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Soderzhanie i bystryi perehod k razdelam obzora
Dinamicheskaya evolyuciya chernyh dyr promezhutochnoi massy i ih nablyudatel'nye proyavleniya v lokal'noi chasti Vselennoi
Dinamicheskii metod opredeleniya mass zvezd s planetnymi tranzitami
Galo temnoi materii s massoi poryadka zemnoi kak pervye struktury v rannei Vselennoi
Goryachie temy nedeli
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.
Razdely arhiva (s aprelya 2003 g.): Poleznye astronomicheskie ssylki. Korotkoe esse ob elektronnyh preprintah. Obzornye stat'i v astro-ph 2001-2003 gg.
Avtory proekta
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Druzhestvennye rassylki: "Astronomiya segodnya" "Astronomiya dlya shkol'nikov" "Okno vo Vselennuyu" Spisok astrorassylok |
Obzory preprintov astro-ph
Vypusk N97
astro-ph za 17 - 31 yanvarya 2005 goda: izbrannye stat'i
Goryachie temy nedeli
Ul'tramoshnye istochniki
Na lovca i zver' bezhit. V blizhaishem nomere Zvezdocheta dolzhna poyavit'sya stat'ya odnogo iz avtorov obzorov, posvyashennaya ul'tramoshnym istochnikam, a vtoraya polovina yanvarya okazalas' chrezvychaino bogatoi na rezul'taty po etomu tipu ob'ektov. V osnovnom stat'i predstavleny odnoi gruppoi issledovatelei, poetomu my srazu zhe obratim vnimanie na ih ogromnuyu (130 stranic) stat'yu Ultra-luminous X-ray Sources in nearby galaxies from ROSAT HRI observations I. data analysis. Zamet'te, chto u stat'i stoit nomer I. Eto oznachaet, chto ona soprovozhdaetsya ryadom drugih, i ih vy takzhe mozhete naiti v tekushem vypuske obzorov. Otmetim zdes' zhe stat'yu Dynamical evolution of intermediate mass black holes and their observable signatures in the nearby Universe. V nei rech' idet o chernyh dyrah promezhutochnyh mass, kotorye mogut byt' akkreciruyushimi ob'ektami v ul'tramoshnyh istochnikah. Rassmotreny chernye dyry, vedushie svoyu rodoslovnuyu ot samyh pervyh zvezd vo Vselennoi.
Referaty otdel'nyh statei
Authors: M. G. Hidas et al. Comments: 15 pages, 8 figures, submitted to MNRAS Zadumyvalis' li vy nad tem, chto v Rossii po suti net ni odnoi nauchnoi gruppy, da dazhe ni odnogo uchenogo, aktivno zanimayushegosya ekzoplanetami. Ni v teorii, ni v nablyudeniyah. Vidimo, prichina v tom, chto eto novaya oblast', a u nas i tak inerciya velika, da eshe "slozhnye ekonomicheskie usloviya". A mezhdu tem, v mire raboty vedutsya dazhe na nebol'shih teleskopah. V etoi stat'e rasskazyvaetsya o proekte, osushestvlyaemom na polumetrovom teleskope Novogo Yuzhnogo Uelsa (Avstraliya). Poka planet ne obnaruzheno (detal'nye nablyudeniya chetyreh vyyavlennyh kandidatov pokazali, chto oni yavlyayutsya zatmennymi dvoinymi), no rabota idet, metodika sovershenstvuetsya. Budem zhdat'!
Authors: H. Baumgardt, E. K. Grebel, P. Kroupa Comments: 5 pages, 1 figure, accepted for publication in MNRAS Authors: J. I. Read, Ben Moore Comments: 5 pages, 2 figures. Submitted to MNRAS Srazu dve stat'i po MOND ot dvuh raznyh grupp avtorov. Nachnem so vtoroi. V nei avtory pokazyvayut, chto ispol'zovanie dannyh po prilivnym potokam (voznikayushim pri razrushenii nebol'shoi galaktiki) v Mlechnom Puti ne yavlyaetsya perspektivnym s tochki zreniya proverki teorii MOND. Otlichiya ot N'yutonovskogo potenciala okazyvayutsya neveliki. Zato avtory pervoi stat'i predlagayut novyi tip ob'ektov, kotoryi mozhno ispol'zovat' dlya testov teorii gravitacii. Eto - sharovye skopleniya. Izmereniya dispersii skorostei v skopleniyah mogut sushestvenno ogranichit' fantazii teoretikov.
Authors: Sandip K. Chakrabarti Comments: 13 pages, 8 figures, Astronomy and Space Science (in press), Proceedings of the Hong Kong Conference (2004) Edited by Cheng and Romero Authors: Sandip K. Chakrabarti Comments: 12 pages, 10 figures To be published in the Proceedings of 5th Microquasar Conference (Beijing, 2004) Trudno oboiti vnimaniem tot fakt, chto 17 yanvarya (t.e. za odin den'!) poyavilos' 22 (!) stat'i, odnim iz avtorov kotoryh yavlyaetsya Sandip K. Chakrabarti. Obratim vnimanie chitatelei na dve iz nih. Eto obzory, posvyashennye chernym dyram.
Authors: Ji-Feng Liu et al. Comments: 2004ApJ...602..249L Authors: Ji-Feng Liu et al. Comments: 29 pages, 10 figures Authors: Ji-Feng Liu et al. Comments: 12 pages, 3 figures. accepted for publication in ApJ Letter Authors: Ji-Feng Liu et al. Comments: 130 preprint pages, 76 pfigures, 3 tables, 67 pages in ApJS. to appear in the March issue in ApJS Authors: Ji-Feng Liu et al. Comments: 45 pages, 14 figures, 5 tables. submitted to ApJ
Predstavlyaem stat'i, sostavivshie osnovu "goryachei temy" vypuska. Kak my neodnokratno otmechali, sverhmoshnye istochniki - odna iz naibolee interesnyh zagadok v astrofizike vysokih energii. I imenno nablyudeniya (v pervuyu ochered' nablyudeniya normal'nyh zvezd-komponentov) dadut otvet kakie zhe chernye dyry sidyat v etih sistemah. V pervoi iz rech' idet kak raz ob obnaruzhenii opticheskogo kompan'ona odnogo iz UMI (ul'tramoshnyh istochnikov). Obrabotka dannyh i ih analiz pokazyvayut, chto naibolee veroyatno, chto normal'naya zvezda yavlyaetsya sverhgigantom klassa B0. Dlya opredeleniya massy chernoi dyry ponadobyatsya novye nablyudeniya (v chastnosti, avtory nadeyutsya obnaruzhit' orbital'nyi period). Opticheskie nablyudeniya UMI summirovany vo vtoroi stat'e. Vo tret'ei stat'e rasskazyvaetsya ob obnaruzhenii kvaziperiodicheskih izmenenii rentgenovskoi svetimosti istochnika v spiral'noi galaktike NGC 628. Period sostavlyaet poryadka 1-2 chasov. Eto unikal'noe povedenie dlya UMI. Sravnenie s povedeniem drugih tipov istochnikov s chernymi dyrami pozvolyaet zapodozrit', chto massa chernoi dyry v issleduemom ob'ekte sostavlyaet neskol'ko tysyach mass Solnca. T.e. eto, po vsei vidimosti, chernaya dyra promezhutochnoi massy. Dve poslednie raboty predstavlyayut rezul'tat obrabotki dannyh po UMI v blizkih galaktikah, poluchennyh eshe na sputnike ROSAT.
Authors: R. M. Bandyopadhyay et al. Comments: 6 pages, In Proc. of `Interacting Binaries: Accretion, Evolution, and Outcomes'', eds. L. A. Antonelli et al., AIP, Cefalu, Sicily, 2004 Nablyudeniya na sputnike Chandra pokazali okolo 800 rentgenovskih istochnikov v oblasti s ploshad'yu primerno poltora kvadratnyh gradusa vokrug galakticheskogo centra. Bol'shinstvo iz nih imeyut nebol'shuyu rentgenovskuyu svetimost' poryadka 1032-1033 erg/s. Avtory obsuzhdayut vozmozhnuyu prirodu etih ob'ektov, a takzhe predstavlyayut pervye rezul'taty infrakrasnyh nablyudenii etoi oblasti. Oni polagayut, chto bOl'shaya chast' istochnikov - eto rentgenovskie dvoinye s kompaktnymi ob'ektami. Vozmozhno, chto sredi etih istochnikov est' novye tipy tesnyh dvoinyh sistem.
Authors: Marta Volonteri, Rosalba Perna Comments: 11 pages, Accepted for publication in MNRAS My podrobno pisali o tom, chto v ramkah sovremennyh scenariev (vklyuchayushih, v chastnosti, fenomen t.n. "gravitacionno-volnovoi rakety") vo Vselennoi dolzhno byt' dostatochno mnogo chernyh dyr promezhutochnyh mass, letayushih kak v mezhgalakticheskom prostranstve, tak i v galo galaktik. Letom 2004 goda poyavilas' stat'ya (astro-ph/0407285), gde rassmatrivalas' vozmozhnost' ob'yasneniya UMI (ul'tramoshnyh rentgenovskih istochnikov) takimi "bluzhdayushimi" chernymi dyrami, akkreciruyushimi veshestvo mezhzvezdnoi sredy. Marta Volonteri i Rozal'ba Perna v svoei rabote obsuzhdayut takuyu vozmozhnost' v neskol'ko bol'shih detalyah. Eto stalo vozmozhnym blagodarya tomu, chto Marta s soavtorami sozdali moshnuyu komp'yuternuyu programmy, otslezhivayushuyu evolyuciya chernyh dyr v scenarii ierarhicheskogo skuchivaniya, nachinaya s "zarodyshevyh" chernyh dyr, voznikayushih iz samyh pervyh zvezd. Vyvody, na nash vzglyad, neodnoznachnye. S odnoi storony (kak mozhno bylo ozhidat') kolichestvo dostatochno yarkih istochnikov nedostatochno veliko, chtoby vnesti sushestvennyi vklad v populyaciyu UMI. S drugoi, est' nekotorye lazeiki, pozvolyayushie prodolzhit' obsuzhdenie scenariya (otmetim otdel'no, chto Krolik v svoei stat'e astro-ph/0407285 obsuzhdal i dovol'no ekzoticheskii variant obrazovaniya massivnyh zvezd, podobnyh Pop III, pryamo v diskah sovremennyh galaktik za schet akkrecii pervichnogo gaza s maloi metallichnost'yu; takaya vozmozhnost' takzhe poka ne zakryta.).
Authors: Bryan M. Gaensler Comments: 12 pages, 2 embedded EPS figures, 1 GIF figure. Advances in Space Research, in press V poslednie gody poyavlyaetsya vse bol'she danynh ob udarnyh volnah, voznikayushih vokrug neitronnyh zvezd. Dostatochno chasto poyavlenie volny svyazano s dvizheniem neitronnoi zvezdy v mezhzyvezdnoi srede. Okazyvaetsya, chto izuchenie takih golovnyh udarnyh voln mozhet rasskazat' mnogo novogo o samih neitronnyh zvezdah.
Authors: Schuyler D. Van Dyk Comments: 6 pages, 4 figures, to appear in "1604-2004: Supernovae as Cosmological Lighthouses," eds. M. Turatto, W. Shea, S. Benetti and L. Zampieri, ASP Conference Series Dlya ponimaniya mehanizma sverhnovoi ochen' vazhno znat' kakie zvezdy vzryvayutsya. Zadacha eta neprostaya, t.k. v osnovnom sverhnovye otkryvayutsya v dostatochno dalekih galaktikah, i tochnoe vydelenie na arhivnyh snimkah vzorvavsheisya zvezdy predstavlyaet soboi slozhnuyu problemu. Odnako v nekotoryh sluchayah vse-taki udalos' s bol'shoi dostovernost'yu vychlenit' izobrazhenie predsverhnovoi. Vse sovremennye rezul'taty v etoi oblasti summirovany v kratkom obzore Van Daika.
Authors: G. Bono et al. Comments: 6 pages Omega Centavra - samoe massivnoe sharovoe skoplenie v Galaktike. Ego aktivno nablyudayut v samyh raznyh diapazonah i s razlichnymi celyami. Avtory predstavlyayut pervye rezul'taty obrabotki dannyh, poluchennyh na Kosmicheskom teleskope. V fotometricheskii katalog vneseno bolee milliona zvezd. Pervaya zadacha, na kotoroi koncentriruyutsya avtory - obnaruzhenie belyh karlikov. Podcherknem, predstavleny predvaritel'nye rezul'taty, odnako uzhe rech' idet ob obnaruzhenii 600 istochnikov etogo tipa.
Authors: Thibault Damour Comments: 35 pages, 3 figures, invited talk given at the Solvay Symposium on Henri Poincare (ULB, Brussels, 8-9 October 2004) Tibo Damur - izvestneishii specialist v oblasti teorii otnositel'nosti, matematicheskoi fiziki i t.d. Dannaya stat'ya - eto bol'shoi obzor, posvyashennyi Puankare. Tochnee, posvyashennyi ego rabotam. T.e. krome istoricheskoi chasti est' eshe i matematicheskaya.
Authors: Miguel A. de Avillez^(1,2) and Dieter Breitschwerdt Comments: 3 Pages, 3 figures (including 1 jpg image and 3 plots); poster paper to appear in "Astrophysics in the Far Ultraviolet: Five Years of Discovery with FUSE", 2005, ASP Conference Series, eds. G. Sonneborn, H. W. Moos, and B-G Andersson Kratko opisyvaetsya ocherednaya popytka chislenno promodelirovat' obrazovanie Mestnogo puzyrya. Rezul'taty pokazyvayut, chto poslednii vzryv proizoshel 0.4-1.1 milliona let nazad, a naibolee blizkii k Solncu imel mesto 2.1-3.5 milliona let nazad.
Takzhe sm. stat'yu teh zhe avtorov
astro-ph/0501586
Avtoram stat'i udalos' obnaruzhit' interesnyi vid peremennosti aktivnyh yader galaktik. Eto bystrye (masshtab poryadka odnogo mesyaca dlya AYaG schitaetsya bystrym) vspyshki, obnaruzhennye v opticheskom diapazone ot shesti ob'ektov. Dlya vyyavleniya vspyshek prishlos' provesti tshatel'nyi analiz, t.k. polnaya svetimost' galaktiki izmenyaetsya za schet nih lish' na neskol'ko procentov. Avtory svyazyvayut proishozhdenie vspyshek s processami neposredstvenno vblizi sverhmassivnyh chernyh dyr. Takzhe oni ukazyvayut na analogiyu nablyudayushegosya fenomena s infrakrasnymi vspyshkami, obnaruzhennymi ot centra nashei Galaktiki.
Authors: A. Melchiorri et al. Comments: 5 Pages. To appear in the Proceedings of NOW2004, Conca Specchiulla, Otranto Italy, September 2004 Ispol'zuya dannye po mikrovolnovomu fonu i krupnomasshtabnoi strukture, avtory poluchayut ogranicheniya na summu mass neitrino. Eti rezul'taty obsuzhdayutsya v kontekste razlichnyh nazemnyh eksperimentov (naprimer, po neitrinnym oscillyaciyam).
Authors: Hidekazu Hanayama et al. Comments: 10 pages, 2 figures V astrofizike dostatochno yasna situaciya s tem, kak mozhno putem usileniya nekotorogo zatravochnogo polya ob'yasnit' nablyudaemuyu kartinu magnitnyh polei v galaktikah. Odnako mehanizm, porozhdayushii zatravochnoe pole ostaetsya neizvestnym. Putem chislennogo modelirovaniya avtory pokazyvayut, chto pole dostatochnoi velichiny mozhet byt' polucheno v ostatkah pervyh sverhnovyh. Generaciya polya proishodit v sloe na granice rasshiryayushegosya puzyrya i mezhzvezdnoi sredy.
Authors: James M. Stone, Thomas A. Gardiner Comments: 11 pages, style files included, Conference Proceedings: "Magnetic Fields in the Universe: from Laboratory and Stars to Primordial Structures", More information on Athena can be found at http://www.astro.princeton.edu/~jstone/athena.html Authors: Thomas A. Gardiner, James M. Stone Comments: 45 pages, 13 figures, accepted for publication in J. Comp. Phys. Dve stat'i, v kotoryh opisyvaetsya chislennaya shema i kod dlya modelirovaniya magnito-gidrodinamicheskih processov. Krome opisaniya predstavleny rezul'taty testov programmy. Veroyatno, etot kod pridet na smenu znamenitomu ZEUS.
Authors: Abraham Loeb Comments: 4 pages, 2 figures, submitted to ApJL Predlagaetsya metod, v kotorom za schet prohozhdeniya planety po disku zvezdy budet vozmozhno opredelit' zvezdnuyu massu. Ocenki pokazyvayut, chto budushie missii tipa Kepler i COROT smogut dostich' chuvstvitel'nosti, dostatochnoi dlya obnaruzheniya effekta. Effekt zaklyuchaetsya v iskazhenii simmetrichnoi krivoi bleska vo vremya prohozhdeniya za schet uskoreniya planety. Kstati, podrobno o planetnyh tranzitah (prohozhdeniyah po disku zvezdy) mozhno prochest' v dissertacii astro-ph/0501558.
Authors: Sangwook Park et al. Comments: 9 pages, AdSpR in press Sputnik Chandra vedet monitoring ostatka sverhnovoi 1987A. Za neskol'ko let nablyudenii udalos' zaregistrirovat' interesneishie yavleniya, soprovozhdayushie evolyuciyu ostatka, naprimer, poyavlenie yarkih obrazovanii vo vnutrennem kol'ce. Podrobnee - v stat'e.
Authors: Josep M. Paredes Comments: Universitat de Barcelona, Departament d'Astronomia i Meteorologia, 12 pages, 5 figures. Invited talk presented at the International Symposium "High-Energy Gamma-Ray Astronomy", 26-30 July 2004, Heidelberg (Germany). To be published by AIP Proceedings Series Obzor posvyashen mikrokvazaram - tesnym dvoinym sistemam s relyativistskimi dzhetami. Avtor koncentriruet vnimanie na processah, privodyashih v izlucheniyu fotonov vysokoi energii, t.e. gamma-kvantov.
Authors: R. Aloisio et al. Comments: 12 pages, no figures, talk presented at the Vulcano Workshop 2004 My mnogo pisali o tom, chto pri svoem rasprostranenii na mezhgalakticheskie rasstoyaniya chasticy vysokih energii mogut podvergat'sya deistviyu effektov, svyazannyh s kvantovoi gravitaciei. Razlichnye avtory s pomosh'yu razlichnyh metodik pytalis' i pytayutsya poluchat' ogranicheniya na parametry sozdavaemyh teorii kvantovoi gravitacii, ispol'zuya dannye po kosmicheskim lucham i po dannym nablyudenii vnegalakticheskih ob'ektov. V etoi stat'e daetsya nekotoryi obzor dannoi oblasti, kotoruyu avtory nazyvayut "fenomenologicheskoi kvantovoi gravitaciei".
Authors: Juerg Diemand, Ben Moore, Joachim Stadel Comments: 11 pages, 3 figures, published in Nature, January 27, 2005; Nature 433 (2005) 389 - 391 Potryasayushe interesnyi rezul'tat poluchen v rezul'tate chislennogo modelirovaniya! Gruppa shveicarskih astrofizikov schitaet, chto pervye struktury vo Vselennoi imeli massu poryadka massy Zemli (razmer byl pri etom poryadka razmera Solnechnoi sistemy). Oni pokazyvayut, chto pri realistichnyh predpolozheniyah do 1015 takih obrazovanii iz temnoi materii (iz neitralino, v dannom sluchae) dolzhny byli sohranit'sya v galo Galaktiki. Raz v neskol'ko tysyach let takoe galo dolzhno prohodit' cherez Solnechnuyu sistemu.
Authors: L. Perivolaropoulos Comments: Invited Review at the DPU Workshop: The Density Fluctuations in the Universe: Beyond the Inflaton Paradigm (Athens, June 2004) (see http://www.physics.ntua.gr/dpu/). 13 two column pages, 5 figures Avtor polagaet, chto teoriya kosmicheskih strun v primenenii k kosmologicheskim vozmusheniyam plotnosti yavlyaetsya prekrasnym primerom zdorovogo progressa v nauke. Za otnositel'no korotkii srok byla vydvinuta horosho motivirovannaya gipoteza. Zatem gipoteza byla razrabotana do urovnya polnocennoi teorii s chetkimi predskazaniyami. Predskazaniya byli provereny i otbrosheny. T.o. za neskol'ko desyatiletii teoriya proshla ves' put' "po Popperu" ot idei do musornoi korziny. Ogovorimsya. Musornye korziny byvayut raznye. V dannom sluchae teoriya sygrala bol'shuyu rol' v razvitii kosmologii (da i ne tol'ko kosmologii), poetomu razumeetsya, ne stoit prinizhat' ee znachenie!
Authors: Noam Soker Comments: Submitted to MNRAS Posle poyavleniya raboty nemeckih uchenyh, v kotoroi oni izmerili magnitnye polya central'nyh zvezd planetarnyh tumannostei (my pisali ob etom v proshlom vypuske) neizbezhno dolzhna byla nachat'sya diskussiya. Vot prevaya stat'ya. Avtor pytaetsya pokazat', chto magnitnye polya ne mogut otvechat' za bipolyarnuyu formu planetarnyh tumannostei. On polagaet, chto energii i uglovogo momenta budet nedostatochno dlya dostizheniya nablyudaemogo effekta. V kachestve al'ternativy rassmatrivaetsya dvoistvennost' sistemy (t.e. sfericheskaya simmetriya narushaetsya za schet prisutstviya vtoroi zvezdy). Sm. takzhe vtoruyu rabotu, gde rassuzhdeniya o dvoistvennosti sverhmassivnyh chernyh dyr prilagayutsya k formirovaniyu gigantskih polostei v skopleniyah galaktik.
Authors: Katherine Freese Comments: 7 pages, 1 figure, in press, New Astronomy Reviews
Korotkii obzor, posvyashennyi odnoi iz al'ternaivnyh teorii v sovremennoi
kosmologii.
Osnovnaya sut' modeli sostoit v nebol'shoi modifikacii uravnenii Fridmana.
Poluchayushayasya ploskaya Vselennaya rasshiryaetsya s uskoreniem bezo vsyakogo vklada
"vakuumnogo chlena". Mozhno obsuzhdat' razlichnye interpretacii predlozhennoi
teorii. Naprimer, model' mozhet rabotat' v "mire bran", t.e. v ramkah
populyarnoi seichas teorii o
"zhizni na brane".
My budem starat'sya hotya by perechislit' interesnye (dlya shirokoi publiki) stat'i, poyavivshiesya v razdele physics (vklyuchaya cross-listing).
Authors: R.G. Harrison, K.L. Aplin Comments: In: Chauzy S. and Laroche P. (ed.), Proceedings of 12th International Conference on Atmospheric Electricity, Versailles, Paris 9th-13th June 2003 (ISBN 2-7257-0009-4), 2, 789-792 V 19 veke vo mnogih evropeiskih gorodah provdilis' vysokotochnye nablyudeniya gradienta elektricheskogo potenciala v atmosfere. Provodilis' oni i v Parizhe na tol'ko chto postroennoi Eifelevoi bashne. Rezul'taty izmerenii sil'no zavisyat ot zagryaznennosti vozduha. T.o. teper' my imeem prekrasnye dannye o tom, chem dyshali evropeicy bolee veka nazad.
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