The R.A.P.Project "Prosto o slozhnom" "Astro-ph za pervuyu polovinu 2003 g." Nemnogo statistiki Predydushii vypusk (N56) ANKa Dnya Slovar' astroterminov Spisok missii i teleskopov Obzory UFN Stat'i SOZh ANKa Dnya 20.09.2003. Filamenty mezhdu skopleniyami galaktik 11.09.2003. Obrazovanie dzhetov pri kollapse zvezd Soderzhanie i bystryi perehod k razdelam obzora Stat'i nedeli "Luchshie iz luchshih" astro-ph/0309580 Fazy rentgenovskih i radioimpul'sov pul'sara PSR B1937+21 astro-ph/0309603 Sistematicheskie variacii momentov prihoda impul'sov ot pul'sara PSR B1937+21 - sledy zvezdy-kompan'ona? astro-ph/0309738 Spektroskopiya gravitacionnogo linzirovaniya i ogranicheniya na strukturu temnoi materii v Q2237+0305 astro-ph/0309826 Lozhnye sobstvennye dvizheniya kvazarov po izmereniyam geodezicheskoi seti VLBI Otdel'nye stat'i Netrinno-yadernaya astrofizika sverhnovyh Ob obrazovanii buryh karlikov Rentgenovskoe izluchenie pohozhego na Krab pul'sara PSR J0537-6910 Otkrytie yarkoi sil'no oslablennoi poglosheniem galakticheskoi rentgenovskoi dvoinoi na sputnike INTEGRAL LOFAR - novyi nizkochastotnyi radioteleskop Kollaps yader v treh izmereniyah Algoritm optimal'nogo deleniya dannyh na intervaly Ochistka baz dannyh obzorov neba novymi metodami Fazy rentgenovskih i radioimpul'sov pul'sara PSR B1937+21 Vliyanie dvoistvennosti na dinamiku kollapsa yadra i na skorost' neitronnoi zvezdy Mezhgalakticheskie sharovye skopleniya Sistematicheskie variacii momentov prihoda impul'sov ot pul'sara PSR B1937+21 - sledy zvezdy-kompan'ona? Termoyadernye rentgenovskie vspyshki: teoriya i nablyudeniya Voprosy teorii kollapsiruyushih sverhnovyh Ozhidaemye otkloneniya uskorenii zvezd vokrug sverhmassivnoi chernoi dyry v centre Galaktiki ot Keplerovskih Spektroskopiya gravitacionnogo linzirovaniya i ogranicheniya na strukturu temnoi materii v Q2237+0305 Raspredelenie sverhnovyh tipa Ia po krasnym smesheniyam: ogranicheniya na praroditelei sverhnovyh i na istoriyu zvezdoobrazovaniya O potoke pyli iz-za predelov Solnechnoi sistemy v atmosfere Zemli Gipernovaya (gamma-vsplesk) v centre Galaktiki kak vozmozhnyi istochnik galakticheskih pozitronov Lozhnye sobstvennye dvizheniya kvazarov po izmereniyam geodezicheskoi seti VLBI Polnyi Arhiv predydushih vypuskov. Arhiv statei, voshedshih v vypuski s 01 iyulya 2002 g. po 31 marta 2003 g. Razdely arhiva (s aprelya 2003 g.): kosmologiya, neitrino, kosmicheskie luchi i gamma-astronomiya, galaktiki, AYaG, kvazary, nasha Galaktika, mezhzvezdnaya sreda, zvezdy, sverhnovye, ostatki sverhnovyh, chernye dyry, neitronnye zvezdy, linzirovanie, Solnce, ekzoplanety, Solnechnaya sistema, akkreciya, tesnye dvoinye sistemy, gamma-vspleski, gravitacionnye volny, mehanizmy izlucheniya, chislennoe modelirovanie, dinamika, mehanika metody obrabotki dannyh, MGD, metody nablyudenii, budushie nablyudatel'nye proekty, prochee. Poleznye astronomicheskie ssylki. Korotkoe esse ob elektronnyh preprintah. Obzornye stat'i v astro-ph s 2001 g. Obsudit' na forume Scientific.RU Obsudit' na forume Zvezdocheta Avtory proekta Sergei Popov Mihail Prohorov Postav'te u sebya nashu knopku! Proekt razmeshen na saitah: Vy mozhet takzhe razmestit' na svoem saite nashu lentu obzorov Novostnye lenty Novosti astronomii ot PRAO Tekushie otkrytiya v FECh Novosti kosmonavtiki Novosti ot UFN Informnauka Perst Podpiska na rassylku obzorov na Subscribe.Ru

Obzory preprintov astro-ph Vypusk N57 astro-ph za 22 - 30 sentyabrya 2003 goda: izbrannye stat'i Referaty otdel'nyh statei miniobzor astro-ph/0309519 Netrinno-yadernaya astrofizika sverhnovyh (Supernova Neutrino-Nucleus Astrophysics) Authors: A.B.Balantekin, G.M.Fuller Comments: 12 pages, 4 figures. Kollapsiruyushee yadro massivnoi predsverhnovoi - odin iz samyh moshnyh istochnikov neitrino vo Vselennoi. Kakoe vozdeistvie etot potok mozhet okazat' na yadra atomov v kollapsiruyushem yadre? Kak na etih reakciyah mozhet skazat'sya effekt smeshivaniya neitrino (perehod neitrino odnogo sorta v drugie)? Vot dve osnovnye temy etogo korotkogo obzora. astro-ph/0309520 Ob obrazovanii buryh karlikov (On the Formation of Brown Dwarfs) Authors: Ing-Guey Jiang et al. Comments: 20 pages, 4 figures, accepted by AJ Burye ili korichnevye karliki zanimayut mesto mezhdu zvezdami i planetami-gigantami. Ih massa ne dostatochna dlya togo, chtoby nachalas' reakciya goreniya vodoroda (M<0.075Mo), no bol'she maksimal'noi massy planety-giganta (M>0.075MJ). Oni ochen' holodnye (po sravneniyu so zvezdami), poetomu ih izuchayut v infrakrasnom diapazone, no dazhe tam eto slabye ob'ekty. Izucheniyu buryh karlikov (v tom chisle) byli posvyasheny dva infrakrasnyh obzora neba: DENIS (DEep Near-Infrared Survey) i 2MASS (2 Micron All-Sky Survey). Vopros ob ih formirovanii ochen' interesen: poskol'ku massy buryh karlikov mnogo men'she Dzhinsovskoi, to oni dolzhny byli skoree obrazovyvat'sya v processah vtorichnoi fragmentacii protozvezdnyh oblakov, a ne putem pryamogo kollapsa molekulyarnogo oblaka. Chtoby akkreciya ne uvelichila ih massu, burye karliki dolzhny pokidat' oblasti s vysokoi plotnost'yu veshestva vskore posle svoego formirovaniya. Avtory dannoi raboty predpolagayut, chto bol'shaya chast' korichnevyh karlikov obrazovyvalas' v okolozvezdnyh diskah, t.e. dolzhna vhodit' v sostav shirokih dvoinyh sistem. astro-ph/0309523 Rentgenovskoe izluchenie pohozhego na Krab pul'sara PSR J0537-6910 (The X-ray emission of the Crab-like pulsar PSR J0537-6910) Authors: T. Mineo, G. Cusumano, E. Massaro Comments: 4 pages, 2 figures Rentgenovskii pul'sar PSR J0537-6910 ochen' pohozh na pul'sar v krabovidnoi tumannosti, tol'ko ego period sostavlyaet 16 ms (u Kraba - 33 ms). Eto samyi bystryi pul'sar associiruyushiisya s ostatkom sverhnovoi. Krome togo v nem proishodyat chastye i ochen' sil'nye glitchi (skachkoobraznye izmeneniya - "sboi" - perioda vrasheniya). Spektr i profil' rentgenovskogo izlucheniya v diapazone energii 0.1-30 keV vosstanovleny po arhivam BeppoSAX i RossiXTE. Rentgenovskii profil' impul'sa pul'sara PSR J0537-6910 astro-ph/0309536 Otkrytie yarkoi sil'no oslablennoi poglosheniem galakticheskoi rentgenovskoi dvoinoi na sputnike INTEGRAL (INTEGRAL discovery of a bright highly obscured galactic X-ray binary source IGR J16318-4848) Authors: R. Walter et al. Comments: 6 pages, 4 figures (fig 1 quality lowered), accepted for publication in A&A letters (INTEGRAL special issue) Kogda s pomosh'yu kakogo-libo sputnika otkryvayutsya novye istochniki, no v nazvanii ob'ekta prisutstvuet abbreviatura pribora (sm. takzhe voobshe poleznyi spisok sokrashenii). Naprimer: GRS - GRANAT, E - Einstein, RX - ROSAT, GS - GINGA .... Vot stali poyavlyat'sya istochniki s IGR - INTEGRAL. IGR J16318-4848 - eto dvoinaya sistema s akkreciruyushim kompaktnym ob'ektom (neitronnoi zvezdoi ili chernoi dyroi). Ranee etot istochnik ne videli iz-za sil'nogo poglosheniya. No INTEGRAL rabotaet v dostatochno zhestkom diapazone, a tam pogloshenie ne stol' sushestvenno. astro-ph/0309537 LOFAR - novyi nizkochastotnyi radioteleskop (LOFAR, a new low frequency radio telescope) Authors: H. J. A. Rottgering Comments: 6 Pages, 1 figure LOFAR - massiv primerno 100 nizkochastotnyh antenn, kazhdaya razmerom s futbol'noe pole, budet razmeshen na uchastke 400x400 km na poberezh'e Gollandii. Teleskop budet rabotat' na chastotah ot 10 do 240 MGc. Na verhnei granice chastoty uglovoe razreshenie instrumenta budet luchshe odnoi uglovoi sekundy. Razmeshenie antenn teleskopa LOFAR astro-ph/0309539 Kollaps yader v treh izmereniyah (3-Dimensional Core-Collapse) Authors: C. L. Fryer and M. S. Warren Comments: 34 pages (5 of 17 figures missing), accepted by ApJ Eta stat'ya - prazdnik trehmernyh raschetov, kotorye byli vypolneny dlya serii modelei s razlichnoi skorost'yu vrasheniya i magnitnym polem. Samoe bystroe iz rassmotrennyh vrashenii ne privodit k fragmentacii zvezdy i ne vyzyvaet sushestvennyh izmenenii v processah konvekcii v centre ee yadra. Analogichno, rassmatrivalis' ne slishkom sil'nye magnitnye polya, kotorye ne dominiruyut v processe vzryva sverhnovoi (bolee sil'nye magnitnye polya, nablyudaemye u neitronnyh zvezd, mogut voznikat' pri ih posleduyushem ohlazhdenii i szhatii). V modeli s samym bystrym vrasheniem mozhet obrazovat'sya pul'sar, energii vrasheniya kotorogo budet dostatochno dlya sbrosa obolochki sverhnovoi. No sovremennye evolyucionnye teorii predskazyvayut slishkom medlennoe vrashenie u predsverhnovyh, chtoby takoi (magnitorotacionnyi) mehanizm mog srabotat'. math.NA/0309285 Algoritm optimal'nogo deleniya dannyh na intervaly (An Algorithm for Optimal Partitioning of Data on an Interval) Authors: Brad Jackson et al. Comments: 4 pages, 1 figure, submitted to IEEE Signal Processing Letters Pravil'no razdelit' nablyudatel'nye dannye na intervaly, chtoby zatem ih udachno approksimirovat' - pochti iskusstvo. V dannoi zametke opisan prostoi, no moshnyi algoritm, kotoryi prosmatrivaet vse vozmozhnye varianty razbieniya N tochek dannyh za vremya poryadka N2 (obrashaem vnimanie, chto obshee chislo variantov razbieniya proporcional'no eN). Algoritm garantirovanno nahodit global'nyi optimum i avtomaticheski opredelyaet chislo intervalov na kotoroe nado razbit' ishodnye dannye. Algoritm legko obobshaetsya na mnogomernye dannye. Vozmozhna, takzhe, ego rabota v real'nom vremeni. Primer razbieniya nabora dannyh na intervaly astro-ph/0309565 Ochistka baz dannyh obzorov neba novymi metodami (Cleaning sky survey databases using Hough Transform and Renewal String approaches) Authors: A.J. Storkey et al. Comments: 17 pages, Accepted for MNRAS. Bazy dannyh bol'shih obzorov neba (naprimer, SuperCOSMOS Sky Survey, SSS), takzhe kak i otdel'nye nablyudeniya, "zasoryayutsya" proletami iskusstvennyh sputnikov i samoletov, fizicheskimi defektami priemnikov (segodnya eto, v osnovnom, PZS) i t.d. Odnako, esli poyavlenie podobnyh defektov v odinochnyh nablyudeniyah mozhno obnaruzhit' i, po vozmozhnosti, ustranit' v ruchnuyu, to v avtomaticheski provodimyh obzorah bol'shogo ob'ema takoe reshenie nevozmozhno. Dannaya stat'ya posvyashena obnaruzheniyu i udaleniyu iz dannyh obzorov "trekov" iskusstvennyh sputnikov zemli i samoletov i drugih lineinyh defektov. Polnuyu versiyu stat'i (s risunkami) mozhno vzyat' na saite avtorov http://www.anc.ed.ac.uk/~amos/publications.html, a detali proekta uznat' zdes'. astro-ph/0309580 Fazy rentgenovskih i radioimpul'sov pul'sara PSR B1937+21 (The phase of the radio and X-ray pulses of PSR B1937+21) Authors: G. Cusumano et al. Comments: 5 pages, 2 figures, accepted A&A Lett. Pul'sar PSR B1937+21 - samyi bystryi izvestnyi millisekundnyi pul'sar s periodom 1.56 ms. On nablyudalsya v rentgene (na BeppoSAX i RXTE) i v radio (na teleskope v Effel'sberge). V oboih diapazonah profil' impul'sa obladaet dvumya pikami. Rentgenovskie impul'sy nemnogo otstayut ot radio, primerno na 50 mikrosekund. Zato s centrami rentgenovskih impul'sov ochen' tochno sovpadayut tak nazyvaemye gigantskie radioimpul'sy vremya ot vremeni voznikayushie na etom pul'sare. Takoe sovpadenie ukazyvaet, chto rentgenovskoe izluchenie i gigantskie radioimpul'sy generiruyutsya v odnoi i toi zhe oblasti magnitosfery pul'sara. Profili impul'sov pul'sara PSR B1937+21. Vverhu - rentgenovskie dannye RXTE (shirina bina - 16 mikrosekund), v seredine - rentgenovskie dannye BeppoSAX, vnizu - radioimpul'sy. Strelkami pokazany mesta poyavleniya gigantskih radioimpul'sov. astro-ph/0309588 Vliyanie dvoistvennosti na dinamiku kollapsa yadra i na skorost' neitronnoi zvezdy (The Effects of Binary Evolution on the Dynamics of Core Collapse and Neutron-Star Kicks) Authors: Ph. Podsiadlowski et al. Comments: 7 pages, 3 figures, submitted to ApJ Naibolee mnogochislennye sverhnovye, soglasno zakonu Solpitera, obrazuyutsya iz zvezd s massami okolo 10 Mo. Odnako, ih evolyuciya v odinochnyh i dvoinyh sistemah zametno razlichaetsya. V konce evolyucii v dvoinyh zvezdah s nachal'noi massoi >11 Mo obrazuetsya men'shee zheleznoe yadro, chem v odinochnyh. Zvezdy s massoi 8-11 Mo v dvoinyh sistemah vyzyvayut vzryvy sverhnovyh (kollaps yadra vyzyvaetsya reakciyami elektronnogo zahvata), a odinochnye sistemy takoi massy prevrashayutsya v tyazhelye O-Ne-Mg belye karliki. Estestvennym obrazom voznikayut dve gruppy zvezd: evolyucionirovavshih v tesnyh dvoinyh i odinochnye ili shirokie pary. Vzryvy sverhnovyh pervoi gruppy soprovozhdayutsya men'shei otdachei i, kak sledstvie, porozhdayut neitronnye zvezdy s malymi prostranstvennymi skorostyami. [Prim.: Konechno, vse eti zaklyucheniya trebuyut dopolnitel'noi proverki.] astro-ph/0309602 Mezhgalakticheskie sharovye skopleniya (Intergalactic Globular Clusters) Authors: Michael J. West et al. Comments: 2 pages, no figures. Talk presented at JD6, IAU General Assembly XXV, Sydney, Australia, July 2003, to appear in Highlights of Astronomy, Vol. 13 Est' vse osnovaniya polagat', chto sharovye skopleniya mogut sushestvovat' ne tol'ko vokrug materinskih galaktik, no i samostoyatel'no. V eto kraine korotkoi (po suti odnostranichnoi) zametke avtory soobshayut o tom, chto oni nashli novye podtverzhdeniya togo, chto vydelennyi imi ob'ekt yavlyaetsya takim odinochnym sharovym skopleniem. astro-ph/0309603 Sistematicheskie variacii momentov prihoda impul'sov ot pul'sara PSR B1937+21 - sledy zvezdy-kompan'ona? (Systematic variation of the residual of PSR B1937+21, the trace of its companion star?) Authors: B.P.Gong Comments: 15 pages, 6 tables, 3 figures PSR B1937+21 - pervyi otkrytyi millisekundnyi pul'sar. Do sih por schitalos', chto on odinochnyi. Odnako dlitel'nye nablyudeniya pokazali, chto momenty prihoda impul'sov ot nego ispytyvali sistematicheskie variacii. Odno iz ob'yasnenii - pul'sar PSR B1937+21 vhodit v dvoinuyu sistemu s kompan'onom massoi okolo 0.01 Mo, orbital'nym periodom poryadka 0.1 dnya, raspolozhennuyu otnositel'no nam "plashmya" s ochen' vysokoi tochnost'yu - vtoroi kompan'on peremeshaetsya po luchu zreniya na 10-4-10-3 svetovoi sekundy (30-300 km). V etom sluchae radial'noe dvizhenie samogo pul'sara pri segodnyashnei tochnosti izmerenii voobshe ne obnaruzhivaetsya. Nablyudaemye otkloneniya momentov prihoda impul'sov svyazany s orbital'noi precessiei neitronnoi zvezdy, os' vrasheniya kotoroi naklonena k ploskosti orbity. Otkloneniya momentov prihoda impul'sov pul'sara PSR B1937+21 ot ozhidaemyh srednih znachenii za 1984-1993 gg. [Prim.: Eshe odnim ob'yasneniem nablyudaemyh yavlenii mozhet byt' svobodnaya precessiya pul'sara.] miniobzor astro-ph/0309626 Termoyadernye rentgenovskie vspyshki: teoriya i nablyudeniya (Thermonuclear X-ray Bursts: Theory vs. Observations) Authors: Andrew Cumming (University of California, Santa Cruz) Comments: 11 pages, 6 figures Veshestvo, akkreciruyushee na neitronnuyu zvezdu, postepenno nakaplivaetsya na ee poverhnosti, uplotnyaetsya i v nem mogut nachat'sya termoyadernye reakcii. Gorenie etogo veshestva obychno idet vzryvnym obrazom - front plameni za neskol'ko sekund probegaet po vsei poverhnosti neitronnoi zvezdy. Pohozhie processy mogut proishodit' i na medlenno akkreciruyushih belyh karlikah, no tam sovsem drugie plotnosti i temperatury veshestva. astro-ph/0309653 Propan na Titane (Propane on Titan) Authors: H.G.Roe et al. Comments: accepted to ApJL 18 September 2003 V atmosfere sputnika Saturna Titana vpervye obnaruzhen propan (C3H8). Spektral'nye linii izlucheniya propana prishlos' vydelyat' sredi mnozhestva drugih stratosfernyh linii - eto ochen' slozhnaya spektrometricheskaya zadacha s kotoroi prekrasno spravilis' amerikanskie astronomy. astro-ph/0309684 Voprosy teorii kollapsiruyushih sverhnovyh (Topics in Core-Collapse Supernova Theory) Authors: Adam Burrows et al. Comments: 10 pages, 2 figures Celyi ryad interesnyh tem, v kotoryh perepletayutsya fizika i astrofizika, my nazyvaem "Teoriei Sverhnovyh". V dannoi stat'e avtor uspel kosnut'sya chetyreh iz nih: Otkuda u pul'sarov vysokie prostranstvennye skorosti? Gravitacionnye volny ot kollapsa yadra. Vzryv sverhnovoi i ee vrashenie. Otkuda beretsya energiya Sverhnovoi? astro-ph/0309716 Ozhidaemye otkloneniya uskorenii zvezd vokrug sverhmassivnoi chernoi dyry v centre Galaktiki ot Keplerovskih (Apparent Deviations from Keplerian Acceleration for Stars Around the Supermassive Black Hole at the Galactic Center) Authors: Abraham Loeb (Harvard) Comments: 5 pages, submitted to Phys. Rev. D My uzhe pisali o zvezdah vblizi central'noi chernoi dyry nashei Galaktiki (sm. naprimer zdes'). Odnako, gravitacionnoe pole chernoi dyry otlichaetsya ot polya material'noi tochki ili sfericheski-simmetrichnogo tela, ono opisyvaetsya metrikoi Shvarcshil'da (a esli chernaya dyra vrashaetsya, to metrikoi Kerra). Uskoreniya, s kotorymi dvizhutsya zvezdy, budut neskol'ko otlichat'sya ot Keplerovskih znachenii, prichem tem sil'nee, chem blizhe zvezda nahoditsya k chernoi dyre. Eto budet proyavlyat'sya v izmeneniyah luchevyh skorostei zvezd - ochen' tochno izmeryaemoi nablyudatel'noi velichiny. Dlya zvezd priblizhayushihsya k chernoi dyre na rasstoyanie poryadka 100 astronomicheskih edinic otkloneniya mogut sostavit' neskol'ko procentov. Effekty takoi velichiny mozhno budet obnaruzhit' vsego cherez neskol'ko let nablyudenii. astro-ph/0309744 Zondirovanie prostranstva-vremeni vokrug Sgr A* s pomosh'yu radiopul'sarov (Probing the Spacetime Around Sgr A* with Radio Pulsars) Authors: Eric Pfahl, Avi Loeb (CfA) Comments: 6 pages Stat'ya primerno na tu zhe temu, chto i predydushaya astro-ph/0309716 (odin iz avtorov - tozhe). Vokrug central'noi chernoi dyry Mlechnogo Puti (ob'ekta Sgr A*) letayut zvezdy s massami 10-20 Mo. Chem zakanchivaetsya ih evolyuciya? Vzryvami sverhnovyh s obrazovaniem neitronnyh zvezd, kotorye pervye neskol'ko millionov let proyavlyayut sebya kak radiopul'sary. A radiopul'sary - samye tochnye chasy v kosmose! Ocenki pokazyvayut, chto vokrug Sgr A* dolzhno byt' okolo 1000 radiopul'sarov s periodom obrasheniya men'shim 100 let. Nekotorye iz nih mozhno budet obnaruzhit' na chastotah ~10 GGc, gde maly effekty mezhzvezdnogo rasseyaniya. Esli eto udastsya sdelat', to my ochen' mnogo uznaem o nashei chernoi dyre, vklyuchaya effekty svyazannye s ee vrasheniem. astro-ph/0309738 Spektroskopiya gravitacionnogo linzirovaniya i ogranicheniya na strukturu temnoi materii v Q2237+0305 (Spectroscopic Gravitational Lensing and Limits on the Dark Matter Substructure in Q2237+0305) Authors: R.B. Metcalf et al. Comments: 29 pages, 16 figures, submitted to ApJ Ochen' podrobno s primerami iz nablyudenii gravitacionnoi linzy s chetyr'mya izobrazheniyami Q2237+0305 pokazano chego mozhno dobit'sya, esli vmesto postroeniya fotometricheskoi karty (raspredeleniya yarkosti) provodit' prostranstvenno-razreshennuyu spektroskopiyu (t.e. v kazhdoi tochke izobrazheniya stroit' spektr ili, chto to zhe samoe, stroit' nabor izobrazheniya linzy na raznyh dlinah voln). Metod okazyvaetsya ochen' effektivnym: udaetsya izbezhat' situacii vyrozhdennoi zavisimosti ot parametrov, kotoraya chasto vstrechalas' v etoi oblasti astrofiziki. Naprimer, koefficienty usileniya izlucheniya iz oblasti uzkih linii i iz oblasti shirokih linii kvazara zametno razlichayutsya, oni takzhe ne sovpadayut s koefficientami dlya infrakrasnogo i radio diapazonov. Dlya ob'ekta Q2237+0305 polucheny ogranicheniya na raspredelenie v nem temnoi materii. Izobrazheniya linzirovannogo kvazara Q2237+0305 v linii H (sleva) i v zapreshennoi linii dvazhdy ionizovannogo kisloroda 5007A (sprava). astro-ph/0309796 Raspredelenie sverhnovyh tipa Ia po krasnym smesheniyam: ogranicheniya na praroditelei sverhnovyh i na istoriyu zvezdoobrazovaniya (The Redshift Distribution of Type-Ia Supernovae: Constraints on Progenitors and Cosmic Star Formation History) Authors: Avishay Gal-Yam and Dan Maoz Comments: 9 pages, 7 figures, MNRAS, accepted Proekty poiska dalekih sverhnovyh vedutsya uzhe neskol'ko let, zaregistrirovano neskol'ko desyatkov takih sobytii (0.3<z<1) - teper' mozhno pristupit' k statisticheskoi obrabotke vsego mnozhestva zaregistrirovannyh yavlenii. V dannoi rabote byl vypolnen sleduyushii analiz - dlya razlichnyh empiricheskih zakonov zvezdoobrazovaniya vo Vselennoi (pokazannyh na risunke) byla ocenena zaderzhka mezhdu obrazovaniem zvezdy, iz kotoroi voznikla sverhnovaya, i momentom vzryva. Dazhe v obshem sluchae etot interval okazyvaetsya dovol'no velik: poryadka ili bolee 1 mlrd.let, dlya zakona zvezdoobrazovaniya Madau poluchaetsya ocenka >1.7 mlrd.let (na 95% urovne znachimosti), dlya zakona Lancetta v kotorom zvezdoobrazovanie na bol'shih z sushestvenno vyshe - >2.5 mlrd.let. Empiricheskie zakony zvezdoobrazovaniya vo Vselennoi: (sleva) zakon Madau - maksimal'nyi temp zvezdoobrazovaniya prihoditsya na z=1.5-2; (v centre) zakon Lancetta - temp zvezdoobrazovaniya rastet s z, do z~2 - bystro, zatem - medlennee; (sprava) zakon Kovi-Steidelya s postoyannym tempom zvezdoobrazovaniya pri z>2. Eshe odna stat'ya teh zhe avtorov na blizkuyu temu: astro-ph/0309797 Chastota vspyshek sverhnovyh tipa Ia v skopleniyah galaktik pri z<1: prilozhenie k proishozhdeniyu sverhnovyh i istochnikam zheleza v skopleniyah (The Type-Ia Supernova Rate in z < 1 Galaxy Clusters: Implications for Progenitors and the Source of Cluster Iron) obzor astro-ph/0309805 O potoke pyli iz-za predelov Solnechnoi sistemy v atmosfere Zemli (On the Flux of Extra-Solar Dust in Earth's Atmosphere) Authors: Norman Murray et al. Comments: 62 pages, 8 figures, appear in ApJ Ogromnyi obzor - pervyi za dolgoe vremya po dannomu voprosu. Pylinki mikronnogo razmera, vletayushie v Solnechnuyu sistemu, registriruyutsya iskusstvennymi sputnikam. Sledy sgoraniya bolee krupnyh chastic v atmosfere obnaruzhivayut radary (v Aresibo i v Novoi Zelandii). A sam obzor posvyashen vozmozhnoi prirode i istochnikam takih pylinok. astro-ph/0309824 Gipernovaya (gamma-vsplesk) v centre Galaktiki kak vozmozhnyi istochnik galakticheskih pozitronov (Hypernovae/GRB in the Galactic Center as possible sources of Galactic Positrons) Authors: M. Casse et al. Comments: 9 pages, 0 figures, submitted ApJ Lett Pribory, ustanovlennye na observatorii INTEGRAL, zaregistrirovali sil'noe i protyazhennoe izluchenie vyzvannoe annigilyaciei pozitronov i elektronov v oblasti baldzha Mlechnogo Puti. Nalichie stol' sushestvennogo izbytka pozitronov trebuet svoego ob'yasneniya. Odno iz vozmozhnyh: nekotoroe vremya nazad v central'noi oblasti nashei Galaktiki (ne obyazatel'no v samom centre) proizoshla vspyshka gipernovoi, soprovozhdavshayasya gamma-vspleskom. astro-ph/0309826 Lozhnye sobstvennye dvizheniya kvazarov po izmereniyam geodezicheskoi seti VLBI (Quasar Apparent Proper Motion Observed by Geodetic VLBI Networks) Authors: D. S. MacMillan Comments: 5 pages, 4 figures My uzhe pisali (sm. obzor N56), chto s pomosh'yu sistemy VLBI provodyatsya regulyarnye geodezicheskie (geodinamicheskie) izmereniya. Oni vedutsya s 1979 goda, a s 1990 eta programma prinyala sleduyushii vid: 2-3 raza v nedelyu provodyatsya 24-chasovye geodezicheskie sessii nablyudenii v kotoryh zadeistvovany ot 4 do 7 antenn seti VLBA (nacional'noi amerikanskoi VLBI) i v techenii takoi sessii nablyudaetsya 40-50 istochnikov (kvazarov). Okazalos', chto po dannym geodezicheskih sessii za 1979-2003 gg. u bol'shogo chisla kvazarov est' znachimye nenulevye sobstvennye dvizheniya: u 580 istochnikov tochnosti opredeleniya sobstvennyh dvizhenii sostavlyayut 0.5 mas/god i luchshe (eti ob'ekty pokazany na risunke), a dlya 50-60 ob'ektov ih sobstvennye dvizheniya otlichayutsya ot nulya bolee, chem na 3. 580 kvazarov, ch'i sobstvennye dvizheniya izmereny s tochnost'yu luchshe, chem 0.5 mas/god. (Bukva "u" na risunke zamenyaet ). Konechno, eti sobstvennye dvizheniya iskusstvennye. Ukazaniyami na eto sluzhat otsutstvie zavisimosti sobstvennyh dvizhenii ot krasnyh smeshenii kvazarov (t.e. ot rasstoyanii do nih) i nelineinoe izmenenie polozheniya istochnikov so vremenem (sm. dva sleduyushih risunka). Grafik: velichina sobstvennyh dvizhenii kvazarov - krasnoe smeshenie. Samyi dalekii kvazar s nenulevym sobstvennym dvizheniem nahoditsya na z=4.3. Vidno otsutstvie zavisimosti -z. Izmenenie pryamogo voshozhdeniya kvazara 4S39.25 so vremenem. Prichina dannogo yavleniya ne vpolne yasna. Skoree vsego ono svyazano s izmeneniem struktury izluchayushih ob'ektov ili geometrii seti antenn. Vernut'sya k nachalu stranicy

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