The R.A.P. Project (Reviews of Astro-Ph)
Zvezdy
(Arhiv Zvezdy: v.2, 2003,
v.1, 2002-2003)
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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ru_astroph.
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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.
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.
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.
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.
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.
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.
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.
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
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Obsudit' na Astroforume v
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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.
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.
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.
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.
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.
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.
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).
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
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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.
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.
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.
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.
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
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.
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.
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!
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.
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.
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.
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.
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).
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.
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.
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.
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.
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.
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'.
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.
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'.
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.
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.
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.
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.
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.
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.
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.
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.
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).
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.
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).
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.
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.
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.
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.
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.
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).
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!
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.
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'.
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.
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.
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'!
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.
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.
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.
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'.
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.
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.
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.
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.
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'.
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.
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'.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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
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.
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
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.
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'.
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'.
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.
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.
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.
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.
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.
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
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.
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.
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).
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.
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.
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.
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.
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.
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.
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).
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.!
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.
Authors: Christopher F. McKee, Eve C. Ostriker
Comments: 120 pages, to appear in ARAA.
Obsuzhdayutsya vse aspekty obrazovaniya zvezd.
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.
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.).
Authors: Hans Zinnecker, Harold W. Yorke
Comments: 139 pages, 18 figures, 5 tables, glossary
Gigantskii obzor po obrazovaniyu massivnyh zvezd. Vklyucheno ochen' mnogo materiala.
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.
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.
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'.
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.
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.
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.
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.
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.
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.
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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.
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.
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.
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.
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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.
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!
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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.
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.
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.
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.
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!
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!
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.
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.
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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.
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'.
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.
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'.
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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.
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.
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.
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).
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.
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'.
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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'.
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.
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.
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.
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.
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'.
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.
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.
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.
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.
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.
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.
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.
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.
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!
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.
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.
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.
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.
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.
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.
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.
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!
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.
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'.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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).
Authors: G. J. Mathews et al.
Comments: 11 pages, 6 figures, accepted for publication in J. Phys. G: Nucl. Part. Phys
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.
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 :)
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.
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.
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.
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).
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.
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.
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.
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.
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...
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).
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.
Authors: G. Chabrier et al.
Comments: Invited Review, Protostars and Planets V (Hawai, October 2005)
Podrobnyi obzor, posvyashennyi tematikam, privedennym v nazvanii. Rekomenduyu.
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.
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.
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.
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.
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!
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).
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.
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!
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).
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.
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.
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'.
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.
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.
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.
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.
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.
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.
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".
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.
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.
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).
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.
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.
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.
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.
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.
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.
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.
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.
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.