. Rasio
    Comments: Review included in proceedings of Aspen 2004 meeting "Binary Radio Pulsars"; 23 pages, 9 included EPS figures Journal-ref: ASP Conf. Ser. Vol. 328, 2005: Binary Radio Pulsars, eds. F. A. Rasio & I. H. Stairs (San Francisco: ASP), p. 147

    Bolee 100 radiopul'sarov obnaruzheno v 24 sharovyh skopleniyah (napominim, chto samih skoplenii gorazdo bol'she, prosto ne vo vseh poka (?) obnaruzhili radiopul'sary). Fakticheski vse pul'sary millisekundnye, t.e. "raskruchennye" akkreciei. Eto starye neitronnye zvezdy, period vrasheniya kotoryh byl umen'shen za schet uglovogo momenta veshestva, natyanutogo s kompan'ona v tesnoi dvoinoi sisteme.

    Pochti polovina izvestnyh radiopul'sarov v sharovyh skopleniyah nahoditsya v Terzan 5 i 47 Tukana. O skoplenii Terzan 5 est' otdel'naya svezhaya (dovol'no populyarnaya) stat'ya.


    Vypusk 95. 22-31 dekabrya 2004

    review astro-ph/0412333 Vzryvy klassicheskih novyh (Classical nova explosions)
    Authors: Margarita Hernanz (IEEC-CSIC)
    Comments: 14 pages

    Obzor sovremennogo sostoyaniya i rezul'tatov modelirovaniya vzryvov Novyh Zvezd. (Fenomen Novoi vyzyvaetsya termoyadernym vzryvom sloya veshestva na poverhnosti belogo karlika.) Osobyi upor sdelan na sleduyushie momenty:

    • kakie himicheskie elementy obrazuyutsya pri vzryvah, i kak eto zavisit ot parametrov belyh karlikov?
    • kak Novye obogashayut mezhzvezdnuyu sredu?
    • kakie ogranicheniya na modeli Novyh mogut nalozhit' gamma-nablyudeniya na sovremennyh ili ozhidaemyh v blizhaishem budushem sputnika?
    • kakie predpolozheniya pri modelirovanii Novyh yavlyayutsya naibolee kritichnymi?


    obzor astro-ph/0412543 Pyat'desyat let var'irovaniya nachal'noi funkcii mass: zvezdy promezhutochnyh mass (Fifty Years of IMF Variation: The Intermediate-Mass Stars)
    Authors: John Scalo
    Comments: 18 pages, including 4 figures: invited talk presented at the conference on "IMF@50: The Stellar Initial Mass Function Fifty Years Later" held at Abbazia di Spineto, Siena, Italy, May 2004; to be published by Kluwer Academic Publishers, edited by E. Corbelli, F. Palla, and H. Zinnecker

    Dzhon Skalo - odin iz vedushih specialistov po nachal'noi funkcii mass zvezd. V svoem obzore on rassuzhdaet o diapazone zvezdnyh mass ot 1 do primerno 10 mass Solnca. Osnovnoi vopros zaklyuchaetsya v sleduyushem: sushestvuet li dlya zvezd promezhutochnyh mass universal'naya funkciya mass (a vse otlichiya raznyh ocenok svyazany lish' s netochnostyami izmerenii), ili zhe razlichnye variacii funkcii imeyut pod soboi real'nye osnovaniya. Okonchatel'nogo otveta poka, k sozhaleniyu, net.


    astro-ph/0412622 Stolknoveniya zvezd i obrazovanie chernyh dyr v plotnyh zvezdnyh skopleniyah (Stellar Collisions and Black Hole Formation in Dense Star Clusters)
    Authors: Stephen McMillan, Simon Portegies Zwart
    Comments: 6 pages, 1 figure

    Tesnye prolety i lobovye stolknoveniya zvezd v plotnyh skopleniyah (sharovyh i skopleniyah vblizi centrov galaktik) privodyat k obrazovaniyu ochen' massivnyh zvezd, kotorye, posle bystroi termoyadernoi evolyucii, porozhdayut chernye dyry. Ob'ekty, obrazovavshiesya v rezul'tate sliyanii, obychno imeyut vysokuyu prostranstvennuyu skorost' ("ubegayushie zvezdy"). Vazhnye detali dannyh processov byli provereny metodom N-tel.

    V nebol'shih skopleniyah chislo slivayushihsya ob'ektov ogranichivaetsya prosto kolichestvom massivnyh zvezd, v bol'shih skopleniyah - chislom massivnyh zvezd v ih yadrah.


    Vypusk 94. 13-21 dekabrya 2004

    astro-ph/0412240 Otkrytie dvuh ochen' malomassivnyh dvoinyh (Discovery of Two Very Low-Mass Binaries: Final Results of an Adaptive Optics Survey of Nearby M6.0-M7.5 Stars)
    Authors: Nick Siegler et al.
    Comments: 20 pages, 8 figures, accepted to ApJ

    V rezul'tate issledovaniya 36 blizkih malomassivnyh zvezd pyat' iz nih byli razresheny na dva komponenta (dve sistemy opisany vpervye). Sistemy okazalis' dostatochno tesnymi. Dannyi rezul'tat podtverzhdaet, chto vo-pervyh, chem men'she massa komponent, tem men'she bol'shaya poluos' (v srednem, konechno), a vo-vtoryh, dolya dvoinyh sredi malomassivnyh zvezd men'she, chem sredi ih bolee massinyh sorodichei.


    miniobzor astro-ph/0412333 Vzryvy klassicheskih novyh (Classical nova explosions)
    Authors: Margarita Hernanz
    Comments: 14 pages, review paper for the conference 'The Astrophysics of Cataclysmic Variables and Related Objects', Strasbourg, France, 11-16 July 2004 (ASP Conference Series, Eds. J.M. Hameury and J.P. Lasota)

    Vse dostatochno horosho znayut, chto takoe novye zvezdy. Napomnim, tem ne menee, chto eto dvoinye sistemy s belymi karlikami, i vzryv proishodit imenno na poverhnosti karlika. V etom nebol'shom obzore opisany poslednie dostizheniya v izuchenii novyh. Osoboe vnimanie avtor udelyaet nukleosintezu, proishodyashemu vo vremya vspyshek.


    Vypusk 93. 01-12 dekabrya 2004

    astro-ph/0412008 Vklyuchenie dvoinyh sistem v evolyucionnyi populyacionnyi sintez (Inclusion of Binaries in Evolutionary Population Synthesis)
    Authors: Fenghui Zhang, Zhanwen Han, Lifang Li, Jarrod R. Hurley
    Comments: 18 pages, 17 figures, submitted to MNRAS

    Ne uspeli my zakonchit' nash obzor, posvyashennyi populyacionnomu sintezu, kak stali poyavlyat'sya novye interesnye raboty po etoi tematike. Pravda, na predydushuyu rabotu etoi gruppy my vse-taki ssylaemsya.

    Ne budem mnogo raspisyvat' pro metod populyacionnogo sinteza (zhedayushie mogut zaglyanut' v nash obzor, krome togo, my nadeemsya perevesti ego na russkii i vylozhit' na Astronete). Pereidem srazu k stat'e Zhanga i dr. Avtory uchityvayut vklad dvoinyh sistem v formirovanie integral'nyh spektrov galaktik (obychno takie raboty provodyatsya bez ucheta dvoistvennosti zvezd). Takzhe avtory uchityvayut razlichnye himicheskie sostavy zvezdnogo naseleniya.

    Vliyanie dvoinyh na integral'nye spektry okazyvaetsya sushestvennym. Odnako rezul'tat sushestvennym obrazom zavisit ot evolyucionnogo scenariya dlya dvoinyh sistem.


    miniobzor astro-ph/0412029 Sverhnovye i ih massivnye praroditeli (Supernovae and Their Massive Star Progenitors)
    Authors: Alexei V. Filippenko
    Comments: 10 pages, To be published in "The Fate of the Most Massive Stars," ed. R. M. Humphreys and K. Stanek (San Francisco: Astron. Society of the Pacific)

    Nebol'shoi nablyudatel'nyi obzor, posvyashennyi sverhnovym i ih praroditelyam. Dve osnovnye temy: poisk sverhnovyh i poisk zvezd-praroditelei do vzryva. Kratko ostanovimsya na vtorom punkte. Est' uzhe neskol'ko primerov, kogda na arhivnyh snimkah udavalos' rassmotret' zvezdy do vzryvov sverhnovyh. Naibolee izvestnyi primer - 1987A. Odnako est' i drugie. Eto chrezvychaino vazhnoe napravlenie issledovanii, t.k. bez tochnogo znanie svoistv vzryvayushihsya zvezd budet trudno (nevozmozhno?) postroit' teoriyu vzryvov.


    astro-ph/0412097 Zvezdy na habblovskom ul'traglubokom snimke (Stars in the Hubble Ultra Deep Field)
    Authors: N. Pirzka et al.
    Comments: 35 pages, 11 figures, accepted by ApJ

    Chego tol'ko net na glubokih snimkah Habbla! Konechno, pole bylo special'no vybrano tak, chtoby v osnovnom tuda popali vnegalakticheskie ob'ekty. Odnako popadayutsya i zvezdy.

    Avtory vnimatel'no issledovali snimok i vyyavili 46 slabyh istochnikov (zvezdnaya velichina do 29.5), kotorye mogut byt' zvezdami. Razumeetsya, eto vse krasnye ili belye karliki nashei Galaktiki. Kolichestvenno poiski avtorov mozhno summirovat' tak: obnaruzheno 18 zvezdnyh karlikov, dva buryh (korichnevyh) karlika i 4 belyh karlika (eti ob'ekty udalos' issledovat' spektral'no, poetomu avtory smogli uverenno opredelit' ih tip).

    Poluchennye dannye pomogayut luchshe ponyat' strukturu Galaktiki i dolyu zvezd raznyh tipov v nei. Naprimer, rezul'taty pokazyvayut, chto belye karliki ne mogut sostavlyat' bolee 10 procentov ot massy galakticheskogo galo.


    Vypusk 91. 01-14 noyabrya 2004

    astro-ph/0411179 SSSPM J1444-2019: ul'traholodnyi subkarlik s ochen' vysokim sobstvennym dvizheniem (SSSPM J1444-2019: an extremely high proper motion, ultracool subdwarf)
    Authors: R.-D. Scholz et al.
    Comments: 4 pages, 4 figures, accepted in A&A Lett.

    Otkryt novyi ob'ekt s predel'no vysokim sobstvennym dvizheniem (3.5"/god). On klassificirovan kak ul'traholodnyi subkarlik spektral'nogo tipa sdM9, no u nego takzhe vidny priznaki zvezd spektral'nogo klassa L: polnost'yu otsutstvuet polosa VO, predel'no sil'ny absorbcii TiO v opticheskom spektre. Luchevaya skorost' dannoi zvezdy sostavlyaet -160 km/s (t.e. ona priblizhaetsya k nam), rasstoyanie do nee ocenivaetsya v 16-24 pk, polnaya skorost' ob'ekta v geliocentricheskoi sisteme koordinat sostavlyaet

    (U,V,W)=(-244,-256,-100)+/-(32,77,6) km/s.
    Veroyatno, dannyi ob'ekt yavlyaetsya blizhaishei k Solncu zvezdoi galo Galaktiki.


    astro-ph/0411230 Dvoinye, dinamika skoplenii i populyacionnye issledovaniya zvezd i zvezdnyh fenomenov (Binaries, cluster dynamics and population studies of stars and stellar phenomena)
    Authors: D. Vanbeveren
    Comments: 8 pages, 1 figure

    Pered kazhdoi gruppoi, zanimayusheisya spektral'nym populyacionnym sintezom (dlya bol'shogo chisla odinochnyh zvezd s vysokoi tochnost'yu rasschityvaetsya ih evolyuciya ot momenta rozhdeniya do nastoyashego vremeni, a zatem summiruyutsya ih spektry v rezul'tate my imeet integral'nyi spektr galaktiki ili zvezdnogo skopleniya) v poslednie desyatiletiya vstaval vopros o tom kakoe vliyanie na ih rezul'taty, obladayushie vysokoi vnutrennei tochnost'yu, okazyvayut dvoinye zvezdy.

    V dannoi rabote rassmotreny sleduyushie voprosy: vliyanie dvoinyh na himicheskuyu evolyuciyu Galaktiki, na chastoty vspyshek sverhnovyh (razlichnyh tipov), na populyacii tochechnyh rentgenovskih istochnikov i nekotorye drugie voprosy.


    astro-ph/0411268 Dozhdi i oblaka v atmosferah buryh karlikov: svyazannye problemy ot malogo do bol'shogo (Rain and clouds in brown dwarf atmospheres: A coupled problem from small to large)
    Authors: Ch. Helling et al.
    Comments: 8 pages, 5 figures

    Krupnomasshtabnaya struktura atmosfer buryh karlikov opredelyaetsya celym ryadom vzaimodeistvuyushih processov: konvekciei, perenosom izlucheniya, obrazovaniem pyli i stratifikaciei veshestva v gravitacionnom pole. Sledstviem etih processov yavlyaetsya razdelenie himicheskih elementov s razlichnymi vesami.

    V rabote prodemonstrirovano, kak v atmosferah buryh karlikov mogut obrazovyvat'sya vpolne nablyudaemye pylevye oblaka.


    Vypusk 90. 25-31 oktyabrya 2004

    miniobzor astro-ph/0410684 Zvezdoobrazovanie i himicheskaya evolyuciya na bol'shih krasnyh smesheniyah (Star Formation and Chemical Evolution at High Redshift)
    Authors: Chip Kobulnicky
    Comments: 12 pages, 8 figures

    V etom obzore rassmotreny mehanizmy obogasheniya metallami v galaktikah na srednih i bol'shih krasnyh smesheniyah, vklyuchaya tempy zvezdoobrazovaniya, pogloshenie pyl'yu, kinematiku i himicheskih sostav mezhzvezdnoi sredy v galaktikah s moshnym zvezdoobrazovaniem. Na malyh krasnyh smesheniyah z=0-3 temp obogasheniya metallami sostavlyaet ΔZ/Δz=0.18-0.26 dex, chto gorazdo nizhe predskazyvaemogo kosmologicheskimi modelyami na bolee rannih etapah.


    obzor astro-ph/0410704 Struktura magnitovrashatel'nyh dzhetov i vetrov (The Structure of Magnetocentrifugal Jets and Winds I. Steady Mass Loading)
    Authors: Jeffrey M. Anderson, Zhi-Yun Li, Ruben Krasnopolsky and Roger D. Blandford
    Comments: 36 pages, including 19 figures, LaTeX, submitted to ApJ

    "Sceplenie" veshestva s magnitnym polem vrashayusheisya zvezdy porozhdaet magnitovrashatel'nye potoki veshestva razlichnoi stepeni kollimacii (uzkie - dzhety, shirokie - vetra). Dannyi obzor posvyashen rezul'tatam chislennogo modelirovaniya dannogo yavleniya na rasstoyaniyah ot 0.1 do 1AE ot central'noi zvezdy.


    Vypusk 89. 18-25 oktyabrya 2004

    miniobzor astro-ph/0410418 Litii v ochen' bednyh metallami zvezdah: problemy standartnogo pervichnogo nukleosinteza? (Lithium in Very Metal-poor Dwarf Stars - Problems for Standard Big Bang Nucleosynthesis?)
    Authors: David L. Lambert
    Comments: 18 pages, 5 figures

    Standartnyi scenarii pervichnogo nukleosinteza, parametry kotorogo vyvedeny iz nablyudenii anizotropii reliktovogo izlucheniya (po dannym WMAP) predskazyvaet opredelennoe obilie izotopov 6Li i 7Li. Pri etom obilie 7Li primerno na tri poryadka vyshe, chem nablyudaemoe v samyh bednyh metallami zvezdah, a obilie 6Li, naoborot, na tri poryadka nizhe, chem v etih zvezdah.

    V obzore obsuzhdaetsya vozmozhnost' razresheniya dannogo protivorechiya v ramkah standartnogo scenariya pervichnogo nukleosinteza.


    astro-ph/0410447 Blizhaishaya zvezda spektral'nogo klassa O3: komponent kratnoi sistemy HD150136 (The Nearest Star of spectral type O3: A Component of the Multiple System HD150136)
    Authors: V.S. Niemela, R.C. Gamen
    Comments: 7 pages, 4 figures, accepted for MNRAS

    Issledovanie vysokotochnyh (s bol'shim otnosheniem signal/shum) spektrov sistemy HD150136 pokazalo, chto samyi yarkii ee komponent imeet spektral'nyi klass O3. Po etim zhe spektram udalos' naiti vtoruyu sistemu peremeshayushihsya spektral'nyh linii i ustanovit' period odnoi iz komponent etoi kratnoi sistemy, ravnyi 2.6 dnyam (chto podtverdilo menee tochnye predvaritel'nye rezul'taty). Issledovanie otnositel'nyh amplitud linii He II, N V i N IV pozvolilo ocenit' massu zvezdy O3 sleduyushim obrazom: 18<M<27Mo.


    astro-ph/0410456 Simmetriya v izmeneniyah dzhetov SS433 i rasstoyanie do nego (Symmetry in the changing jets of SS433 and its true distance from us)
    Authors: K.Blundell, M.Bowler
    Comments: accepted by ApJ Letters

    Na serii glubokih radioizobrazhenii dzhetov SS433, poluchennyh v hode bolee chem dvuh precessionnyh ciklov (&gr;2x163 dnya), byli vyyavleny sistematicheskie otkloneniya parametrov dzhetov ot standartnoi kinematicheskoi modeli dlitel'nost'yu do desyati dnei. Prichem eti izmeneniya odinakovo proyavlyalis' v oboih dzhetah (s uchetom konechnoi skorosti rasprostraneniya fotonov). Sledstviem dannoi raboty yavlyaetsya nezavisimaya ocenka skorosti veshestva v dzhetah (ot 0.24 do 0.28 c) i takzhe nezavisimaya ocenka rasstoyaniya do SS 433 (5.5+/-0.2 kpk).

    Bolee podrobno skorost' veshestva v dzhetah SS433 rassmatrivaetsya v drugoi stat'e teh zhe avtorov: astro-ph/0410457.


    astro-ph/0410461 Variacii nachal'noi funkcii mass (Variation of the IMF)
    Authors: Pavel Kroupa, Carsten Weidner
    Comments: 13 pages, to appear in IMFat50: The Initial Mass Function 50 years later, ed: E. Corbelli, F. Palla, and H. Zinnecker, Kluwer Academic Publishers; a meeting held at the Abbazia di Spineto, Tuscany, Italy -- May 16-20, 2004

    Dovol'no interesnaya stat'ya ot odnogo iz avtoritetov v oblasti nachal'noi funkcii mass (NFM).

    Sut' sostoit v detal'nom obsuzhdenii razlichii mezhdu zvezdnoi NFM i galakticheskoi NFM.

    Pervaya universal'na. Ona sootvetstvuet gruppe zvezd, rozhdennoi v odnoi vspyshke zvezdoobrazovaniya (naprimer, v odnom skoplenii). Raznica mezhdu raznymi skopleniyami budet lish' v znachenii maksimal'noi massy: v malen'kih skopleniyah net zvezd bol'shoi massy.

    Vtoraya - galakticheskaya NFM - obrazuetsya putem slozheniya individual'nyh zvezdnyh. No! Poskol'ku dlya kazhdogo skopleniya est' verhnii predel massy zvezdy (zavisyashii ot massy samogo skopleniya), to summarnaya NFM ne budet takoi zhe kak individual'nye. Ona budet bolee krutoi (t.e. dolya malomassivnyh zvezd budet bol'she).

    Na vsyakii sluchai poyasnim eshe raz podhod avtorov. V malen'kih skopleniyah massivnyh zvezd net ne potomu, chto eto maloveroyatno, a prosto potomu, chto oni tam ne obrazuyutsya. (Poyasnim analogiei. Pisatel' s nebol'shim literaturnym darovaniem ne proizvodit shedevry rezhe, chem genial'nyi pisatel' - skazhem ne 1 iz 10, a 1 iz 100 knig - a prosto ne pishet shedevrov: est' potolok).

    T.o., rassuzhdayut avtory, sravnivat' NFM individual'nyh skoplenii s funkciyami mass galaktik nekorrektno, esli ne uchityvat' opisannogo vyshe effekta ukrucheniya NFM.

    Vtoroi vyvod mozhno sformulirovat' tak. Razlichiya v NFM mezhdu skopleniyami svyazany s razlichiem massy plyus effektom sluchainoi vyborki. Razlichiya zhe mezhdu galaktikami budut obuslovleny razlichiyami v tempe zvezdoobrazovaniya (chem vyshe temp, tem vyshe maksimal'naya massa skoplenii). Zametim, chto opyat' zhe spektr mass skoplenii mozhet byt' i universal'nym, i v igru vstupaet uzhe massa galaktiki....

    Eshe vazhnye zaklyucheniya.
    1. Temp sverhnovyh vtorogo tipa, rasschitannyi po standartnoi zvezdnoi NFM, okazyvaetsya zavyshennym, esli prilagat' ego ko vsei galaktike.
    2. Obogashenie galaktiki tyazhelymi elementami, rasschitannoe po zvezdnoi NFM, opyat' zhe zavysheno.


    Vypusk 88. 11-17 oktyabrya 2004

    astro-ph/0410226 Vozmozhnyi tretii komponent v sisteme dvuh korichnevyh karlikov DENIS-P J020529.0-115925 (A possible third component in the L dwarf binary system DENIS-P J020529.0-115925 discovered with the Hubble Space Telescope)
    Authors: H.Bouy et al.
    Comments: 15 pages, 3 tables, 6 figures, accepted for publication in AJ. High resolution version available at ftp://ftp.mpe.mpg.de/people/hbouy/publications/denis0205.ps.gz

    Vozmozhno obnaruzhena pervaya troinaya sistema korichnevyh (buryh) karlikov. Dva kompan'ona vidny absolyutno dostoverno, i est' podozreniya, chto odin iz nih takzhe dvoinoi.


    astro-ph/0410301 Rekonstrukciya evolyucii dvoinyh belyh karlikov: novyi zakon sblizheniya na stadii s obshei obolochkoi (Reconstructing the evolution of white dwarf binaries: further evidence for an alternative algorithm for the outcome of the common-envelope phase in close binaries)
    Authors: G. Nelemans and C.A. Tout
    Comments: 13 pages, 8 figures, accepted in MNRAS

    Kogda odna iz zvezd v tesnoi dvoinoi sisteme zapolnyaet svoyu polost' Rosha i po kakim-libo prichinam (naprimer, iz-za bol'shogo otnosheniya mass v sisteme) nachinaet peretekat' na vtoruyu komponentu v ochen' vysokom tempe, stol' vysokom, chto vtoraya zvezda ne uspevaet eto veshestvo prinimat', to vokrug sistemy mozhet obrazovat'sya obshaya obolochka. Na stadii s obshei obolochkoi komponenty dvoinoi sistemy ochen' sil'no sblizhayutsya (v desyatki raz za vremya vsego lish' v neskol'ko desyatkov tysyach let).

    Na neobhodimost' sushestvovaniya podobnogo processa dlya ob'yasneniya obrazovaniya osobo tesnyh dvoinyh sistem ukazal v 1976 godu Bogdan Pachin'skii. A v 1984 godu Vebbink (Webbink) pridumal opisyvayushuyu etot process energeticheskuyu (ili α) formulu

    ΔEenv = α x ΔEorb.
    Etoi formuloi pol'zuyutsya do sih por, hotya inogda ona ne ob'yasnyaet nablyudaemyh yavlenii.

    V dannoi rabote avtory predlozhili drugoi zakon, opisyvayushii sblizhenie zvezd na stadii s obshei obolochkoi. On osnovyvaetsya na zakone sohraneniya uglovogo momenta

    ΔJ/J = &gamma x ΔM/M.

    Avtory utverzhdayut, chto s pomosh'yu odnogo (dlya vseh sistem) koefficienta γ im udalos' opisat' vse nablyudaemye yavleniya.


    astro-ph/0410313 Seismologiya akkreciruyushih belyh karlikov (Seismology of Accreting White Dwarfs)
    Authors: Phil Arras, Dean Townsley, Lars Bildsten
    Comments: 6 pages, 2 figures.

    Pul'sacii akkreciruyushih belyh karlikov, vhodyashih v sostav nekotoryh kataklizmicheskih peremennyh, byli zaregistrirovany dostatochno nedavno (eto slozhnaya nablyudatel'naya zadacha). V principe, po takim kolebaniyam mozhno izuchat' vnutrennyuyu strukturu pul'siruyushih zvezd. No poka v etoi oblasti poluchen tol'ko odin rezul'tat: dlya sistemy GW Lib na osnove izucheniya ee pul'sacii polucheny ocenka massy belogo karlika (MWD=1.05Mo) i massy obolochki akkrecirovannogo veshestva (Menv=0.4x10-4 Mo).


    miniobzor astro-ph/0410317 Diagnostika diskov vokrug goryachih zvezd (Diagnostics of Disks Around Hot Stars)
    Authors: David H. Cohen et al.
    Comments: 14 pages with 8 figures.

    V stat'e obsuzhdayutsya tri sposoba obnaruzheniya diskov vokrug goryachih zvezd:

    1. po profilyam spektral'nyh linii;
    2. po polyarizacii otrazhennogo ot diska izlucheniya;
    3. i rentgenovskaya diagnostika, esli zvezda yavlyaetsya magnitnoi.


    astro-ph/0410331 Vozdeistvie massivnyh zvezd na nachal'nuyu funkciyu mass (Massive Star Feedback on the IMF)
    Authors: M. Robberto et al.
    Comments: 3 pages

    Avtory sdelali ochen' interesnoe nablyudenie. Oni zametili, chto temp akkrecii na formiruyushiesya zvezdy v skoplenii Trapeciya (v Orione) v srednem men'she, chem v associacii Telec-Voznichii. Interpretiruyut oni eto tak. Vozdeistvie izlucheniya uzhe sformirovavshihsya massivnyh zvezd privodit k umen'sheniyu akkrecii, naprimer, iz-za ispareniya diskov. T.o. v bogatyh skopleniyah dolya malomassivnyh zvezd i buryh (korichnevyh) karlikov mozhet byt' men'she.


    Vypusk 87. 01-10 oktyabrya 2004

    obzor astro-ph/0410024 Vliyanie dvoinyh na galakticheskuyu himicheskuyu evolyuciya (The influence of binaries on galactic chemical evolution)
    Authors: Erwin De Donder, Dany Vanbeveren
    Comments: 115 pages, many figures and tables, New Astronomy Reviews 2004, 48, 861-975

    Imenno tak: 115 stranic, mnogo risunkov i tablic. Bol'shoi obzor po himicheskoi evolyucii Galaktiki.
    Hotya! Sam obzor na astro-ph nedostupen! Ego nado ili skachivat' iz New Astronomy (esli dostup est'), ili zaprashivat' u avtorov (ili potihonechku skachat' otsyuda).

    Zato mozhno pochitat' bolee korotkuyu stat'yu Vanbeveren'a astro-ph/0410021, posvyashennuyu izbrannym voprosam evolyucii massivnyh zvezd.


    astro-ph/0410044 Kakaya protozvezda samaya molodaya? (Which are the youngest protostars? Determining properties of confirmed and candidate Class0 sources by broad-band photometry)
    Authors: Dirk Froebrich
    Comments: 21 pages, 2 figures, 4 tables, accepted by ApJS

    Na osnove vseh opublikovannyh nablyudenii na dlinah voln ot 1 mikrona do 3.5 mm sostavlen spisok 95 podtverzhdennyh kandidatov v ob'ekty "Klassa 0" (predel'no molodye protozvezdy).

    Bolee podrobnye dannye, po sravneniyu s privedennymi v stat'e, mozhno naiti na saite avtorov http://www.dias.ie/protostars.


    miniobzor astro-ph/0410046 Obrazovanie i evolyuciya zvezd ochen' malyh mass i buryh karlikov (Formation and Evolution of Very Low Mass Stars and Brown Dwarfs)
    Authors: Jochen Eisloeffel et al.
    Comments: 6 pages, 2 figures

    Mnogo li mozhno rasskazat' v dvuh stat'yah po pyat' stranic? Okazyvaetsya - Da.

    Obrazovanie i evolyuciya buryh (korichnevyh) karlikov - "goryachaya tema" v issledovanii zvezd v poslednie gody. V dannom obzore rassmotreny takie voprosy, kak poslednie nablyudeniya diskov, akkreciya, istecheniya, prostranstvennoe raspredelenie i dvoistvennost' buryh karlikov.

    Vtoraya stat'ya (astro-ph/0410047) posvyashena skorosti evolyucii vrasheniya dannyh ob'ektov.


    astro-ph/0410053 Pochemu net dzhetov u kataklizmicheskih peremennyh? (Why there are no jets from cataclysmic variable stars)
    Authors: Jean-Pierre Lasota, Noam Soker
    Comments: 6 pages

    Avtory obrashayut vnimanie na to, chto teplovaya model' formirovaniya dzhetov, razrabotannaya dlya protozvezdnyh ob'ektov okruzhennyh diskom, prekrasno podhodit i dlya kataklizmicheskih peremennyh: dvoinyh zvezd v kotoryh prisutstvuet belyi karlik okruzhennyi akkrecionnym diskom. Primenenie teplovoi modeli k etomu novomu tipu sistem pozvolyaet estestvennym obrazom otvetit' na vopros pochemu u nih otsutstvuyut dzhety. Prichinoi etogo okazyvaetsya otnositel'naya slabost' vliyaniya magnitnyh polei na disk v kataklizmicheskih peremennyh.


    astro-ph/0410136 Ul'traglubokii proekt Chandra-Orion: nablyudeniya i spisok istochnikov (Chandra Orion Ultradeep Project: Observations and Source Lists)
    Authors: K. V. Getman et al.
    Comments: 2 pages, 11 figures, 12 tables. Accepted for publication in ApJS, special issue dedicated to Chandra Orion Ultradeep Project. A version with high quality figures can be found at http://www.astro.psu.edu/users/gkosta/COUP_Methodology.pdf

    Rentgenovskii kosmicheskii teleskop Chandra poluchil ochen' glubokoe izobrazhenie oblasti skopleniya Tumannosti Oriona. Pochti million sekund (838 ks) - eto bolee nedeli! Eto naibolee bogatyi odnorodnyi material po rentgenovskomu izobrazheniyu normal'nyh zvezd: katalog vklyuchaet bolee 1600 istochnikov.


    Vypusk 86. 20-30 sentyabrya 2004

    astro-ph/0409577 Pyl' ot sverhnovoi v dalekom kvazare (A supernova origin for dust in a high-redshift quasar)
    Authors: R. Maiolino et al.
    Comments: To Appear in Nature, September 30, 2004

    Kak izvestno, uzhe na bol'shih krasnyh smesheniyah nablyudaetsya prakticheski solnechnyi himicheskii sostav veshestva. Krome togo nablyudaetsya i mezhzvezdnaya pyl'. Proishozhdenie ee do konca ne yasno, odnako naibolee ochevidnym kandidatom yavlyayutsya sverhnovye (drugoi variant - pozdnie stadii evolyucii zvezd).

    Maiolino i dr. issledovali spektr kvazara na krasnom smeshenii z=6.2. Nablyudeniya provodilis' v IK diapazone na ital'yanskom teleskope im. Galileya.

    Obrabotka dannyh pokazala, chto nablyudaemoe pogloshenie prekrasno opisyvaetsya modelyami, v kotoryh pyl' porozhdaetsya sverhnovymi tipa II, t.e. vzryvami massivnyh zvezd.


    miniobzor astro-ph/0409722 Vrashenie i peremeshivanie v massivnyh zvezdah: principy i neopredelennosti (Rotation and Mixing in Massive Stars: Principles and Uncertainties)
    Authors: Georges Meynet and Andre Maeder
    Comments: 12 pages, 4 figures.

    Vrashenie zvezdy vyzyvaet celyi ryad neustoichivostei v ee nedrah. Pri etom izmenyaetsya perenos uglovogo momenta, hod termoyadernyh reakcii, diffuziya razlichnyh himicheskih elementov.

    V obzore iz pervyh principov vyvodyatsya i rassmatrivayutsya sootvetstvuyushie uravneniya evolyucii. Podrobno razbiraetsya model' bystro vrashayusheisya zvezdy s massoi 9Mo, ekvatorial'noi skorost'yu vrasheniya 290 km/s i solnechnym himicheskim sostavom.


    obzor astro-ph/0409737 Obrazovanie pervyh zvezd vo Vselennoi (The Formation of the First Stars in the Universe)
    Authors: Simon C.O. Glover
    Comments: 74 pages, 4 figures, accepted for Space Science Reviews

    Etot obzor posvyashen voprosam obrazovaniya pervyh zvezd. Osoboe vnimenie v nem udeleno trem sleduyushim problemam:

    • obrazovanie pervyh protogalaktik i ostyvanie gaza vnutri nih;
    • fragmentaciya oblakov ostyvayushego gaza;
    • sfericheskaya i diskovaya akkreciya okruzhayushego veshestva na protozvezdy.
    V kazhdoi iz tem rassmotreny naibolee interesnye rezul'taty poslednih let.


    katalog astro-ph/0409750 Katalog molodyh zvezdnyh sverhskoplenii v galaktike so vspyshkoi zvezdoobrazovaniya M82 (Young Super Star Clusters in the Starburst of M82: The Catalogue)
    Authors: V. P. Melo et al.
    Comments: 45 pages, 5 figures, 12 tables. Accepted for ApJ

    Nedavnie nablyudeniya s Habblovskogo teleskopa pokazali, chto oblasti vspyshek zvezdoobrazovaniya v galaktikah predstavlyayut soboi bol'shoe chislo kompaktnyh molodyh zvezdnyh skoplenii. V dannoi rabote predstavlen fotometricheskii katalog podobnyh skoplenii dlya galaktiki s ochen' intensivnym zvezdoobrazovaniem M82. V kataloge privedeny 197 molodyh zvezdnyh sverhskoplenii (grupp kompaktnyh skoplenii) v etoi galaktike. Iz nablyudeniya velis' v linii Hα i v chetyreh shirokih opticheskih fil'trah. Razmery skoplenii lezhat v intervale ot 3 do 9 pk, a ih massy - ot 104 do 106Mo.


    Vypusk 85. 13-19 sentyabrya 2004

    astro-ph/0409235 Astrometricheskoe otkrytie GJ 164B (Astrometric Discovery of GJ 164B)
    Authors: Steven H. Pravdo et al
    Comments: 14 pages, 6 figs

    Malomassivnyi komponent u karlika GJ 164 spektral'nogo klassa M byl otkryt s pomosh'yu astrometricheskih izmerenii na PZS kamere Zvezdnogo Planetnogo Obzora. Komponent poluchil oboznachenie GJ 164B. Poskol'ku parallaks etoi sistemy izvesten (0.082+/-0.008"), udalos' vychislit' parametry ee orbity: P=2.04+/-0.03 goda, a=1.03+/-0.03AE, summarnaya massa sistemy M=0.265+/-0.020Mo. Massy komponent, sootvetstvenno, MA=0.170+/-0.015Mo i MB=0.095+/-0.015Mo. Na osnove etih dannyh novyi komponent otnesen k zvezdam so spektral'nym klassom M6-8V.


    astro-ph/0409246 Differencial'noe vrashenie F-zvezd glavnoi posledovatel'nosti (Differential rotation of main sequence F stars)
    Authors: M. Kueker, G. Ruediger
    Comments: 7 pages, 10 figures

    Proizveden raschet differencial'no vrashayusheisya zvezdy nulevogo vozrasta (tol'ko chto vyshedshei na glavnuyu posledovatel'nost') s massoi 1.2Mo (spektral'nogo klassa F8). Samosoglasovannyi profil' differencial'nogo vrasheniya poluchilsya ochen' pohozhim na Solnechnyi. Maksimal'naya raznost' skorostei vrasheniya (na ekvatore i polyuse) dostigalas' pri periode 7 dnei, t.e. pri medlennom vrashenii.


    astro-ph/0409362 Rasstoyanie do Pleyad: blizkie infrakrasnye spektry zvezd glavnoi posledovatel'nosti (The distance to the Pleiades: Main sequence fitting in the near infrared)
    Authors: S.M. Percival et al.
    Comments: 8 pages. A&A accepted

    Astrometricheskii eksperiment Gipparhos ocenil rasstoyanie do Pleyad v 118 pk. Eto na 10% men'she "klassicheskih" ocenok na osnove podgonki spektrov zvezd glavnoi posledovatel'nosti v etoi gruppe. Chem mozhet byt' vyzvano podobnoe rashozhdenie? Avtora proveli vysokotochnoe sravnenie teoreticheskih i nablyudaemyh spektrov zvezd Pleyad v blizkom IK-diapazone i poluchili ocenku rasstoyaniya 133.8+/-3 pk. Sledovatel'no, eto rezul'taty Gipparhosa imeyut 10% tochnost'.


    miniobzor astro-ph/0409389 Spektral'naya klassifikaciya posle M (Spectral Classification Beyond M)
    Authors: S.K.Leggett et al.
    Comments: 12 pages including 17 figures

    Uzhe okolo 10 let posle zvezd klassa M, kotorymi ran'she vse konchalos', idet klass L (infrakrasnye zvezdy), a za nim klass T (korichnevye karliki). Segodnya izvestno uzhe mnogo ob'ektov etih klassov. V obzore rassmotreny modeli atmosfer etih ob'ektov i na etoi osnove opisyvayutsya ih spektral'nye svoistva.


    obzor astro-ph/0409407 Datirovka vozrasta galaktik so zvezdoobrazovaniem (Age-Dating of Starburst Galaxies)
    Authors: Claus Leitherer
    Comments: 16 pages, 6 figures. Invited review talk. To be published in "The Evolution of Starbursts", ed. S. Huettemeister & E. Manthey (Melville: AIP)

    Daetsya obzor metodov opredeleniya vozrastov zvezdnyh populyacii posle vspyshke zvezdoobrazovaniya.


    Vypusk 84. 01-12 sentyabrya 2004

    miniobzor astro-ph/0409096 Poyas Gulda, zvezdoobrazovanie i lokal'naya mezhzvezdnaya sreda (The Gould Belt, star formation, and the local interstellar medium)
    Authors: Isabelle A. Grenier
    Comments: 10 pages, 4 figures

    Istoriya lokal'noi mezhzvezdnoi sredy i lokal'nogo (zhe) zvezdoobrazovaniya na rasstoyanii do neskol'kih sot parsek i za period v neskol'ko desyatkov millionov let pochti polnost'yu opredelyaetsya poyasom Gulda. Avtor rassmatrivaet pochti vse: zony HI i H2, obrazovanie obychnyh i massivnyh zvezd, a iz poslednih - rentgenovskih istochnikov.


    Vypusk 83. 01-31 avgusta 2004

    astro-ph/0408240 Solnechnye okrestnosti: novye blizkie zvezdy na yuzhnom nebe (The Solar Neighborhood X: New Nearby Stars in the Southern Sky and Accurate Photometric Distance Estimates for Red Dwarfs)
    Authors: Todd J. Henry et al.
    Comments: 8 pages, accepted to ApJ

    Rech' idet o sleduyushih zvezdah: SCR 1845-6357 (spektral'nyi klass M8.5V, rasstoyanie 4.6 pk), dvoinaya sistema SCR 0630-7643AB (M6.0VJ, 7.0 pk) i SCR 1138-7721 (M5.0V, 9.4 pk). Abbreviatura SCR oboznachaet SuperCOSMOS RECONS fotometricheskii obzor, v ramkah kotorogo oni byli obnaruzheny.


    astro-ph/0408320 Evolyuciya naibolee massivnyh zvezd (Evolution of the Most Massive Stars)
    Authors: Andre Maeder er al.
    Comments: 10 pages, 8 figures

    V stat'e obsuzhdaetsya evolyuciya deistvitel'no naibolee massivnyh zvezd, s massami okolo 100Mo i vyshe, dlya kotoryh dostigaetsya tak nazyvaemyi ΩΓ-predel, kogda zvezda perestaet byt' gravitacionno-svyazannoi iz-za vysokogo davleniya izlucheniya i bystrogo vrasheniya. Vozmozhno, takie ochen' massivnye zvezdy svyazany s gamma-vspleskami.


    astro-ph/0408364 Metod kristallov: astroseismologiya BPM 37093 (The Crystal Method: Asteroseismology of BPM 37093)
    Authors: T.S. Metcalfe, M.H. Montgomery, A. Kanaan
    Comments: 6 pages, 4 figures

    Bolee 40 let proshlo s momenta vyhoda stat'i Eda Salpitera i soavtorov v kotoroi oni predskazali, chto v uglerodnyh i kislorodnyh yadrah naibolee holodnyh belyh karlikov mozhet obrazovyvat'sya kristallicheskaya reshetka. Odin iz vozmozhnyh variantov obnaruzheniya takih "kristallov": po pul'saciyam karlikov. Vpervye pul'sacii dostatochno holodnogo, potencial'no kristallizovannogo, belogo karlika BPM 37093, byli zaregistrirovany v 1992 godu. V 1999 godu sushestvovanie u etoi zvezdy kristallicheskogo yadra bylo dokazano. Ostal'noe v zametke.


    obzor astro-ph/0408491 10 glavnyh problem fiziki massivnyh zvezd (Top 10 Problems on Massive Stars)
    Authors: Cassio Barbosa, Donald Figer
    Comments: 21 pages, 11 lists, 107 problems!

    Avtory posledovatel'no rassmotreli vse evolyucionnye stadii massivnyh zvezd i otmetili 107(!) sovsem ili do konca ne reshennyh problem teorii evolyucii etih ob'ektov. I, konechno, byla vydelena desyatka vazhneishih.


    astro-ph/0408561 Priroda peremennogo istochnika IRS16SW v galakticheskom centre (The Nature of the Variable Galactic Center Source IRS16SW)
    Authors: D.L.DePoy et al.
    Comments: 11 pages, 2 figures. Accepted by ApJ

    IRS16SW - yarkaya peremennaya zvezda, no krivaya ee bleska ne sovpadaet ni s krivymi zatmennyh dvoinyh, ni s krivymi bleska drugih peremennyh zvezd. Mozhet byt' IRS16SW otnositsya k teoreticheski predskazannym, no do sih por eshe ne otkrytym peremennym zvezdam ochen' bol'shoi massy.


    Vypusk 82. 01-31 iyulya 2004

    obzor astro-ph/0407459 Evolyuciya massivnyh zvezd do okonchaniya goreniya kisloroda v centre (Evolution of Massive Stars Up to the End of Central Oxygen Burning)
    Authors: Mounib F. El Eid, Bradley S. Meyer and Lih-Sin The
    Comments: 46 pages, 15 figures. To be published in ApJ vol 611, August 10, 2004

    Poslednie rezul'taty raschetov evolyucii massivnyh zvezd (setka mass 15, 20, 25 i 30 Mo dlya solnechnogo himsostava. Raschety provedeny do ochen' pozdnih stadii evolyucii - do polnogo vygoraniya v centre zvezdy kisloroda. Drugie detali raschetov - v samom obzore.


    Vypusk 81. 20-30 iyunya 2004

    astro-ph/0406411 Samye massivnye zvezdy v Mestnoi gruppe: tochnoe izmerenie mass zvezd v zatmennyh dvoinyh (The Most Massive Stars in the Local Group: Measuring Accurate Masses of Stars in Eclipsing Binaries)
    Authors: Alceste Z. Bonanos, Krzysztof Z. Stanek
    Comments: Invited contribution, to appear in "Fate of the Most Massive Stars", R. M. Humphreys and K. Z. Stanek, eds, ASP Conference Series

    Tochnye izmereniya mass zvezd vozmozhny tol'ko v dvoinyh sistemah. Prichem, dazhe v sluchae dvoinoi mozhet byt' odin vazhnyi neopredelennyi parametr - naklon orbity k luchu zreniya. Situaciya uproshaetsya v zatmennyh dvoinyh: tam my nahodimsya v ploskosti orbity. Imenno takie sistemy dayut naibolee tochnye izmereniya mass.

    V dannoi stat'e avtory opisyvayut izmereniya mass naibolee tyazhelyh zvezd, tochnee teh massivnyh zvezd, dlya kotoryh polucheny tochnye dannye. Poka rekordsmenami yavlyayutsya dve zvezdy s massami bolee 80 mass Solnca.


    astro-ph/0406573 SB9: Devyatyi katalog orbit spektral'nyh dvoinyh (SB9: The Ninth Catalogue of Spectroscopic Binary Orbits)
    Authors: D.Pourbaix, A.A. Tokovinin et al.
    Comments: 6 pages, 6 figures, acceptev in A&A

    Orbity dvoinyh sistem chashe vsego opredelyayut dvumya sposobami: dlya shirokih vizual'nyh dvoinyh - po izmeneniyu rasstoyaniya i polozheniya razdelennyh komponentov, dlya tesnyh spektral'nyh dvoinyh - po doplerovskomu sdvigu spektral'nyh linii komponentov sistemy.

    Stal dostupnym devyatyi katalog orbit spektral'nyh dvoinyh, v nem privedeny dannye o 2386 dvoinyh zvezdah.


    Raspredelenie spektral'nyh dvoinyh po periodam (v dnyah):
    tolstaya liniya - sistemy s odnim spektrom, tonkaya - s dvumya.


    Vypusk 80. (01) - 12-20 iyunya 2004

    astro-ph/0406274 Bolee informativnaya kartinka Habblovskogo glubokogo snimka (A more informative picture of the HST Ultra Deep Field)
    Authors: Nicholas Wherry, Michael R. Blanton, David W. Hogg
    Comments: 3 pages, astro-ph only. If the PS file doesn't properly display (because of a strange arxiv bug), try the PDF version. Code and full resolution JPEG available at http://cosmo.nyu.edu/hogg/visualization/

    Avtory pereobrabotali glubokii Habblovskii snimok. Sut' zaklyuchalas' v tom, chtoby popytat'sya sozdat' izobrazhenie, sposobnoe na real'nyh ustroistvah (monitory, printery) peredat' shirokii dinamicheskii diapazon ishodnyh cvetov. Kak pishut avtory, osobenno zametno uluchshenie izobrazhenii yarkih ob'ektov (naprimer, central'nye oblasti yarkih galaktik). Vidny gradient cvetov v galaktikah, spiral'naya struktura i t.p. Central'nye oblasti yarkih ellipticheskih galaktik vyglyadyat ne belymi, a krasnymi. Krome togo, dlya izobrazheniya dalekih galaktik (s zametnym krasnym smesheniem) byla ispol'zovana drugaya palitra.

    Detali mozhno naiti v rabote avtorov Lupton et al 2004, PASP, 116, 133--137. Samu programmu obrabotki mozhno skachat'.



    obzor astro-ph/0406319 Astrofizicheskie dzhety i istecheniya (Astrophysical Jets and Outflows)
    Authors: Elisabete M. de Gouveia Dal Pino
    Comments: pdf file, 20 pages, 12 figures

    Obzor posvyashennyi astrofizicheskim dzhetam (v osnovnom gidrodinamicheskim, v otlichie ot predydushei stat'i astro-ph/0406319). V obzore rassmotreny sleduyushie temy: nablyudaemyi svoistva dzhetov YSO (molodyh zvezdnyh ob'ektov), AGN, mikrokvazarov, teoriya, chislennoe modelirovanie, priroda "uzlov" v dzhetah, rasprostranenie dzhetov, ih precessiya, tormozhenie, vzaimodeistvie so sredoi, "nakonechniki" dzhetov (struktury na ih dal'nih koncah), vliyanie magnitnyh polei, relyativistskie dzhety, mehanizmy kollimacii i, nakonec, nereshennye voprosy.


    miniobzor astro-ph/0406373 Raschety nelineinyh zvezdnyh pul'sacii: Zvezdy RR Lyrae (Automated Nonlinear Stellar Pulsation Calculations: Applications to RR Lyrae stars. The Slope of the Fundamental Blue Edge and the First RRd Model Survey)
    Authors: R. Szabo et al.
    Comments: 13 pages, 6 figures, accepted in A&A

    V dannoi stat'e opisana metodologiya raschetov pul'sacii zvezd i izmeneniya ih povedeniya vdol' evolyucionnyh trekov.


    Vypusk 79. 01-11 iyunya 2004

    astro-ph/0406017 Dlitel'naya istoriya zvezdoobrazovaniya v Omega Centavra (The extended star formation history of omega Centauri)
    Authors: Michael Hilker et al.
    Comments: 4 pages, 3 figures, accepted for publication in Astronomy & Astrophysics (Letters)

    Poyavilos' dve interesnye korotkie zametki, posvyashennye samomu bol'shomu v Galaktike sharovomu skopleniyu Omega Centavra. V pervoi rabote rasskazyvaetsya o tom, kak po izmereniyam metallichnosti zvezd udalos' opredelit' prodolzhitel'nost' zvezdoobrazovaniya v etom skoplenii. Razbros zvezdnyh vozrastov okazalsya poryadka 3 milliardov let. Eto mnogo. Avtoram ne udalos' opredelit' svyazan li razbros s nepreryvnym zvezdoobrazovaniem v techenie etogo vremeni, ili zhe eto lish' pereryv mezhdu dvumya epizodami zvezdoobrazovaniya. Proyasnenie etogo voprosa budet predmetov budushei raboty.


    astro-ph/0406076 Dvoinaya glavnaya posledovatel'nost' v Omega Centavra (The double main sequence of Omega Centauri)
    Authors: L. R. Bedin et al.
    Comments: 4 pages, 2 figures, Mem.S.A.It., Milano, 19-23 April 2004, in press

    Vtoraya rabota posvyashena detal'nomu issledovaniyu raspredeleniya zvezd Omega Centavra na diagramme Gercshprunga-Rassela. Po dannym kosmicheskogo teleskopa udalos' rassmotret', chto glavnaya posledovatel'nost' dvoinaya. Krome togo, obnaruzheny dopolnitel'nye vetvi subgigantov.

    V svete predydushei raboty mozhno pospekulirovat', chto vse-taki bylo neskol'ko epizodov zvezdoobrazovaniya. Prichem metallichnost' novoobrazuyushihsya zvezd byla razlichnoi, otsyuda i sdvigi na diagramme Gercshpunga-Rassela.


    Vypusk 78. 13-31 maya 2004

    astro-ph/0405348 Proishozhdenie massivnyh O-zvezd polya: chast' I. Poisk skoplenii (The Origin of Massive O-type Field Stars. Part I: A Search for Clusters)
    Authors: W.J. de Wit, L. Testi, F. Palla, L. Vanzi, H. Zinnecker
    Comments: 22 pages, accepted for publication in A&A

    Bolee-menee vse znayut, chto molodye massivnye zvezdy nablyudayutsya v sostave skoplenii/associacii (mozhno dazhe vspomnit' starodavnyuyu gipotezu Ambarcumyana, kotoraya hot' i byla neverna, no privela ko mnogim interesnym rezul'tatam). Odnako okolo 20 procentov O-zvezd vse-taki nablyudayut "v pole", t.e. vne skoplenii.

    Avtory proveli poisk vozmozhnyh slabyh skoplenii vokrug takih zvezd. Dlya podavlyayushei chasti rassmotrennyh ob'ektov rezul'tat okazalsya otricatel'nym: skoplenii net. Tem ne menee eto ne oznachaet, chto eti massivnye zvezdy voznikali po odinochke. Zvezdy mogli byt' vybrosheny iz skoplenii. Detal'nomu rassmotreniyu etogo voprosa budet posvyashena otdel'naya rabota avtorov.


    Vypusk 77. 01-12 maya 2004

    astro-ph/0405054 Net planet vokrug HD 219542 B (No Planet Around HD 219542 B)
    Authors: S.Desidera et al.
    Comments: 4 pages, 4 figures, A&A Letters

    V 2003 godu u zvezdy HD 219542 B byli obnaruzheny nebol'shie periodicheskie variacii luchevoi skorosti, chto pozvolilo predpolozhit' sushestvovanie u nee planety s massoi kak u Saturna. Uvy, prodolzhenie nablyudenii v konce 2003 i v 2004 godu pokazalo, chto nablyudaemye variacii skoree vsego svyazany s sobstvennoi aktivnost'yu zvezdy.

    Byvaet i tak.


    miniobzor astro-ph/0405064 Massa, vozrast i prostranstvennoe raspredelenie zvezdnyh skoplenii (Mass, Age, and Space Distributions of Star Clusters)
    Authors: S. Michael Fall
    Comments: 10 pages, 3 figures; latex, uses asp2004.sty. To appear in Formation and Evolution of Massive Young Star Clusters, eds. H.J.G.L.M. Lamers, A. Nota, & L.J. Smith (ASP, San Francisco), 2004

    Avtor daet obzor po rezul'tatam issledovanii zvezdnyh skoplenii vo vzaimodeistvuyushih galaktikah Antenny. Zametka ponyatnaya i interesnaya. Vydelim iz nee lish' odin syuzhet.

    Okazyvaetsya, raspredelenie skoplenii po vozrastam vo mnogom opredelyaetsya tempom razrusheniya etih ob'ektov. Delo v tom, chto oni dovol'no slabo svyazany gravitacionno. Poetomu dazhe odna massivnaya zvezda za korotkuyu svoyu zhizn' mozhet uspet' "vydut'" iz skopleniya dostatochnuyu massu mezhzvezdnoi sredy, chtoby sistema stala gravitacionno nesvyazannoi.

    Takzhe vyskazhem korotkuyu ideyu. Ranee my pisali o rabotah Migelya Chervino, v chastnosti o rabote Statistical Synthesis Models. V nei avtory pokazali, chto v malomassivnyh skopleniyah odna naibolee yarkaya zvezda mozhet dominirovat' v obshem spektre, i chto eto sushestvenno dlya interpretacii dannyh i dlya modelirovaniya. Razumno predpolozhit', chto tochno takzhe odna zvezda mozhet dominirovat' v processe razrusheniya skopleniya za schet vymetaniya veshestva. Takaya situaciya budet privodit' k tomu, chto na malyh massah skoplenii v raspredelenii chisla ot vozrasta budut sushestvennye fluktuacii. S odnoi storony, skoplenie mozhet vyzhit', esli v rezul'tate fluktuacii v nem ne poyavilis' dostatochno massivnye zvezdy, s drugoi - sluchainoe poyavlenie neskol'kih massivnyh zvezd mozhet razrushit' skoplenie, kotoroe "v srednem" dolzhno bylo by zhit' dol'she.


    astro-ph/0405111 Pervoe dinamicheskoe opredelenie massy dvoinogo L-karlika (First determination of the dynamical mass of a binary L dwarf)
    Authors: H. Bouy et al.
    Comments: 16 pages, 7 figures, 6 tables

    V klassicheskom ryadu spektral'nyh klassov zvezd O-B-A-F-G-K-M klassa L ne bylo. On poyavilsya s sozdaniem novogo pokoleniya infrakrasnyh priemnikov izlucheniya i sootvetstvuyushih teleskopov. Eto samye malen'kie (po masse i po razmeru), samye tusklye i samye holodnye zvezdy. Do sih por ih massy ocenivalis' putem sravneniya s teoreticheskimi modelyami spektrov ili drugimi kosvennymi putyami. No vot poyavilos' pervoe dinamicheskoe izmerenie massy klassicheskim sposobom: po nablyudeniyu komponent dvoinoi sistemy. Nablyudalsya dvoinoi L-karlik 2MASSW J0746425+2000321. Nablyudeniya velis' na Habblovskom teleskope i na VLT v techenii neskol'kih let. Spektral'nye klassy i massy komponent okazalis' sleduyushimi:

    N Sp.klass Massa [Mo]
    1L0+/-0.50.085+/-0.010
    2L1.5+/-0.50.066+/-0.006


    astro-ph/0405127 Al'tair: Samaya yarkaya zvezda tipa δ Shita (Altair: The Brightest Delta Scuti Star)
    Authors: D.L. Buzasi et al.
    Comments: 15 pages, 5 figures, 2 tables

    Al'tair (α Orla; α Aql) po svoim fizicheskim parametram lezhit vnutri polosy pul'sacionnoi neustoichivosti, kotoraya vyzyvaet kolebaniya zvezd tipa δ Shita. Odnako, do sih por nikakie pul'sacii u Al'taira ne nablyudalis'. Novye nablyudeniya, s ispol'zovaniem zvezdoi kamery Wide-Field Infrared Explorer'a pokazali, chto pul'sacii vse taki est', tol'ko ih amplituda ochen' nevelika i sostavlyaet vsego okolo 0.001 zvezdnoi velichiny. Bolee togo, v spektre pul'sacii Al'taira udalos' s uverennost'yu vydelit' prisutstvie po krainei mere sem' razlichnyh mod kolebanii.

    Krivaya bleska Al'taira: sploshnaya liniya - model'naya fur'e approksimaciya. Amplituda bleska dana v tysyachnyh dolyah zvezdnoi velichiny, shkala vremeni - v sutkah.


    Vypusk 75. 12-19 aprelya 2004

    astro-ph/0404223 Otkrytie v optike treh rasseyannyh skoplenii v Galaktike (Discovery of three optical open clusters in the Galaxy)
    Authors: E.Bica et al.
    Comments: 12 pages, 9 figures

    Po opticheskim nablyudeniyam otkryto tri novyh rasseyannyh skopleniya v nashei Galaktike: dva v sozvezdii Shita (pervoe s koordinatami l=18.44o i b=-0.42o, vtoroe - l=19.60o i b=-1.02o) i odno v Bol'shoi Medvedice (l=235.61o i b=-4.10o). Vozrasta etih skoplenii ocenivayutsya v 25, 500 i 32-100 mln.let, a rasstoyaniya do nih 1.6, 2.2 i 3.9 kpk, sootvetstvenno.

    Fotografii treh otkrytyh rasseyannyh skoplenii


    Vypusk 74. 01-11 aprelya 2004

    astro-ph/0404004 Fotonnye puzyri v molodyh massivnyh zvezdah (Photon Bubbles in Young Massive Stars)
    Authors: N.J.Turner et al.
    Comments: 4 pages, 3 figures

    Tot fakt, chto v goryachih massivnyh zvezdah osnovnoi vklad v davlenie daet izluchenie, davno i horosho izvesten. No ran'she schitalos', chto fotony raspredeleny vnutri gaza ravnomerno. Odnako poslednie spektroskopicheskie issledovaniya, provedennye v dannoi stat'e, pokazyvayut chto gaz v fotosferah goryachih molodyh O-zvezd dvizhetsya so skorost'yu okolo ili vyshe skorosti zvuka. Etot fakt mozhno ob'yasnit', esli predpolozhit, chto izluchenie obrazuet vnutri fotosfery "puzyr'ki" fotonnogo gaza.


    astro-ph/0404012 Tumannost' MakNeila v Orione: istoriya aktivnosti (Mc Neil's Nebula in Orion: The Outburst History)
    Authors: C.Briceno et al.
    Comments: 13 pages, 4 figures, accepted to ApJ Letters

    Tumannost' MakNeila yavilas' ochen' interesnym otkrytiem zimy etogo goda. Deistvitel'no, lyubitel' astronomii pryamo ryadom s superizvestnoi Tumannost'yu Oriona otkryl novyi ob'ekt! Eshe v sentyabre 2003 g. nikakoi tumannosti tam ne bylo, i vot ....

    V stat'e avtory predstavlyayut rezul'taty nablyudenii tumannosti na metrovom shmidtovskom teleskope v Venesuele. Ryad dannyh ohvatyvaet 5-letnii period. Nachalo vspyshki avtory datiruyut mezhdu 28 oktyabrya i 15 noyabrya 2003 g. Obsuzhdaetsya vozmozhnost' togo, chto v sluchae etoi tumannosti my imeem delo s fuorom (istochnikom tipa FU Ori).


    miniobzor astro-ph/0404016 Klassicheskie zvezdy T Tauri kak istochniki vidimyh v optike istechenii s parsekovymi masshtabami (Classical T Tauri stars as sources of parsec-scale optical outflows)
    Authors: F. McGroarty and T.P. Ray
    Comments: 13 pages, 11 figures, URL

    Nebol'shoi obzor klassicheskih molodyh zvezd, eshe ne vyshedshih na glavnuyu posledovatel'nost', kakimi yavlyayutsya T Tau. Osnovnoi upor delaetsya na istecheniya veshestva iz etih ob'ektov. V obzore predstavleny podrobnye svedeniya o strukturah vokrug pyati konkretnyh ob'ektov: CW Tau, DG Tau, DO Tau, HV Tau C i RW Aur. V stat'e dany izobrazheniya s ochen' nizkim kachestvom, prilichnye (no bol'shie) fotografii privedeny na saite avtorov: www.dias.ie.


    astro-ph/0404049 Novye blizkie zvezdy iz Liverpul'-Edingburskogo obzora zvezd s vysokimi sobstvennymi dvizheniyami (New nearby stars in the Liverpool-Edinburgh high proper motion survey selected by DENIS photometry)
    Authors: C. Reyle, A. C. Robin
    Comments: 8 pages, 4 figures, accepted in A&A

    Prodolzhaetsya poisk zvezd s vysokimi sobstvennymi dvizheniyami, provodimyi uchenymi iz universitetov Liperpulya i Edinburga. Ochen' vysokoe sobstvennoe dvizhenie ob'ektov, naidennyh v dannom obzore, chashe vsego ob'yasnyaetsya ih blizost'yu k Solncu. O predvaritel'nyh rezul'tatah etogo obzora my pisali okolo goda nazad. Za eto vremya naideno eshe 100 zvezd udalennyh ot nas na rasstoyanie men'shee 25 parsek. Vse oni yavlyayutsya zvezdami spektral'nogo klassa M ili belymi karlikami. 10 zvezd iz etoi gruppy lezhat na rasstoyanii 15 parsek ili blizhe.


    astro-ph/0404070 Dve programmy dlya izucheniya evolyucii zvezd i yadernoi astrofiziki (Two programs for studying stellar evolution and nuclear astrophysics)
    Authors: Theodore Liolios
    Comments: 9 RevTex pages, 8 figures.

    Eta stat'ya opisyvaet dve programmy na FORTRAN'e, kotorye pozvolyayut stroit' diagrammy Gercshprunga-Rassela i evolyucionnye treki otdel'nyh zvezd na nei. Programma pozvolyaet zadavat' takie parametry "risuemoi" zvezdy, kak himsostav (central'nyi i fotosfernyi), svetimost', effektivnuyu temperaturu, radius fotosfery i massu zvezdy. Sami programmy dostatochno prosty, no snabzheny ochen' bol'shim naborom failov s dannymi. A za grafiku otvechaet horosho izvestnyi svobodno rasprostranyaemy paket programm PGPLOT.


    Vypusk 73. 16-31 marta 2004

    obzor astro-ph/0403319 Slabye peremennye ob'ekty, otkrytye pri sravnenii katalogov POSS i SDSS (Variable Faint Optical Sources Discovered by Comparing POSS and SDSS Catalogs)
    Authors: B.Sesar et al.
    Comments: 59 pages, 26 figures, submitted to AJ

    POSS (Palomar Observatory Sky Survey) - opticheskii katalog (fotometricheskii i astrometricheskii) vsego neba, povtoryayushii znamenityi Palomarskii obzor. Sostoit iz dvuh chastei (ili dvuh ocheredei): POSS I i POSS II.

    SDSS (Sloan Digital Sky Survey) - prodolzhayushiisya fotometricheskii i spektral'nyi(!) obzor primerno 1/4 neba, v osnovnom v napravlenii galakticheskih polyusov. (Sloan - familiya osnovatelya fonda, finansiruyushego provedenie dannogo obzora.) Podrobnee ob etom kataloge sm. astro-ph/0403325.

    Bylo provedeno sravnenie iz oblastei ploshad'yu 2000 kv.grad iz katalogov POSS i 1-i ocheredi SDSS. V rezul'tate etoi raboty vydeleno ~60000 peremennyh ob'ektov. Zametnymi sostavlyayushimi etoi gruppy yavlyayutsya kvazary i peremennye tipa RR Liry. Dlya kvazarov podtverzhdeno harakternoe vremya peremennosti poryadka 1 goda, dlya zvezd tipa RR Liry pokazano, chto oni otslezhivayut strukturu galo Galaktiki. (Eto, konechno, predvaritel'nye rezul'taty.)


    astro-ph/0403329 Akkreciya vetra v dvoinyh sistemah - I. (Wind accretion in binary stars - I. Mass accretion ratio)
    Authors: T.Nagae et al.
    Comments: 8 pages, accepted in Astron. Astroph.

    Esli zvezda v tesnoi dvoinoi sisteme ne zapolnyaet polost' Rosha, no blizka k etomu, i, odnovremenno, obladaet moshnym zvezdnym vetrom, to akkreciya mozhet byt' dostatochno moshnoi, a ee fizika - ochen' interesnoi.

    V dannoi rabote privedeny rezul'taty trehmernogo gidrodinamicheskogo modelirovaniya, provedennye gruppoi yaponskih issledovatelei. Tehnicheskaya storona (sobstvenno samo chislennoe modelirovanie) v stat'e rassmotrena ochen' kratko, zato mnogo graficheskih illyustracii. Osoboe vnimanie avtory udelyayut voprosu kachestvennomu razlichiyu struktury potokov pri akkrecii iz vetra (sil'noe nedozapolnenie polosti Rosha), pri techenii cherez tochku Lagranzha (polost' Rosha zapolnena) i v promezhutochnyh sluchayah (maloe otklonenie ot polosti Rosha).

    Sleva tipichnaya geometriya potoka pri akkrecii iz zvezdnogo vetra,
    sprava - pri zapolnenii polosti Rosha.


    astro-ph/0403337 Struktura i evolyuciya malomassivnyh sistem tipa W UMa (Structure and evolution of low mass W UMa type systems)
    Authors: Lifang Li, Zhanwen Han, Fenghui Zhang
    Comments: 12 pages, 10 figures, to be published in MNRAS

    Sistemy tipa W UMa (W Bol'shoi Medvedicy - po nazvaniyu peremennoi zvezdy -prototipa dannogo klassa zvezd) predstavlyayut soboi ochen' tesnye dvoinye zvezdy. Oba komponenta sistem etogo tipa nahodyatsya na glavnoi posledovatel'nosti i oba zapolnyayut svoi polosti Rosha. Veshestvo v takih sistemah peretekaet ot bolee massivnoi zvezdy k menee massivnoi, no eto "v srednem" na ochen' bol'shih intervalah vremeni, a na korotkih intervalah process nosit gorazdo bolee slozhnyh ciklicheskii harakter. Polnoi teorii evolyucii sistem dannogo tipa do sih por net. V dannoi stat'e privedeno dostatochno detal'noe rassmotrenie sovremennogo sostoyaniya etoi problemy.


    Vypusk 72. 01-15 marta 2004

    obzor astro-ph/0403306 Vekovaya evolyuciya kompaktnyh dvoinyh s uchetom irradiacii (Long-term evolution of compact binaries with irradiation feedback)
    Authors: A. Buning and H. Ritter
    Comments: 19 pages, 24 figures, accepted by A&A

    V malomassivnyh tesnyh polurazdelennyh dvoinyh sistemah s odnim kompaktnym komponentom ochen' sushestvenny processy irradiacii - oblucheniya normal'no zvezdy (donora) izlucheniem, voznikayushim v processe akkrecii veshestva na kompaktnyi ob'ekt. Izluchenie, padayushee na poverhnost' normal'noi komponenty, mozhet na neskol'ko poryadkov prevoshodit' sobstvennuyu svetimost' zvezdy. V rezul'tate voznikaet samopodderzhivayushayasya akkreciya, kotoraya idet v sushestvenno bolee vysokom tempe, chem mogla by obespechit' termoyadernaya evolyuciya zvezdy. Pri etom vozmozhen kak stacionarnyi, tak i ciklicheskii rezhim, pri kotorom veshestvo vypadaet na kompaktnyi ob'ekt porciyami i vyzyvaet vspyshki zhestkogo izlucheniya. Imenno poslednyaya, naibolee bogataya effektami situaciya, podrobno rassmatrivaetsya v dannom obzore.


    Vypusk 70. 16-22 fevralya 2004

    astro-ph/0402334 Modeli zvezd galo s ekstremal'no nizkoi metallichnost'yu (Models for extremely metal-poor halo stars)
    Authors: A. Weiss et al.
    Comments: submitted to Astron. Astrophys., 9 pages, 3 figures

    V galo nashei Galaktiki nablyudayutsya zvezdy s ochen' malym soderzhaniem elementov tyazhelee geliya. V etih ob'ektah nablyudaetsya nekotoroe kolichestvo ugleroda i azota, chto neobhodimo kak-to ob'yasnyat'. Sushestvuyut dve modeli. V pervoi iz nih zvezdy formiruyutsya "chistymi", a uglerod i azot narabatyvabtsya vo vremya gelievyh vspyshek v yadre. Vo vtoroi, nekotoroe kolichestvo tyazhelyh elementov iznachal'no vhodit v sostav zvezdy iz-za togo, chto protozvezdnoe veshestvo bylo obogasheno vzryvom blizkoi sverhnovoi.

    Avtory detal'no modeliruyut evolyuciyu zvezdy HE0107-5240 i prihodyat k vyvodu, chto vtoraya model' luchshe opisyvaet nablyudeniya.


    astro-ph/0402354 Astroseismologiya zvezdy nyu Eridana, peremennoi tipa beta Cefeya: interpretaciya i prilozhenie k spektru oscillyacii (Asteroseismology of the Beta Cephei star Nu Eridani: Interpretation and applications of the oscillation spectrum)
    Authors: A. A. Pamyatnykh et al.
    Comments: 8 pages, 7 figures, accepted in MNRAS

    Posle togo, kak osnovnye teoreticheskie problemy gelioseismologii byli uspeshno resheny, metody nablyudenii razrabotany i oprobovany, i finansirovanie dannogo napravleniya issledovanii sokratilos', chast' issledovatelei obnaruzhili, chto vse eti metody mozhno primenyat' i k naibolee yarkim zvezdam. Tak voznikla astroseismologiya.

    U zvezdy ν Eri, yavlyayusheisya peremennoi tipa β Cephei, nablyudaetsya samyi bogatyi spektr kolebanii.

    Spektr interpretiruetsya v terminah normal'nyh mod kolebanii zvezdy. Dannye o tom, kakie iz vozmozhnyh mod kolebanii vozbuzhdeny, a kakie net, pozvolyayut postroit' "seismicheskuyu" model' etoi zvezdy. Nablyudayusheesya rassheplenie dipol'nyh mod pozvolyaet sdelat' zaklyuchenie o skorosti vrasheniya yadra zvezdy.


    Vypusk 69. 08-15 fevralya 2004

    obzor astro-ph/0402186 Spektral'naya klassifikaciya i effektivnye temperatury L i T-karlikov na osnove spektrov v blizkom IK (Spectral Classification and Effective Temperatures of L and T Dwarfs Based of Near-Infrared Spectra)
    Authors: T.Nakajima, T.Tsuji and K.Yanagisawa
    Comments: 31 pages, 6 figures.

    Dlya samyh malen'kih zvezd, kotorye odnovremenno yavlyayutsya samymi tusklymi i holodnymi, i tem bolee dlya korichnevyh karlikov, v kotorye termoyadernye reakcii voobshe ne idut, ne hvataet obychnoi spektral'noi klassifikacii, zakanchivayusheisya zvezdami klassa M. V nee snachala byl dobavlen novyi spektral'nyi klass L, a zatem klass T. Spektral'naya klassifikaciya v etoi oblasti osnovana na analize nablyudenii v blizhnem infrakrasnom diapazone.

    V dannom obzore po dannym infrakrasnogo sputnika Subaru opredelyayutsya kriterii klassifikacii zvezd na podklassy: ot L0 do L9 i ot T0 do T8.


    astro-ph/0402207 Effektivnaya temperatura goryachih zvezd: Rannie O-zvezdy (The Effective Temperatures of Hot Stars II. The Early-O Types)
    Authors: Miriam Garcia and Luciana Bianchi
    Comments: 38 pages, 9 figures, 4 tables, accepted for ApJ

    Po opredeleniyu, effektivnaya temperatura, eto temperatura takogo absolyutno chernogo tela, kotoroe pri teh zhe razmerah i forme daet izluchenie takoi zhe moshnosti, chto i dannoe real'noe telo.

    U samyh goryachih zvezd, otnosyashihsya k spektral'nym klassam O3-O4, maksimum izlucheniya lezhit uzhe za predelami opticheskogo diapazona. Dlya opredeleniya effektivnoi temperatury takih zvezd prihoditsya privlekat' ih spektral'nye nablyudeniya v ul'trafioletovom i dalekom ul'trafioletovom diapazonah. Issledovaniya pokazali, chto effektivnye temperatury zvezd spektral'nyh klassov O3-O4 lezhat v intervale 39 000-41 000 K dlya karlikov i okolo 37 500 K dlya sverhgigatnov. Eti velichiny primerno na 20% men'she ispol'zovavshihsya ranee.


    Vypusk 68. 01-07 fevralya 2004

    astro-ph/0402015 UYSO 1 - ochen' molodoi massivnyi zvezdnyi ob'ekt (UYSO 1 - An Extremely Young Massive Stellar Object)
    Authors: J. Forbrich et al.
    Comments: 4 pages, 1 figure. (Co)authored by members of the MPIfR (Sub)millimeter Astronomy Group. To appear in the Proceedings of the 4th Cologne-Bonn-Zermatt-Symposium "The Dense Interstellar Medium in Galaxies" eds. S. Pfalzner, C. Kramer, C. Straubmeier, & A. Heithausen (Springer: Berlin)

    Nablyudat' rozhdenie zvezd ne ochen' prosto, t.k. na etoi stadii zvezdy pogruzheny v gazopylevye obolochki. Dostatochno effektivny nablyudeniya v millimetrovom diapazone. Imenno v hode takih issledovanii avtory obnaruzhili istochnik, kotoryi oboznachili UYSO 1: Unidentified Young Stellar Object 1. Po vsei vidimosti eto molodaya massivnaya (neskol'ko desyatkov mass solnca vmeste v obolochkoi) protozvezda. S nei svyazan moshnyi molekulyarnyi vybros (sm. risunok).


    astro-ph/0402094 Desyatka luchshih analogov Solnca iz biblioteki ELODIE (The Top Ten solar analogs in the ELODIE library)
    Authors: C. Soubiran, A. Triaud
    Comments: 12 pages, accepted in A&A

    ELODIE - eto biblioteka podrobnyh zvezdnyh spektrov. Proanalizirovav ee dannye, avtory vydelyayut desyatku zvezd, naibolee pohozhih na Solnce. Pervoe mesto ostalos' za HD 146233 - eto samyi blizkii analog Solnca. Dobavilis' i novye, do etogo neissledovannye zvezdy. Sushestvenno, chto v vyborku popali dve zvezdy s planetami: HD095128 i HD186427.


    Vypusk 67. 26-31 yanvarya 2004

    astro-ph/0401499 Evolyuciya Mlechnogo puti s samyh rannih etapov: ogranicheniya na zvezdnyi nukleosintez (The evolution of the Milky Way from its earliest phases : constraints on stellar nucleosynthesis)
    Authors: Patrick Francois et al.
    Comments: 20 pages, 10 figures, submitted to A&A

    Mozhno rassmatrivat' dinamicheskuyu evolyuciyu nashei galaktiki, mozhno rassmatrivat' spektral'nuyu evolyuciyu, a mozhno i himicheskuyu (sm. obzor v stat'e astro-ph/0401538). So vremenem himicheskii sostav galaktiki postoyanno menyaetsya v storonu uvelicheniya doli tyazhelyh elementov za schet sinteza v zvezdah. Za schet zvezdnyh vetrov i vzryvov veshestvo popadaet v mezhzvezdnuyu sredu, zatem v zvezdy novogo pokoleniya i t.d.

    V etoi rabote avtory modeliruyut himicheskuyu evolyuciyu Mlechnogo Puti, ispol'zuya novye dannye po evolyucii massivnyh zvezd i po sverhnovym tipa Ia. Zatem rezul'taty modeli sravnivayutsya s dannymi nablyudenii. Dlya sravneniya ispol'zovany samye novye dannye (osobenno po Solnechnoi okrestnosti). Na osnovanii sravneniya avtory delayut vyvody kak o parametrah modelei evolyucii zvezd i proizvodstva v nih elementov, tak i ob istorii nashei Galaktiki. Naprimer, is treh rassmotrennyh modelei sverhnovyh tol'ko odna bez modifikacii daet priemlemye rezul'taty.


    astro-ph/0401571 VLA 3.6cm obzor galakticheskih zvezd Vol'fa-Raie (A Very Large Array 3.6cm continuum survey of Galactic Wolf-Rayet stars)
    Authors: C. Cappa et al.
    Comments: Comments: 21 pages, Latex, 21 postscript figures, to be published in The Astronomical Journal, May 2004

    Na proshloi nedele my pisali o teorii neteplovogo radioizlucheniya massivnyh zvezd. A vot dannye nablyudenii. Na VLA na dline volny 3.6 sm avtory otnablyudali 34 galakticheskih zvezdy Vol'fa-Raie. Ot 15 iz nih bylo zaregistrirovano neteplovoe radioizluchenie (dlya 13 iz nih - vpervye), eshe 5 istochnikov yavlyayutsya vozmozhnymi kandidatami.


    astro-ph/0401638 Nablyudeniya pokrytii zvezd Lunoi v infrakrasnom i opticheskom diapazonah na polutorometrovom teleskope v Calar Alto dlya izmereniya diametrov zvezd i obnaruzheniya novyh dvoinyh sistem (Infrared and visual lunar occultations measurements of stellar diameter and new binary stars detections at the Calar Alto 1.5m telescope)
    Authors: O. Fors et al.
    Comments: 15 pages, 3 figures, LaTeX, uses aa.cls. Accepted for publication in A&A

    Po nablyudeniyam pokrytiya zvezd Lunoi mozhno opredelyat' ih diametry! Ob etom byli populyarnye stat'i na russkom (sm. naprimer, rabotu E. Trunkovskogo).

    V dannoi stat'e predstavleny rezul'taty primerno 40 nablyudenii. Dlya dvuh gigantov (30 Psc i V349 Gem) udalos' dostatochno tochno izmerit' diametry. Takzhe byli obnaruzheny ochen' tesnye dvoinye (SAO 164567, SAO 78258 i AG+24 788) s rasstoyanie mezhdu komponentami vsego lish' 0.006 uglovyh sekundy.


    Vypusk 66. 19-26 yanvarya 2004

    astro-ph/0401350 Razgadyvaya proishozhdenie buryh karlikov (Unraveling Brown Dwarf Origins)
    Authors: Ray Jayawardhana
    Comments: 3 pages, no figures, Science, 303, 322 (2004 January 16 issue)

    Malen'kaya populyarnaya stat'ya dlya zhurnala Science. Burye (korichnevye) karliki zanimayut razmytuyu polosu mezhdu malomassivnymi zvezdami i planetami. Pohozhe, chto eti ob'ekty tipichny kak v okrestnostyah Solnca, tak i v oblastyah zvezdoobrazovaniya. Ih proishozhdenie vse eshe obsuzhdaetsya. Nekotorye astronomy predpolagayut, chto burye karliki eto "zvezdnye embriony", vybroshennye iz novorozhdennyh kratnyh zvezdnyh sistem. Drugaya gipoteza: oni formiruyutsya kak obychnye zvezdy, v rezul'tate fragmentacii kollapsiruyushih gazovyh oblakov.


    astro-ph/0401360 O nedavnei istorii zvezdoobrazovaniya v diske Mlechnogo Puti (On the recent star formation history of the Milky Way disk)
    Authors: R. de la Fuente Marcos, C. de la Fuente Marcos
    Comments: 38 pages, 11 figures.

    Ob'emnaya i podrobnaya rabota: avtory pytayutsya vosstanovit' detal'nyi (s shagom 50 mln. let) vid funkcii zvezdoobrazovaniya v diske nashei Galaktiki za poslednie 2 mlrd. let po raspredeleniyu vozrastov rasseyannyh skoplenii. Strogo odnoznachnogo rezul'tata ne poluchilos', no, chto ochen' interesno, vidna nekotoraya ciklichnost' s periodom okolo 400 mln. let.

    Rekonstrukcii istorii Galaktiki na bOl'shih vremenah po sharovym skopleniyam posvyashena stat'ya astro-ph/0401366.


    astro-ph/0401376 Nukleosintez, reionizaciya i funkciya mass pervyh zvezd (Nucleosynthesis, Reionization, and the Mass Function of the First Stars)
    Authors: Jason Tumlinson et al.
    Comments: submitted to ApJ

    Vo mnogih populyarnyh na segodnyashnii den' modelyah pervoe pokolenie zvezd predstavleno ochen' massivnymi ob'ektami (140 mass solnca i bol'she). Avtory dannoi stat'i pytayutsya prodemonstrirovat', chto mozhno oboitis' bez vvedeniya stol' massivnyh zvezd. A imenno. Oni pokazyvayut, chto dannye po soderzhaniyu elementov v zvezdah galo nashei Galaktiki mozhno ob'yasnyat' rezul'tatom zhiznideyatel'nosti zvezd normal'nyh mass. A takzhe, chto dannye, poluchennye WMAP, po reionizacii (ili, kak eshe govoryat, vtorichnoi ionizacii) Vselennoi opisyvayutsya bez privlecheniya ochen' massivnyh zvezd.

    Avtory predlagayut ogranichit'sya funkciei mass, prostirayusheisya ot 10-20 mass Solnca do primerno 120 solnechnyh mass.


    astro-ph/0401385 Poisk peremennyh zvezd v central'noi chasti sharovogo skopleniya M22 (Searching for Variable Stars in the Central Part of the Globular Cluster M22)
    Authors: P.Pietrukowicz, J. Kaluzny
    Comments: 10 pages, 4 figures, Acta Astronomica v.53, p.371 (2004)

    Avtory sdelali popytku naiti peremennye zvezdy v centre sharovogo skopleniya M22 po serii fotografii s Habblovskogo teleskopa. Popytka okazalas' uspeshnoi: byli naideny 11 peremennyh zvezd iz kotoryh 8 - novye. Pyat' zvezd opredelenno yavlyayutsya zatmennymi dvoinymi, a odna otnositsya k tipu SX Phe. Nizhe pokazany oblast' poiska i krivye bleska naidennyh peremennyh zvezd.




    astro-ph/0401389 Neteplovoe radioizluchenie ot odinochnyh goryachih zvezd (Non-thermal radio emission from single hot stars)
    Authors: S. Van Loo, M.C. Runacres, R. Blomme
    Comments: 9 pages, 4 figures.

    Avtory razrabotali teoreticheskuyu model' neteplovogo izlucheniya ot odinochnoi goryachei zvezdy. Ono porozhdaetsya pri vzaimodeistvii ee moshnogo vetra s mezhzvezdnym veshestvom. Model' opisyvaetsya vsego pyat'yu parametrami.

    Dalee model' byla primenena k vysokokachestvennym nablyudeniyam zvezdy Cyg OB2 No. 9 (spektral'nogo klassa O5 If). Takoe sravnenie pozvolilo opredelit' nekotorye iz parametrov modeli:

    • udarnaya volna udalena ot zvezdy na rasstoyanie ot 500 do 2200 ee radiusov;
    • sama volna dostatochno slabaya (veshestvo v nei szhimaetsya menee, chem v 3 raza).

    Nu i, konechno, poluchennye rezul'taty obsuzhdayutsya.


    Vypusk 65. 12-19 yanvarya 2004

    astro-ph/0401141 Necentral'noe zazhiganie ugleroda v bystrovrashayushihsya akkreciruyushih Uglerodno-kislorodnyh belyh karlikah (Off-Center Carbon Ignition in Rapidly Rotating, Accreting Carbon-Oxygen White Dwarfs)
    Authors: Hideyuki Saio and Ken'ichi Nomoto
    Comments: 7 pages, 4 figures

    Termoyadernoe gorenie belogo karlika vyzyvaet vzryv sverhnovoi tipa Ia. Nachinaetsya etot process v samyh plotnyh sloyah zvezdy: v ee centre. Eto utverzhdenie sovershenno verno dlya nevrashayushihsya, sfericheski simmetrichnyh karlikov. Ono ostaetsya vernym pri medlennom i umerenno bystrom ih vrashenii. No kogda skorost' vrasheniya na ekvatore stanovitsya sravnimoi s Keplerovoi, situaciya menyaetsya: gorenie mozhet nachat'sya ne v centre zvezdy, a na nekotorom rasstoyanii ot nego.

    Krome togo bystro vrashayushiesya belye karliki dol'she ne zagorayutsya. Iz etogo avtory raboty delayut vyvod, chto sliyaniya dvoinyh belyh karlikov ne dolzhny privodit' k sverhnovym Ia (t.e. takie sverhnovye porozhdayutsya iz medlenno vrashayushihsya belyh karlikov v tesnyh sistemah s normal'nymi kompan'onami).

    Smotrite, takzhe, stat'yu na svyazannuyu temu "Explosion models for thermonuclear supernovae resulting from different ignition conditions" (astro-ph/0401230).


    astro-ph/0401192 Otkrytie kompan'ona dvoinoi sistemy v vide ochen' holodnogo belogo karlika (Discovery of an Ultracool White Dwarf Companion)
    Authors: J. Farihi
    Comments: 26 pages, 9 figures, 3 tables, accepted to ApJ

    U belogo karlika GD392 (teper' GD392A) otkryt vtoroi kompan'on - ochen' holodnyi belyi karlik s nizkoi svetimost'yu. Vtoroi kompan'on, nazvannyi GD392B, nahoditsya ot pervogo na rasstoyanii 46", ih svyaz' byla ustanovlena po odinakovym sobstvennym dvizheniyam. Novyi belyi karlik deistvitel'no ochen' holodnyi: rezul'taty BVRIJHK fotometrii pokazali nalichie v ego spektre absorbcionnoi detali, vyzyvaemoi molekulyarnym(!) vodorodom H2. Segodnya izvestno uzhe neskol'ko podobnyh belyh karlikov, no GD392B pervyi, vhodyashii v dvoinuyu sistemu.


    katalog astro-ph/0401217 Obzor peremennyh zvezd severnogo neba: otkrytaya versiya (Northern Sky Variability Survey (NSVS): Public data release)
    Authors: P.R.Wozniak et al.
    Comments: accepted for AJ

    Obzor peremennyh zvezd severnogo neba (The Northern Sky Variability Survey =NSVS) postroen po rezul'tatam avtomaticheskogo teleskopa ROTSE-I - pervogo "lovca" gamma-vspleskov. Katalog soderzhit peremennye nablyudeniya zvezd severnogo neba (i chasti yuzhnogo vblizi ekvatora) ot 8 do 15.5 zvezdnoi velichiny. Vsego v kataloge primerno 14 000 000 ob'ektov, na kazhdyi iz kotoryh prihoditsya ot 100 do 500 nablyudenii (v katalog voshli nablyudeniya za 1 god). Katalog dostupen v Internet na portale Sky Database for Objects in Time-Domain (SkyDOT, http://skydot.lanl.gov) Los-Alamosskoi Nacional'noi Laboratorii.


    Vypusk 64. 01-11 yanvarya 2004

    astro-ph/0401004 Stolknoveniya zvezd v rezul'tate vzaimodeistviya dvoinyh i odinochnyh ob'ektov (Stellar Collisions During Binary-Binary and Binary-Single Star Interactions)
    Authors: J. M. Fregeau, P. Cheung, S. F. Portegies Zwart, F. A. Rasio
    Comments: Submitted to MNRAS; 28 pages, 22 figures, 7 tables

    Sredi zvezd vstrechayutsya dostatochno lyubopytnye ekzemplyary, kotorye ne ob'yasnyayutsya standartnymi scenariyami obrazovaniya i evolyucii zvezd. Naprimer, temperatura ili radius zvezdy mogut nesootvetstvovat' ee masse. Odno iz vozmozhnyh ob'yasnenii svyazano s tem, chto ob'ekt ispytal "vstryasku", naprimer iz-za sil'nogo vzaimodeistviya s drugoi zvezdoi.

    Avtory modeliruyut evolyuciyu zvezd v plotnyh skopleniyah, gde istochniki raspredeleny nastol'ko tesno, chto proishodyat stolknoveniya. Prichem, esli vo vzaimodeistvie vovlechena dvoinaya sistema, to velika veroyatnost' sliyaniya neskol'kih zvezd. Pri etom obrazuyutsya ob'ekty radiusami v 2-30 raz bol'she, chem u normal'noi zvezdy glavnoi posledovatel'nosti (dlya toi zhe massy).


    astro-ph/0401056 Kol'ca v galo planetarnyh tumannostei (Rings in the Haloes of Planetary Nebulae)
    Authors: R.L.M. Corradi et al
    Comments: 10 pp., 4 figs, accepted by A&A main journal

    Avtory dannoi raboty predprinyali poisk kol'cevyh (i dugoobraznyh) struktur v planetarnyh tumannostyah. I nashli ih! U vos'mi ob'ektov. Teper' takih tumannostei stalo vtroe bol'she. Nalichie takih struktur ukazyvaet, chto peremennost' zvezdnogo vetra v planetarnyh tumannostyah na vremennyh shkalah ot 100 do 1000 let, gorazdo bolee chastoe yavlenie dlya zvezd vblizi konca asimptoticheskoi vetvi gigantov (na diagramma Gercshprunga-Rassela), chem polagalos' ranee. Chislo takih sistem dolzhno sostavlyat' primerno 35%.


    Negativnye izobrazheniya chetyreh iz vos'mi tumannostei, u kotoryh naideny kol'cevye struktury. Sleva - ishodnye negativy, v centre i sprava izobrazheniya, povergnutye special'noi obrabotke, na kotoryh horosho vidny kol'ca.


    (Arhiv Zvezdy:
    v.2, 2003, v.1, 2002-2003)

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