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21.02.03. astro-ph za 17 - 21 fevralya 2003 goda: izbrannye stat'i |
Authors: A. M. Ghez et al.
Authors: F. Mannucci et al.
Authors: E. B. Fomalont, S. M. Kopeikin
Authors: Erik Kuulkers, Andrew Norton, Axel Schwope, Brian Warner
Authors: P.D. Barthel, I.M. van Bemmel Commets: 9 pages, no figures, in Proceedings Radio Galaxy Workshop, Leiden, 11-15 November 2002 Obsuzhdaetsya status edinyh modelei vnegalakticheskih radioistochnikov. Osoboe vnimanie udelyaetsya svoistvam pyli. V edinyh modelyah razlichnye tipy AYaG ob'yasnyayutsya v ramkah akkrecii na sverhmassivnuyu chernuyu dyry. Razlichie proyavlenii opredelyaetsya raznoi massoi dyry, raznym tempom akkrecii, raznoi orientaciei dzheta po otnosheniyu k nablyudatelyu i raznymi svoistvami sredy vblizi dyry i dzheta (otsyuda vazhnost' ucheta pyli). Obzor korotkii, no privodyatsya ssylki na bol'shie obzornye stat'i po raznym aspektam edinoi modeli.
Authors: R. Salvaterra, A. Ferrara Commets: 5 pages, 2 figures. Accepted for publication on MNRAS Kolichestvo geliya, sintezirovannogo na stadii pervichnogo nukleosinteza v rannei Vselennoi, mozhet byt' "zamaskirovano" vybrosom geliya ot zvezd pervogo pokoleniya (populyacii III). Smotri takzhe astro-ph/0302316.
Authors: E. B. Fomalont & S. M. Kopeikin V novoi stat'e v pervuyu ochered' detal'no opisyvaetsya eksperiment i rezul'taty izmerenii. Odnako, est' i razdel "diskussiya", gde "kratko i myagko" obsuzhdaetsya interpretaciya poluchennyh rezul'tatov: t.e. perechislyayutsya vozrazheniya, privodyatsya ssylki na nih i na otvety, a takzhe delaetsya sushestvenno bolee myagkoe utverzhdenie, chto "osnovnoi interpretaciei eksperimenta yavlyaetsya soglasie rezul'tatov s predskazaniyami OTO".
Authors: David Merritt (Rutgers) and M. Y. Poon (Harvard) Commets: 26 pages, 5 figures, uses aastex.sty Esli v centre galaktiki sidit chernaya dyra, to te zvezdy, kotorye mogli byt' ei bystro zahvacheny, uzhe ei poglosheny. Teper' (v kvazistacionarnoi situacii) zahvatyvayutsya zvezdy, ch'i orbity prolegayut ryadom s granicei zahvata (konusa poter') i peresekayut ego iz-za vneshnih vozmushenii. Temp akkrecii (zahvata zvezd) v takoi situacii mal, kak i svetimost' chernoi dyry. Situaciya izmenyaetsya, esli gravitacionnyi potencial vblizi centra galaktiki ne obladaet osevoi simmetriei (naprimer, yavlyaetsya trehosnym) ili/i zvezdy dvizhutsya haoticheskim obrazom (sm. nizhe stat'yu o haoticheskih yavleniyah).
Authors: A. M. Ghez et al. Commets: 14 pages, Latex, Accepted for Publication in ApJ Letters Vpervye udalos' zaregistrirovat' spektral'nye (absorbcionnye) linii ot zvezdy, vrashayusheisya ochen' blizko ot "nashei" sverhmassivnoi chernoi dyry. Zvezda okazalas' massivnoi (M poryadka 15 mass Solnca). Dovol'no molodoi: ona eshe nahoditsya na glavnoi posledovatel'nosti. Eto paradoksal'nyi rezul'tat, t.k. schitalos', chto tak blizko ot chernoi dyry, gde prilivnye sily ochen' veliki, zvezdy ne obrazuyutsya. krome togo, vremya migracii zvezdy na takuyu orbity (esli ona rodilas' tam, gde prilivy slabee) bol'she vremeni zhizni stol' massivnoi zvezdy. Avtory obsuzhdayut razlichnye idei, pozvolyayushie ob'yasnit' takoi fenomen. Naprimer, "reinkarnaciyu" zvezdy posle sliyaniya (dve slivshiesya nebol'shie zvezdy mogut posle sliyaniya vyglyadet' kak massivnyi ob'ekt). Vozmozhny i drugie ob'yasneniya, svyazannye s vysokoi plotnost'yu zvezd v etoi oblasti, a znachit s vysokoi veroyatnost'yu ih vzaimodeistviya.
Srazu neskol'ko rabot raznyh avtorov po slivayushimsya kompaktnym ob'ektam. Pervaya i tret'ya stat'i posvyasheny chislennym raschetam sliyanii. Vo vtoroi stat'e spiska rassmatrivaetsya vnutrennee stroenie neitronnyh zved. V chetvertoi - izuchayutsya nekotorye teorfizicheskie aspekty sliyanii. V pyatoi avtory pytayutsya ob'yasnit' bimodal'nost' raspredeleniya nachal'nyh skorostei neitronnyh zvezd raznymi mehanizmami priobreteniya skorosti.
Authors: Toshikazu Shigeyama, Takuji Tsujimoto, and Yuzuru Yoshii Commets: 4 pages, 5 figures, to appear in The Astrophysical Journal Letters Kak pervoe pokolenie zvezd, rodivsheesya iz "chistogo" kosmologicheskogo veshestva, obogashalo okruzhayushuyu sredu tyazhelymi (tyazhelee He) elementami? Smotri takzhe astro-ph/0302285.
Authors: F. Mannucci et al. Commets: A&A, in press, 13 pages Kak izvestno, v nashei galaktike sverhnovye ne nablyudalis' poslednie 400 let. I eto pri tempe vspyshek poryadka odnoi v 30 let! Ob'yasnenie prostoe - vspyhivayut daleko i zakryty pyl'yu. T.e. nesmotrya na potryasayushuyu moshnost' vzryva ego taki mozhno nezametit'. Pohozhaya kartina proishodit i v drugih galaktikah. Pravda, tam my redko vidim galaktiku s rebra, kak v sluchae Mlechnogo Puti, v ploskosti kotorogo my nahodimsya. Tem ne menee v galaktikah s burnym zvezdoobrazovaniem, gde dolzhno byt' mnogo sverhnovyh, mnogo i pyli. Poetomu interesno smotret' v IK diapazone, gde pyl' ne tak meshaet. Avtory predstavlyayut rezul'taty svoih issledovanii. Po nablyudeniyam 46 yarkih IK galaktik na dline volny 2.2 mikrona bylo otkryto 4 sverhnovye. Etot temp vspyshek primerno na poryadok prevoshodit temp opticheski zaregistrirovannyh vspyshek (otmetim, chto oshibki vse-taki veliki, t.k. statistika mala). Prichem, ozhidalos' eshe bol'she vspyshek. Znachit, kakie-to sverhnovye vse-taki "nagluho" zakryty pyl'yu....
Authors: Kailash C. Sahu (Space Telescope Science Institute) Commets: 15 pages, including 4 figures. To appear in the Proceedings of the STScI Symposium on "Dark Universe: Matter, Energy, and Gravity" Iz 17 sobytii mikrolinzirovaniya, zaregistrirovannyh v napravlenii Magellanovyh Oblakov, dlya 4 izvestna ocenka rasstoyaniya do linzy i vo vseh etih sluchayah linzy nahodilis' v Magellanovyh Oblakah, a ne v Mlechnom Puti. Massy linz, esli oni raspolozheny v nashei Galaktike lezhat v intervale 0.5-2Mo, dlya Magellanovyh Oblakov - okolo 0.2Mo. Vklad linz v nevidimoe veshestvo - ot 0 do 5%.
Authors: G.S. Busswell, T. Shanks, P.J. Outram, W.J. Frith, N. Metcalfe, R. Fong Commets: 15 pages, 17 figures
V raspredelenii galaktik po dannym poslednih CCD-obzorov naidena "dyra"
(v severnom polusharii primerno na z=0.1). Mnogo kartinok. Etomu zhe posvyashena
sleduyushaya stat'ya:
Authors: J.-F. Le Borgne et al. Commets: 20 pages, accepted for publication in Astronomy and Astrophysics STELIB, novaya spektroskopicheskaya biblioteka, dostupna po adresu http://webast.ast.obs-mip.fr/stelib. V nei 249 spektrov zvezd v vidimom diapazone (ot 3200 do 9500A) so spektral'nym razresheniem ~3A. V biblioteke zvezdy raznyh spektral'nyh klassov i metallichnostei. Tochnost' fotometrii primerno 3%.
Authors: Lifan Wang, Gerson Goldhaber, Greg Aldering, Saul Perlmutter (LBNL) Commets: ApJ, in press Vnimatel'noe rassmotrenie pochti lineinogo povedeniya krivyh bleska Sverhnovyh tipa Ia na diagramme cvet-zvezdnaya velichina (B - B-V ili B-R, ili B-I) pozvolyaet luchshe uchityvat' pogloshenie ih izlucheniya i proizvodit' korrekciyu ih svetimosti. Eto dostatochno sushestvenno, t.k. imenno eti sverhnovye sluzhili "standartnymi svechami" po kotorym opredelili, chto nasha Vselennaya rasshiryaetsya uskorenno.
Authors: Yousaf Butt et al. Commets: 40 pages Schitaetsya, chto osnovnaya dolya galakticheskih kosmicheskih luchei uskoryaetsya v ostatkah sverhnovyh. Odnako, uskoritelyami takzhe mogut yavlyat'sya i obolochki (i sverhobolochki), obrazuemye associaciyami molodyh zvezd. Otnositel'no nedaleko ot nas raspolagaetsya krupneishaya iz izvestnyh v Galaktike associacii - Cyg OB2. Razumeetsya, eto pervyi kandidat v "uskoriteli". Gamma-teleskop HEGRA soobshil ob otkrytii Tevnogo istochnika, sovpadayushego s etoi gruppoi molodyh zvezd. V stat'e opisyvayutsya rentgenovskie i radio nablyudeniya istochnika. Rezul'taty nablyudenii podtverzhdayut gipotezu o svyazi istochnika gamma-izlucheniya s massivnymi zvezdami (tochnee s vzaimodeistviem ih vetrov). V rabote privoditsya ochen' horoshee vvedenie, kotorye my vsem rekomenduem prochest'.
Authors: Alessandro B. Romeo, Cathy Horellou, Joeran Bergh Commets: Mon. Not. R. Astron. Soc., in press. The interested reader is strongly recommended to ignore the low-resolution Fig. 3 (and Fig. 4), and to download the full-resolution paper (700 kb) from http://www.oso.chalmers.se/~romeo/Paper_VI.ps.gz
Avtory opisyvayut metodiku "sglazhivaniya" shumov pri raschetah metodom mnogih tel,
pozvolyayushuyu dobit'sya rezul'tatov, identichnyh uvelicheniyu chisla chastic na dva
poryadka. Sam algoritm v dannoi stat'e detal'no ne opisyvaetsya (budet otdel'naya
publikaciya).
Authors: K.Omukai, F.Palla Commets: 34 pages, 12 figures. ApJ, in press Samye pervye zvezdy obrazovyvalis' iz veshestva. gde bylo ochen' malo t.n. "metallov" - elementov tyazhelee geliya. V processe rozhdeniya i evolyucii takih ob'ektov eshe ochen' mnogo neyasnogo, a ih rol' v astrofizike ochen' velika (sm. nedavnie rezul'taty sputnika WMAP o rannei reionizacii Vselennoi). V stat'e rassmatrivaetsya akkreciya gaza v processe obrazovaniya pervyh zvezd.
Authors: Erik Kuulkers, Andrew Norton, Axel Schwope, Brian Warner Commets: 40 pages, 10 figures. To appear in Compact Stellar X-Ray Sources, eds. W.H.G. Lewin and M. van der Klis, Cambridge University Press
Kataklizmicheskie peremennye - eto tesnye dvoinye sistemy, gde kompaktnym
ob'ektom yavlyaetsya belyi karlik. V obzore rassmatrivaetsya rentgenovskoe
izluchenie etih istochnikov.
Authors: G. K. Skinner Commets: To be published in Proceedings of the 22nd Moriond Astrophysics Meeting "The Gamma-Ray Universe", May 2002 Eds. A. Goldwurm, D. Neumann and J. Tran Thanh Van, The Gioi Publishers (Vietnam) Eto obzor po teorii postroeniya izobrazhenii instrumentami (teleskopami) s kodiruyushimi maskami, kotorye shiroko ispol'zuyutsya v zhestkom rentgenovskom i gamma-diapazonah. Avtor utverzhdaet, chto eta teoriya ochen' prosta, slozhnosti poyavlyayutsya tol'ko pri rabote s real'nymi instrumentami. Rassmotreny instrumenty, ustanovlennye na observatorii INTEGRAL.
Authors: D. L. Kaplan, S. R. Kulkarni, M. H. van Kerkwijk Commets: 5 pages, 4 figures. Uses emulateapj5.sty, onecolfloat5.sty. Submitted to ApJL Otozhdestvlenie bylo, konechno, proizvedeno na Habblovskom teleskope. Zvezdnaya velichina ob'ekta 26.8, on ochen' goluboi i lezhit vnutri boksov oshibok HRI i Chandra. Veroyatno my vidim Relei-Dzhinsovskuyu chast' teplovogo spektra. Eti nablyudeniya podtverzhdayut, chto istochnik RX J1605.3+3249 - odinochnaya neitronnaya zvezda.
Authors: R. Dodson, D. Legge, J.E. Reynolds, P.M. McCulloch Commets: submitted to ApJ mu(alpha cos delta)=-49.60+/-0.06 m"/god, mu(delta)=+29.8+/-0.1 m"/god, parallaks p=3.4+/-0.2 m".
Authors: A.D. Erlykin, A.W. Wolfendale Commets: 11 pages, 4 figures, accepted by J.Phys.G: Nucl.Part.Phys V fizike kosmicheskih luchei odnoi iz zagadok yavlyaetsya priroda t.n. "kolena" - izloma v spektre, otkrytogo v 50-e gg. Kulikovym i Hristiansenom. Avtory dannoi stat'i v svoe vremya predlozhili interesnuyu model', gde spektral'naya detal' svyazyvaetsya s prisutstviem "edinstvennogo istochnika" - blizkogo ostatka sverhnovoi. V novoi stat'e avtory prodolzhayut razvivat' svoyu model'.
Authors: Andreas Rieschick, Gerhard Hensler Commets: 4 pages, 1 figure, to appear in Proceedings of "The Evolution of Galaxies - III. From simple approaches to self-consistent models", eds. G. Hensler et al., Kluwer Publ., Dordrecht Po rezul'tatam chislennogo modelirovaniya avtory prihodyat k sleduyushim vyvodam:
Authors: Andrew J. Bunker et al. Commets: 4 pages, 2 figures, submitted to MNRAS (Letters)
Otkryta galaktika s burnym zvezdoobrazovaniem
na ochen' bol'shom krasnom smeshenii.
Iznachal'no galaktika byla vybrana po opticheskim nablyudeniyam yuzhnogo polya
Chandry na Kosmicheskom
teleskope. Zatem na teleskope im. Keka byl poluchen ee spektr, i opredeleno
krasnoe smeshenie.
Otkrytie dalekih galaktik osobenno interesno v svyazi s nedavnimi
rezul'tatami sputnika WMAP, govoryashimi o rannei reionizacii Vselennoi.
Authors: Zoltan Haiman (Columbia University), Gilbert P. Holder (IAS) Commets: Submitted to ApJ, 10 emulateapj pages with figures included astro-ph/0302404 Istoriya Reionizacii na bol'shih krasnyh smesheniyah II: ocenki opticheskoi tolshi otnositel'no Tomsonovskogo rasseyaniya po polyarizacii relikta (The Reionization History at High Redshifts II: Estimating the Optical Depth to Thomson Scattering from CMB Polarization) Authors: Gilbert P. Holder et al. Dannye WMAP ukazyvayut na dostatochno bol'shuyu opticheskuyu tolshu po Tomsonovskomu rasseyaniyu na elektrona ionizovannogo veshestva. Pervyi pik reionizacii, po-vidimomu, prihodilsya na z~15, vtoraya reionizaciya proizoshla pri z~6 i dlitsya do sih por (t.k. okruzhayushee nas mezhgalakticheskoe veshestvo ostaetsya ionizovannym). Za podrobnostyami - v stat'i.
Authors: G.S.Bisnovatyi-Kogan Commets: 14 pages, 9 figures Journal-ref: Space Science Review, v.102, pp. 9-22 (2002) Rasskazyvaetsya o razlichnyh stohasticheskih yavleniyah v astrofizike. Opisyvaetsya 7 tipov yavlenii: dvizheniya zvezd, aktivnye yadra galaktik, oscillyacii zvezd, istochniki zhestkogo izlucheniya (rentgenovskie barstery, gamma-vspleski, stacionarnye rentgenovskie istochniki v tesnyh dvoinyh), sverhnovye (detonacionnyi front v sverhnovyh pervogo tipa), magnitnoe dinamo, dvizhenie komet v Solnechnoi sisteme. Konechno, est' i drugie yavleniya (upomyanem, naprimer, akkreciyu turbulizovannoi sredy), no nel'zya ob'yat' neob'yatnoe, i vybrannyi nabor ochen' i ochen' interesen.
Authors: Subir Sarkar (Oxford) Commets: Invited contribution to a special issue of the Proceedings of the Indian National Academy of Sciences, 20 pages, 5 figures (includes new WMAP results) Obzor posvyashen reliktovym neitrino, ih roli v obrazovanii krupnomasshtabnoi struktury, kosmologicheskie ogranicheniyam chisla tipov neitrino.
My budem starat'sya hotya by perechislit' interesnye (dlya shirokoi publiki)
stat'i, poyavivshiesya v razdele
physics
(vklyuchaya cross-listing).
Authors: John Gilman Commets: 7 pages
Ocherednaya popytka ponyat' chto zhe takoe sharovaya molniya.
Authors: Joshua Knobe, Ken D. Olum, Alexander Vilenkin Commets: 24 pages
Obsuzhdayutsya filosofskie aspekty nekotoryh sovremennyh kosmologicheskih
vozzrenii, vklyuchaya sushestvovanie vnezemnyh civilizacii i t.d.
Arhiv statei, voshedshih v predydushie vypuski.
Razdely arhiva (s iyulya 2002 g.): Poleznye astronomicheskie ssylki. Obzornye stat'i v astro-ph s 2001 g. |
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