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Soderzhanie i bystryi perehod k razdelam obzora
Global'noe zondirovanie kosmologicheskih magnitnyh polei na bol'shih krasnyh smesheniyah Nazemnye obzory po poisku peremennyh istochnikov v Centavre A: stoit ili net? Taina holodnogo pyatna WMAP Gigantskaya vspyshka istochnika myagkih povtoryayushihsya gamma-vspleskov v Tumannosti Andromedy, M31 Registraciya mezhgalakticheskogo meteora na 6-metrovom teleskope
Otdel'nye stat'i
Iz razdela physics
Polnyi Arhiv predydushih vypuskov. Arhiv statei, voshedshih v vypuski s 01 iyulya 2002 g. po 31 marta 2003 g.
Arhiv na 14.04.2006
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Razdely arhiva (s aprelya 2003 g.): Poleznye astronomicheskie ssylki. Korotkoe esse ob elektronnyh preprintah. Obzornye stat'i v astro-ph 2001-2003 gg.
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Referaty otdel'nyh statei
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.
arxiv:0712.0247
Scenarii samoobogasheniya sharovyh skoplenii promezhutochnoi metallichnosti
(The self-enrichment scenario in intermediate metallicity globular clusters).
Authors: P. Ventura & F. D'Antona Comments: A&A, 26 pages Stat'ya yavlyaetsya prodolzheniem serii rabot teh zhe avtorov ob evolyucii zvezd promezhutochnyh mass na stadii asimptoticheskoi vetvi gigantov (AGB stars). Predstavleny rezul'taty chislennogo modelirovaniya evolyucii zvezd v intervale mass 3 < M < 6.3 solnechnyh mass, s pervonachal'nym obiliem geliya Y=0.24 i metallichnost'yu Z=0.001, sootvetstvuyushei [Fe/H]= -1.3 Poluchennye v rezul'tate raschetov teoreticheskie zvezdnye vybrosy (stellar yields) dlya izotopov 12C, 14N, 16O, 19F, 23Na, 25Mg, 26Mg, 27Al sravnivalis' s nablyudaemymi obiliyami v zvezdah sharovyh skoplenii toi zhe metallichnosti. Cel'yu raboty stala proverka gipotezy o vozmozhnosti samoobogasheniya sharovyh skoplenii AGB-zvezdami. Soglasno etoi gipoteze, nablyudaemye v sharovyh skopleniyah himicheskie anomalii i antikorrelyacii obilii O-Na i Mg-Al mozhno ob'yasnit' bystroi evolyuciei pervogo pokoleniya massivnyh AGB-zvezd, obogashayushih mezhzvezdnuyu sredu protoskoplenii tyazhelymi elementami i stimuliruyushih formirovanie vtorogo pokoleniya zvezd, nablyudaemyi himsostav kotoryh otrazhaet sostav obogashennogo gaza. Predskazaniya modeli nahodyatsya v horoshem soglasii s nablyudaemymi obiliyami kisloroda, alyuminiya, ftora i magniya, no ne sposobny ob'yasnit' soderzhaniya natriya i litiya. Po ocenke avtorov, tol'ko samye massivnye AGB-zvezdy s massami 5-6 solnechnyh mass vliyayut na process samoobogasheniya protoskoplenii.
Authors: Alessandro De Angelis, Oriana Mansutti, Massimo Persic Comments: 20 pages, Invited Review Talk at the Sixth International Workshop on New Worlds in Astroparticle Physics, September 6-8, 2007, University of the Algarve, Faro, Portugal Bol'shoi dostatochno populyarnyi obzor po gamma-astronomii. Vse osnovnye ustanovki (i nazemnye, i sputnikovye), rezul'taty i modeli upomyanuty. Razumeetsya, ne zabyty i proekty blizhaishego budushego.
Authors: P. P. Kronberg, et al. Comments: 10 pages, 8 figures Astrophysical Jounrnal in press, March 2008 Issledovanie mer vrasheniya bol'shogo chisla dalekih radioistochnikov pokazalo, chto za z~2 dolya ob'ektov s maloi meroi vrasheniya ochen' mala. T.e., kak pisht avtory "vselennaya faradeevski neprozrachna". Po ih mneniyu, eto govorit o tom, chto v rannie epohi okrestnosti galaktik byli dostatochno sil'no zamagnicheny. Drugaya vozmozhnost' sostoit v tom, chto velik vklad sobstvennyh polei istochnikov.
arxiv:0712.0538
Obnaruzhimye sledstviya radiacionnoi obratnoi svyazi pri reionizacii
(Detectable Signatures of Cosmic Radiative Feedback).
Authors: R. Schneider et al. Comments: MNRAS, 9 pages Avtorami razrabotana poluanaliticheskaya model', pozvolyayushaya uchest' vliyanie reoinizacii na process formirovaniya galaktik. Rassmotreny dva varianta modeli s razlichnymi scenariyami radiacionnoi obratnoi svyazi. Oba varianta nahodyatsya v soglasii s ogranicheniyami SDSS na soderzhanie neitral'nogo vodoroda na z < 7. Predskazannye razlichiya dlya tomsonovskoi opticheskoi tolshi nahodyatsya v predelah odnoi sigma po rezul'tatam trehletnih nablyudenii WMAP. Oba varianta soglasuyutsya s dannymi ob evolyucii Laiman-limit sistem (LLS), kosmicheskoi istorii zvezdoobrazovaniya, teplovoi istoriei mezhgalakticheskoi sredy, podschetom galaktik na bol'shih krasnyh smesheniyah. Po mneniyu avtorov, lish' nablyudeniya v linii HI 21 sm pozvolyat sdelat' vybor, kakoi iz variantov yavlyaetsya nabolee realistichnym. V stat'e obsuzhdaetsya veroyatnost' obnaruzheniya signala s pomosh'yu sushestvuyushih i razrabatyvaemyh radioteleskopov.
arxiv:0712.0582
Svidetel'stvo izbytochnogo zvezdoobrazovaniya v yarkih i ochen' yarkih
infrakrasnyh galaktikah (Evidence of enhanced star formation efficiency in
luminous and ultraluminous infrared galaxies).
Authors: J. Graci'a-Carpio et al. Comments: A&A, 15 pages V rabote predstavleny rezul'taty nablyudenii na 30-metrovom radioteleskope IRAM, provedennyh s cel'yu izucheniya plotnogo molekulyarnogo gaza v 17 blizkih yarkih i ochen' yarkih infrakrasnyh galaktikah (LIRGs i ULIRGs). Avtory privodyat nablyudatel'nye dokazatel'stva togo, chto effektivnost' zvezdoobrazovaniya v plotnom molekulyarnom gaze yarkih infrakrasnyh galaktik namnogo effektivnee, chem v normal'nyh galaktikah - rezul'tat, nedavno podtverzhdennyi dlya galaktik na bol'shih krasnyh smesheniyah. Obsuzhdaetsya vozmozhnost' ispol'zovaniya izlucheniya molekuly HCN kak indikatora plotnogo molekulyarnogo gaza v infrakrasnyh galaktikah.
Obzor
arxiv:0712.0828
Formirovanie massivnyh zvezd (The Formation of Massive Stars).
Authors: M.R. Krumholz & I.A.Bonnell Comments: To be published in Structure Formation in the Universe, 26 pages Processy rozhdeniya i evolyucii massivnyh zvezd malo izucheny, nesmotrya na sushestvennyi teoreticheskii i nablyudatel'nyi progress v etoi oblasti v poslednie gody. Obzor posvyashen detal'nomu rassmotreniyu dvuh naibolee populyarnyh modelei formirovaniya massivnyh zvezd: modeli vnutrennei akkrecii (core accretion) i poperemennoi akkrecii (competitive accretion). Eti podhody otlichayutsya tem, kogda i kakim obrazom nabiraetsya okonchatel'naya massa budushei zvezdy. Obzor sostoit iz pyati chastei: vvedeniya, opisaniya kazhdoi iz modelei, nereshennyh zadach i budushih nablyudenii.
Authors: F. Mignard et al. Comments: 7 pages, 2 figures, Proceedings of IAU Symp. 248 Astrometricheskii sputnik GAIA budet peredavat' ochen' bol'shoi potok dannyh. Rech' idet primerno o 100 Terabaitah za pyat' let raboty. V stat'e opisyvayutsya osnovnye slozhnosti pri rabote s etimi dannymi i puti resheniya problem.
Authors: W. Schmidt Comments: 18 pages, 7 figures; proceedings contribution to "Structure formation in the Universe: Chamonix 2007" Nebol'shoi obzor, posvyashennyi dostatochno populyarnomu izlozheniyu togo, kak modeliruyut turbulentnost' voobshe, a v osobennosti v sluchae mezhzvezdnoi sredy.
arxiv:0712.0965
Ocenka polnoi infrakrasnoi svetimosti galaktik vplot' do z~2 na osnove
dannyh infrakrasnyh nablyudenii v srednem i dalekom diapazonah
(Estimating the total infrared luminosity of galaxies up to z ~ 2
from mid- and far-infrared observations).
Authors: N. Bavouzet et al. Comments: A&A, 16 pages Predstavlennaya v rabote vyborka soderzhit 372 infrakrasnye galaktiki na krasnyh smesheniyah z < 0.8. Nablyudeniya galaktik provodilis' na dlinah voln 8, 24, 70 and 160 mkm s pomosh'yu kosmicheskogo teleskopa Spitzer. Bylo naideno, chto infrakrasnye monohromaticheskie svetimosti galaktik na ukazannyh dlinah voln strogo korreliruyut s polnoi infrakrasnoi svetimost'yu L_ir galaktik. Polucheny empiricheskie formuly dlya ocenki L_ir na osnove infrakrasnyh potokov v fil'trah. Krome togo, avtory ne obnaruzhili svidetel'stv znachitel'noi evolyucii spektral'nyh energeticheskih raspredelenii izuchennyh galaktik v infrakrasnoi oblasti v zavisimosti ot krasnogo smesheniya i potomu isklyuchayut veroyatnost' sushestvennoi evolyucii svoistv pylevyh chastic vplot' do krasnyh smeshenii z~1. V rabote takzhe obsuzhdaetsya komplementarnost' infrakrasnyh i submillimetrovyh nablyudenii galaktik.
Authors: J. P. Dietrich Comments: 5 pages, accepted for publication in PASP Poleznye melochi: chem blizhe vasha stat'ya k nachalu ezhednevnogo vypuska arhiva preprintov, tem vyshe u nee shansy stat' horosho citiruemoi! Moei pervoi mysl'yu bylo, chto delo prosto v tom, chto vazhna geografiya: yasno, chto iz-za raznicy vo vremeni vyshe v spiske postoyanno okazyvayutsya stat'i iz odnih i teh zhe stran. No avtory isklyuchayut etu vozmozhnost'. Tak chto v samom dele, vazhno byt' blizhe k nachalu. Interesno, nachnut li lyudi massovo uchityvat' etot aspekt?
Authors: Rosalba Perna et al. Comments: 12 pages, 2 figures, accepted for publication in MNRAS My poka ploho znaem, kakimi rozhdayutsya neitronnye zvezdy: kakie u nih magnitnye polya, periody, massy, prostranstvennye skorosti. Ved' nablyudaem my uzhe proevolyucionirovavshie ob'ekty, da eshe vdobavok te, ktorye proshe uvidet' (naprimer, radio pul'sary). Vosstanovlenie nachal'nyh parametrov chashe vsego proishodit putem primeneniya populyacionnyh modelei. A hotelos' by bol'she pryamyh dannyh. Avtory predlagayut ispol'zovat' rntgenovskie nablyudeniya sverhnovyh. Esli tam rodilas' neitronnaya zvezda, to my mozhem dat' ogranichenie na dopolnitel'noe energovydelenie, svyazannoe s kompaktnym ob'ektom. Energovydelenie zavisit ot vrasheniya i magnitnogo polya, znachit, my mozhem ogranichit' nekotoruyu kombinaciyu etih parametrov. Razumeetsya, net neobhodimosti nablyudat' sverhnovuyu v moment vzryva. Bolee togo, togda tol'ko bystrovrashayushiesya magnitary mogut vnesti kakoi-to sushestvennyi vklad. Rech' idet ob issledovanii istoricheskih sverhnovyh (t.e., kogda vozrast tochno izvesten). Ispol'zovalis' nablyudeniya na sputnike Chandra. Po mneniyu avtorov, oni mogut isklyuchit' dominirovanie sredi neitronnyh zvezd teh, chto rodilis' s ochen' korotkimi periodami. Konechno, dlya etogo im prishlos' zadat'sya neotorymi model'nymi predpolozheniyami (magnito-dipol'naya formula dlya energovydeleniya, nekotoroe raspredelenie po magnitnym polyam, izvestnoe po dannym o radiopul'sarah). Tem ne menee podhod interesnyi. V zaklyuchenie otmechu, chto avtoram ne udalos' dat' ogranicheniya na nachal'nye periody magnitarov, poskol'ku te slishkom bystro zamedlyayutsya iz-za sverhsil'nyh magnitnyh polei. Tak chto k momentu nablyudenii vklad podobnyh obhektov v rentgenovskuyu svetimost' ostatka sverhnovoi byl by kraine mal.
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.
Obzor
arxiv:0712.1100
Pervichnyi nukleosintez v epohu precizionnoi kosmologii
(Primordial Nucleosynthesis in the Precision Cosmology Era).
Authors: Gary Steigman Comments: Annu. Rev. Nucl. Part. Sci. 2007, 29 pages V 1985 godu v zhurnale Annu. Rev. Astron. Astrophys. vyshel obzor "Big Bang Nucleosynthesis: Theories and Observations", napisannyi dvumya avtorami Boesgaard & Steigman. Proshlo bolee dvadcati let, i Gari Staigman vnov' summiruet naibolee vazhnye otkrytiya v oblasti pervichnogo nukleosinteza. Obzor napisan na dostupnom dlya nekosmologov urovne i sostoit iz pyati chastei: vstupleniya, kratkoi annotacii modelei standartnogo i nestandartnogo nukleosinteza pri Bol'shom Vzryve, opisaniya nablyudatel'nyh dannyh po reliktovym nuklidam (deiterii, gelii-3, gelii-4, litii-7), obsuzhdeniya soglasiya mezhdu sovremennoi teoriei i nablyudeniyami, zaklyucheniya.
arxiv:0712.1108
Izbytok cveta u kvazarov s DLA-sistemami na luche zreniya. Analiz pyatogo reliza SDSS
(The color excess of quasars with intervening DLA systems. Analysis of the SDSS data release five).
Authors: Giovanni Vladilo et al. Comments: A&A, 17 pages Dannye pyatogo reliza obzora SDSS proanalizirovany avtorami s cel'yu vyyasnit' nablyudaetsya li izbytok cveta (pokrasnenie) u teh kvazarov, v spektre kotoryh prisutstvuyut absorbcionnye DLA-sistemy (protogalaktiki). Iz obshego spiska 5164 kvazarov byli otobrany 248 kvazarov s DLA-sistemami na luche zreniya i 1959 kontrol'nyh kvazarov, v spektrah kotoryh ne nablyudalos' absorbcionnyh sistem. V analize byli ispol'zovany tol'ko kachestvennye spektry s otnosheniem signal k shumu SNR > 4. Statisticheskie testy podtverdili nalichie pokrasneniya u kvazarov s DLA sistemami. Analiz pokazal, chto pokrasnenie kvazarov voznikaet iz-za pyli, prinadlezhashei imeeno DLA sistemam. Harakter krivoi ekstinkcii etih protogalaktik predpolozhitel'no takoi, kak u Malogo Magellanova Oblaka. Sootnoshenie pyl'-k-gazu v neskol'ko raz men'she analogichnogo dlya Galaktiki, chto soglasuetsya s obshei nizkoi metallichnost'yu DLA-sistem.
Obzor
arxiv:0712.1109
Formirovanie massivnyh zvezd: mogushestvo interferometrii
(Massive Star Formation: The Power of Interferometry).
Authors: H. Beuther Comments: Review on the occasion of the Ludwig Biermann prize of the German Astronomical Society, 35 pages Eshe odin obzor ob evolyucii massivnyh zvezd, osnovnoe vnimanie v kotorom udeleno fizicheskim i himicheskim svoistvam massivnyh zvezd. Obsuzhdaetsya ryad ogranichenii, poluchennyh na osnove submillimetrovoi interferometrii. Detal'no opisany osnovnye koncepcii fiziki i astrohimii massivnyh zvezd, predlozheny nablyudatel'nye testy dlya proverki sushestvuyushih gipotez.
Authors: Pavel D. Naselsky et al. Comments: 11 pages, 15 figures, submitted to ApJ Na kartah mikrovolnovogo fona (reliktovogo izlucheniya), postroennyh komandoi WMAP, est' zagadochnoe holodnoe pyatno na galakticheskoi shirote -57 i dolgote 209 gradusov. Avtory stat'i provodyat podrobnyi analiz. Hitrost' tut v tom, chto karty mikrovolnovogo fona stroyatsya sovsem ne tak, kak obychnye karty. T.e. eto ne nanesenie na kartu neba "tochek" s izmerennoi temperaturoi. Postroenie karty zavyazano zdes' na slozhnye metody obrabotki. V itoge mozhet poluchit'sya tak, chto nekotorye "detali" na karte voznikayut imenno v sledstvii primeneniya konkretnogo algoritma postroeniya, a vovse ne iz-za sushestvovaniya kakih-to vydelennyh oblastei na nebe. Pohozhe, chto imenno tak i poyavilos' holodnoe pyatno. Avtory detal'no razbirayut, kakie garmoniki mogli vnesti vklad v poyavlenie etogo "mirazha".
arxiv:0712.1160
Nukleosintez v rannei vselennoi i konechnye stadii evolyucii zvezd promezhutochnyh mass nulevoi metallichnosti
(An Explosive End to Intermediate-Mass Zero-Metallicity Stars and Early Universe Nucleosynthesis).
Authors: H.B. Lau et al. Comments: MNRAS, 18 pages Vopros o tom, formiruyutsya li zvezdy promezhutochnyh mass nulevoi (ili predel'no nizkoi) metallichnosti v usloviyah rannei vselennoi, i, esli da, to kakoi vklad oni vnosyat v nukleosintez, ochen' vazhen dlya ponimaniya himicheskoi evolyucii vselennoi. V dannoi rabote predstavleny rezul'taty modelirovaniya massivnyh (5 i 7 mass Solnca) AGB-zvezd nulevoi metallichnosti. Soglasno raschetam avtorov, osobennost' evolyucii massivnyh AGB-zvezd pervichnogo himsostava sostoit v tom, chto v ih central'nyh oblastyah zagoraetsya uglerod, i evolyuciya takih zvezd zakanchivaetsya vzryvom sverhnovyh tipa 1.5, napominayushim vzryv sverhnovyh tipa SN Ia, no s vodorodnoi obolochkoi. Eshe odnoi osobennost'yu evolyucii AGB-zvezd nulevoi metallichnosti yavlyaetsya otsutstvie etapa tret'ego peremeshivaniya (third dredge-up). Vazhnym sledstviem dlya himicheskoi evolyucii yavlyaetsya to, chto elementy s-processa pri etom ne obrazuyutsya, i obogasheniya mezhzvezdnoi sredy imi ne proishodit. Dlya utochneniya nizhnego poroga metallichnosti AGB-zvezd, pri kotorom "vklyuchaetsya" process tret'ego peremeshivaniya, trebuyutsya dal'neishie issledovaniya.
arxiv:0712.1185
SpectroWeb: sily oscillyatorov absorbcionnyh linii atomov v spektrah Solnca i Prociona
(SpectroWeb: oscillator strength measurements of atomic absorption lines in the Sun and Procyon).
Authors: A. Lobel Comments: To appear in Proc. of the 9th Int. Coll. on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas at Lund, 6 pages SpectroWeb - special'no razrabotannyi dlya astronomicheskogo soobshestva onlainovyi resurs, kotoryi soderzhit interaktivnyi cifrovoi spektral'nyi atlas yarkih zvezd i dostupen po adresu http://spectra.freeshell.org. Neobhodimost' v edinom standartnom atlase, obnovlyaemom, redaktiruemom i dostupnom vsem zhelayushim, voznikla v svyazi s bystrym progressom v oblasti zvezdnoi spektroskopii. V nastoyashii moment SpectroWeb soderzhit spektry vysokogo razresheniya shesti yarkih zvezd: Betelgeuse (alpha Ori; M2 Iab), Arcturus (alpha Boo; K1 III), The Sun (G2 V), beta Aqr (G0 Ib), Procyon (alpha CMi A; F5 IV-V) i Canopus (alpha Car; F0 II). Effektivnye temperatury etih zvezd otlichayutsya v srednem na 1000 K i sootvetstvuyut intervalu zvezdnyh temperatur ot 3500 K (M) do 7500 K (F). Dannaya publikaciya soderzhit informaciyu o vnesennyh v atlas SpectroWeb dopolneniyah. Dobavleny sily lineinyh oscillyatorov log(gf) dlya 1178 absorbcionnyh linii v spektre Solnca i sily lineinyh oscillyatorov log(gf) dlya 660 linii v spektre Prociona.
arxiv:0712.1202
Modelirovanie spektral'nyh energeticheskih raspredelenii ULIRGs. II: Energetika okruzheniya
i plotnaya mezhzvezdnaya sreda (Modelling the spectral energy distribution of ULIRGs.
II: The energetic environment and the dense interstellar medium).
Authors: O. Vega et al. Comments: A&A, 28 pages V rabote predstavleny sobrannye v literature spektry 30 galaktik ULIRGs (ultraluminous infrared galaxies), pokryvayushie diapazon ot blizkogo infrakrasnogo (1.23 mkm) do radiodiapazona (160 mkm). Kazhdyi iz 30 spektrov byl detal'no promodelirovan s pomosh'yu spektrofotometricheskogo koda GRASIL, razrabotannogo avtorami publikacii. Byli ispol'zovany kak modeli so vspyshkami zvezdoobrazovaniya, tak i modeli, uchityvayushie vklad AGN. Rezul'taty raschetov predstavleny v stat'e dlya kazhdoi iz 30 galaktik. Privedeny ocenki opticheskoi tolshi v napravlenii istochnika svetimosti, tempa zvezdoobrazovaniya i vliyaniya AGN.
arxiv:0712.1226
Fotometricheskie svoistva karlikovyh galaktik, prinadlezhashih Mestnomu Ob'emu
(Photometric properties of Local Volume dwarf galaxies).
Authors: M. E. Sharina et al. Comments: MNRAS, 29 pages V rabote predstavleny rezul'taty poverhnostnoi fotometrii i ocenki metallichnosti dlya 104 karlikovyh galaktik na osnove dannyh nablyudenii habblovskogo teleskopa i 26 karlikovyh galaktik iz dannyh obzora SDSS. Vyborka soderzhit karlikovye ellipticheskie, irregulyarnye i galaktiki perehodnyh tipov, nahodyashiesya v predelah 10 megaparsek, prinadlezhashie polyu i skopleniyam galaktik M81, Centavr A, Skul'ptor i Gonchie Psy. Poluchennye sootnosheniya mezhdu metallichnost'yu, strukturnymi i fotometricheskimi svoistvami karlikovyh galaktik nahodyatsya v horoshem soglasii s naidennymi ranee zakonomernostyami dlya karlikovyh galaktik Mestnoi gruppy. Bylo naideno, chto pri zadannoi svetimosti karlikovye galaktiki rannih tipov imeyut v srednem bol'shuyu metallichnost' po sravneniyu s galaktikami pozdnih tipov. Obsuzhdaemye v rabote korrelyacii mezhdu fundamental'nymi galakticheskimi parametrami soglasuyutsya so scenariem formirovaniya karlikovyh galaktik pod vliyaniem galakticheskogo vetra, vyzvannogo vzryvom sverhnovyh zvezd.
Authors: B.D. Metzger, E. Quataert, T.A. Thompson Comments: 5 pages, 2 figures; submitted to MNRAS Letters Dlya raznyh podvidov gamma-vspleskov prodozhayut predlagat' i razrabatyvat' raznye scenarii. Vse oni vklyuchayut v sebya obrazovanie kompaktnogo ob'ekta i diska vokrug nego, no detali razlichayutsya. Naprimer, est' korotkie vspleski, u kotoryh v dopolnenie k osnovnomu impul'su vidyat takzhe shirokii vsplesk dlitel'nost'yu do 100 sekund. V dannyh SWIFT takih nemalo. V etoi stat'e avtory razvivayut model', v kotoroi takie vspleski porozhdayutsya protomagnitarom, voznikshim ili pri kollapse belogo karlika, ili pri sliyanii belyh karlikov ili neitronnyh zvezd. Trebuyutsya dostatochno ekstremal'nye parametry: pole 3 1015 gauss pri periode 1 msek.
arxiv:0712.1239
Metallichnost' mezhgalakticheskoi sredy na osnove metoda tochechnoi statistiki: IV. Kislorod
(Metallicity of the intergalactic medium using pixel statistics: IV. Oxygen).
Authors: A. Aguirre et al. Comments: ApJ, 13 pages Izuchenie himicheskogo sostava mezhgalakticheskoi sredy na razlichnyh krasnyh smesheniyah pokazalo nalichie v nei tyazhelyh elementov uzhe na z = 5-6 i otsutstvie sushestvennoi evolyucii v metallichnosti dlya intervala krasnyh smeshenii 2 < z < 4. Process obogasheniya mezhgalakticheskoi sredy yavlyaetsya klyuchevym dlya ponimaniya evolyucii galaktik, potomu nablyudeniya mezhgalakticheskoi sredy byli i ostayutsya odnim iz prioritetnyh napravlenii. Dannaya stat'ya yavlyaetsya chetvertoi v serii rabot i posvyashena analizu linii O VI, C IV, Si IV i H I v spektrah vysokogo razresheniya 17 kvazarov, poluchennyh dlya na teleskopah VLT i Keck. Rezul'taty issledovaniya pokazali, chto na intervale krasnyh smeshenii 1.9 < z < 3.6 soderzhanie kisloroda [O/H] v mezhgalakticheskoi srede sushestvenno ne menyaetsya. Analogichnyi rezul'tat byl poluchen ranee temi zhe avtorami iz analiza obiliya v mezhgalakticheskoi srede ugleroda [C/H].
Authors: Deborah N. Aguilera, Jose A. Pons, Juan A. Miralles Comments: 4 pages, 3 figures, 1 table. Accepted for publication in APJ Letters Dazhe esli nauchit'sya pravil'no schitat' vse processy ohlazhdeniya v sverhplotnom sverhtekuchem veshestve v nedrah neitronnoi zvezdy, to eto eshe ne znachit, chto my mozhem sravnivat' teoriyu i nablyudeniya. Vazhno takzhe pravil'no poschitat', chto budet proishodit' vo vneshnih sloyah, gde, vrode by, deistvuet kuda kak bolee ponyatnaya fizika. No ponyatnaya, ne oznachaet prostaya. Mnogie effekty poka uchityvayutsya ochen' ploho. Naprimer, vliyanie magnitnyh polei. Teploprovodnost' vo vneshnih sloyah neitronnoi zvezdy svyazana s elektronami, a na nih magnitnoe pole ochen' dazhe vliyaet. Teploprovodnost' vdol' polya i poperek ochen' raznaya. Iz-za netrivial'noi konfiguracii magnitnogo polya temperatura poverhnosti neitronnoi zvezdy okazyvaet neodnorodnoi: na ekvatore holodnee, na polyuse - goryachee, esli my govorim o dipol'nom pole. No pole mozhet byt' nedipol'nym .... Krome togo, zatuhanie magnitnogo polya budet podogrevat' neitronnuyu zvezdy. V itoge, vse ochen' zaputano. Avtory s pomosh'yu dvumernyh raschetov pytayutsya hotya by chastichno razobrat'sya v etoi situacii.
arxiv:0712.1356
Harakteristiki i obnruzhimost' epohi temnyh vremen i reionizacii s tochki zreniya modelirovaniya
(Character and detectability of the dark ages and the epoch of reionization: the view from the
simulations).
Authors: Ilian Iliev et al. Comments: In Proceedings of From planets to dark energy: the modern radio universe, 5 pages Pryamoe obnaruzhenie epohi "temnyh vremen" i reionizacii odna iz prioritetnyh nauchnyh celei nizkochastotnyh radioinstrumentov, kak deistvuyushih (Giant Metrewave Radio Telescope, 21- CM Array), tak i razrabatyvaemyh (Low Frequency Array, Murchison Widefield Array i Square Kilometre Array). Vsledstvie slabogo i zashumlennogo signala, ozhidaetsya, chto takie nablyudeniya budut kraine slozhny. Uspeh eksperimentov i korrektnoi interpretacii rezul'tatov budet tesno svyazan s ponimaniem osnovnyh processov i harakternyh masshtabov reionizacii, poluchennyh iz chislennyh eksperimentov. V rabote kratko obsuzhdayutsya osnovnye rezul'taty chislennogo modelirovaniya v etoi oblasti. Po ocenke avtorov, optimal'nye nablyudatel'nye chastoty eksperimenta lezhat v diapazone 140-160 MGc.
arxiv:0712.1382
Vzaimosvyaz' mezhdu sistemoi sharovyh skoplenii, roditel'skoi galaktikoi i ee okruzheniem:
primer izucheniya izolirovannoi ellipticheskoi galaktiki NGC 821
(The Connection between Globular Cluster Systems and their Host Galaxy and Environment:
A Case Study of the Isolated Elliptical NGC 821).
Authors: L.R. Spitler et al. Comments: MNRAS, 24 pages Sharovye skopleniya prinadlezhat k samym starym galakticheskim podsistemam, vozrast ih, kak pravilo, prevyshaet 10 mlrd let. Formirovanie skoplenii proishodilo na rannih etapah evolyucii galaktik, i potomu ih svoistva otrazhayut effektivnost' galakticheskoi istorii zvezdoobrazovaniya v zavisimosti ot massy galaktiki, ee morfologii i okruzheniya. Glavnoi cel'yu opisannogo v stat'e proekta stalo issledovanie svoistv sistemy sharovyh skoplenii galaktiki NGC 821, predstavlyayushei soboi izolirovannuyu ellipticheskuyu galaktiku klassa E6. Nablyudeniya NGC 821 v B, V i R fil'trah byli provedeny na 3.5 metrovom teleskope WIYN (Wisconsin Indiana Yale NOAO Telescope), krome togo v rabote byli ispol'zovany arhivnye habblovskie snimki galaktiki v V i I fil'trah. Rezul'taty issledovaniya pokazali, chto sistema sharovyh skoplenii NGC 821 principial'no nichem ne otlichaetsya ot sharovyh skoplenii ellipticheskih galaktik, vhodyashih v sostav plotnyh galakticheskih skoplenii. Dal'neishee sravnenie s sharovymi skopleniyami, prinadlezhashimi drugim 25 galaktikam razlichnyh mass, morfologicheskih klassov i okruzhenii takzhe ne vyyavilo sushestvennyh razlichii. Obshie vyvody avtorov takovy: 1) chislo sharovyh skoplenii, otnormirovannoe na zvezdnuyu massu galaktiki, proporcional'no zvezdnoi masse galaktiki; otnositel'noe chislo sharovyh skoplenii u spiral'nyh galaktik men'she, chem u gigantskih ellipticheskih; 2) chislo sharovyh skoplenii, otnesennoe k barionnoi masse galaktiki, proporcional'no barionnoi masse; 3) svoistva sharovyh skoplenii ne zavisyat ot galakticheskogo okruzheniya; 4) summarnaya massa sharovyh skoplenii proporcional'na masse galo galaktiki; 5) kosvenno podtverzhdeny teoreticheskie predskazaniya o tom, chto lokal'naya epoha reionizacii dlya galaktik raznyh tipov i okruzhenii sushestvenno ne otlichalas'.
Authors: R. Margutti et al. Comments: Accepted by A&A V rentgenovskom izluchenii odnogo iz gamma-vspleskov byla obnaruzhena interesnaya detal'. Avtory stroyat model' i prihodyat k vyvodu, chto eto mozhet byt' liniya nikelya. Esli model' pravil'naya, to, kak chasto byvaet v astrofizike, spektral'nye dannye dadut vozmozhnost' ponyat' ochen'-ochen' mnogo novogo o mehanizme vspleska, o tom, chto proishodilo "vnutri central'noi mashiny". Naprimer, mozhno budet s uverennost'yu govorit' o tom, kogda posle nachala kollapsa proizoshel gamma-vsplesk.
Authors: E.P. Mazets et al. Comments: 15 pages, 5 figures, submitted to ApJ V fevrale etogo goda pribory eksperimenta Konus-Vind, a takzhe drugie detektory, zafiksirovali korotkii zhestkii vsplesk. Po svoim svoistvam on ochen' pohozh na gigantskie vspyshki magnitarov. Prichem, vsplesk proeciruetsya na M31. T.o., vse govorit v pol'zu togo, chto eto vsplesk vnegalakticheskogo istochnika myagkih povtoryayushihsya gamma-vspleskov.
Authors: George Efstathiou Comments: 13 pages, To appear in the proceedings of `A Century of Cosmology', S. Servolo, August 2007, to be published in Il Nuovo Cimento, Nebol'shie kommentarii po nereshennym problemam, kotorye budut atakovany v blizhaishie gody. Spisok vklyuchaet v sebya sleduyushee. Poisk tenzornyh mod (naprimer, po nablyudeniyam polyarizacii relikta). Otvet na vopros o tom, imeem li my delo s kosmologicheskoi postoyannoi, ili zhe velichina ee evolyucioniruet. Razvitie struktury. Podcherknu, chto eto imenno kommentarii, a ne polnocennyi obzor. T.e., nesmotrya na otsutstvie formul chitat' vse eto legko tem, kto v teme.
Authors: pochti dvesti avtorov Comments: 328 pages, 7.8Mb, Proceedings of the 5th SCINEGHE Workshop, June 18-20, 2007 Celikom vylozhen sbornik trudov konferencii, posvyashennoi gamma-astronomii. Na moi vzglyad, eto pravil'nyi put'. Pechatnye "kirpichi" s trudami konferencii vpolne mozhno otmenit'.
Authors: V.L. Afanasiev, V.V. Kalenichenko, I.D. Karachentsev Comments: 9 pages, 6 EPS figures, Astrophysical Bulletin, 2007, v. 62, p. 301-310 28 iyulya 2006 g. na shestimetrovom teleskope v SAO sluchaino byl poluchen spektr slabogo meteora. Neobychnym yavlyaetsya to, chto ocenka skorosti chasticy okazalas' gromadnoi: 300 km v sek. Imenno eto i daet osnovaniya avtoram nazyvaet ego "mezhgalakticheskim", ibo v raione solnechnoi orbity v Galaktike eta velichina prevoshodit "vtoruyu galakticheskuyu". Ocenka razmera chasticy daet vsego lish' neskol'ko desyatyh millimetra, no eto nemalo, esli sravnivat' s analogichnymi chasticami v Solnechnoi sisteme.
Obsudit' v ZhZh-soobshestve
ru_astroph.
Authors: M. Guedel Comments: accepted by The Living Reviews in Solar Physics, 121 pages, 44 figures; Avtor daet detal'nyi obzor togo, chto my znaem ob aktivnosti molodogo Solnca i o ego vozmozhnom vliyanii na formirovanie Solnechnoi sistemy i rannyuyu evolyuciyu planet v nei.
My budem starat'sya hotya by perechislit' interesnye (dlya shirokoi publiki) stat'i, poyavivshiesya v razdele physics (vklyuchaya cross-listing).
Authors: S.F.King Comments: 30 pages, 14 figures, review article suitable for a general audience Avtorskoe zamechanie "suitable for a general audience" sleduet dopolnit' ogovorkoi, chto rech' idet o "fizicheskoi" auditorii. Obzor v samom dele, na moi vzglyad, horosh, no znanii fiziki i matematiki taki trebuet. Sobrany vse osnovnye voprosy, obsuzhdayushiesya v sovremennoi neitrinnoi fizike. Vo mnogih chasto upominaemyh punktah obzor pomozhet fiziku, ne yavlyayushemusya specialistam v blizkih k fizike neitrino oblastyah, razobrat'sya chut' detal'nee, yasnee ponyat' nekotorye momenty.
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