Novosti nauki |
The R.A.P. Project |
17.10.02. astro-ph za 14 - 17 oktyabrya 2002 goda: izbrannye stat'i |
Daetsya obzor po akkrecii na chernye dyry. V korotkoi zametke prakticheski bez formul dayutsya vse osnovnye idei. Odnako, po toi zhe prichine dlya specialistov stat'ya malo interesna. Ochen' polezna dlya studentov-aspirantov, i, kak govoritsya, dlya "specialisto smezhnyh special'nostei".
Authors: Piero Madau Comments: 11 pages. Invited talk at the ESO-CERN-ESA Symposium on Astronomy, Cosmology, and Fundamental Physics, March 4-7 2002, Garching, Germany Daetsya obzor po reionizacii (vtorichnoi ionizacii) Vselennoi. Sut' etogo yavleniya primerno takova: posle togo kak na krasnom smeshenii z=10 obrazuyutsya pervye zvezdy, kvazary i t.d. eti istochniki svoim moshnym ul'trafioletovym izlucheniem ionizuyut znachitel'nuyu dolyu mezhgalakticheskogo gaza (a napomnim, chto otnositel'no nezadolgo do etogo kak raz proshla epoha rekombinacii). Nalichie vtorichnoi ionizacii sushestvennym obrazom skazyvaetsya na dal'neishei evolyucii Vselennoi.
Authors: Qingjuan Yu Comments: 27 pages, including 10 figures, MNRAS in press Chem pitayutsya kvazary? Esli v ih nedrah nahodyatsya sverhmassivnye chernye dyry (a my bol'she chem na 99 procentov uvereny, chto eto tak), to nuzhen gaz, chtoby bylo chto akkrecirovat'. Est' raznye vozmozhnye istochniki takogo gaza. Odin iz nih - stolknoveniya zvezd i prilivnye razryvy zvezd. Dolgoe vremya schitalos', chto eti mehanizmy odni iz luchshih. Osobenno izyashnaya ideya byla svyazana s tem, chto ochen' massivnye chernye dyry uzhe ne mogut razorvat' zvezdu, a potomu na bol'shih krasnyh smesheniyah kvazarov mnogo, a okolo nas ih malo. Odnako, Magorrian & Tremaine (1999) pokazali, chto dlya yarkih galaktik razryvy zvezd ne mogut davat' opredelyayushego vklada. V etoi zhe stat'e avtory pokazyvayut, chto i stolknoveniya zvezd ne mogut byt' osnovnym istochnikom gaza. Znachit, neobhodimy drugie rezervuary. Gaz mozhet postupat' ili v rezul'tate sliyaniya galaktik, ili zhe ego mogut vybrasyvat' zvezdy v processe ih evolyucii v techenie prevogo milliarda let zhizni galaktiki.
Authors: Massimo Della Valle Comments: Invited Review (14 pag.). To appear in the Proceedings of the Conference `Classical Nova Explosions'', M. Hernanz and J. Jose eds., American Inst. of Physics, 2002 Novye zvezdy - eto tesnye dvoinye sistemy s belymi karlikami. Karlik akkreciruet veshestvo zvezdy-sosedki, a zatem proishodit termoyadernyi vzryv. Posle process povtoryaetsya. Seichas o novyh zvezdah izvestno uzhe ochen' mnogo. V stat'e avtor daet obzor sovremennogo sostoyaniya del. V chastnosti, opisyvayutsya dva tipa novyh: yarkie bystrye i slabye medlennye. Pervye iz nih svyazany s massivnymi belymi karlikami v tonkom diske galaktiki i spiral'nyh rukavah (tam raspolozheny bolee massivnye zvezdy). Vtorye - s tostym diskom i baldzhem.
Authors: Ehud Behar, Steven M. Kahn Comments: Review for proccedings of NASA Laboratory Astrophysics Workshop, May 1-3 2002, Farid Salama, Editor Dlya razvitiya rentgenovskoi spektroskopii v astronomii (chto vazhno v svyazi s zapuskami takih sputnikov kak N'yuton i Chandra) neobhodimy i laboratornye issledovaniya. V stat'e opisyvayutsya eksperimenty Lourensovskoi Nacional'noi Laboratorii v Livermore. Osnovnye rezul'taty svyazany s issledovaniyami ionizirovannogo zheleza.
Authors: Chris Pearson et al. Comments: 18 pages, 10 figures, submitted to MNRAS, models can be accessed from http://astro.ic.ac.uk/~cpp/astrof Do sih por astronomy ispol'zuyut katalogi, sostavlennye na infrakrasnom sputnike IRAS. ASTRO-F - eto superIRAS. V stat'e opisyvaetsya etot yaponskii proekt. Otdel'no obsuzhdaetsya kak dannye ASTRO-F budut dopolnyat' rezul'taty novoi amerikanskoi IK-missii SIRTF.
Authors: Heinrich J. V\"olk Comments: 3 pages, 11 figures. To appear in "Astronomy, Cosmology and Fundamental Physics", ed. P. A. Shaver, L. Di Lella, and A. Gimenez, Proc. ESA-CERN-ESO Symposium, Garching, March 2002. Springer-Verlag, Berlin, Heidelberg, series "ESO Astrophysics Symposia" Opisyvayutsya poslednie rezul'taty i blizhaishie perspektivy v gamma-astronomii vysokih energii.
Authors: A.Ivanchik et al. Comments: 6 pages, 1 figure. Talk presented at the JENAM 2002 Workshop on Varying Fundamental Constants, Porto, 4th September 2002. To be published in the Conference Proceedings Napomnim o tom, chto v poslednee vremya diskussiya o variacii fundamental'nyh konstant pereshla v novoe ruslo: "a chto sobstvenno menyaetsya?" Skorost' sveta, massy ili zhe vse-taki ih kombinaciya (t.e. bezrazmernaya velichina). Napomnim takzhe o tom, chto odna iz vedushih grupp po eksperimental'nomu izucheniyu variacii konstant rabotaet v FTI im. Ioffe. V stat'e rossiiskie uchenye v soavtorstve s francuzskimi astronomami opisyvayut issledovaniya spektrov kvazarov, pozvolyayushie nalozhit' samyi zhestkii na segodnyashnii den' predel na izmeneniya otnosheniya massy protona k masse elektrona. Samoi variacii otnosheniya net (ili skazhem tak, net signala o variacii na urovne treh standartnyh otklonenii).
Authors: C. Vignali et al. Comments: 1 page, 2 figures, anabs.cls style file. Proceedings for the "X-ray Surveys: in the light of new observatories" Workshop (submitted to Astron. Nachrichten) Poyavilos' srazu tri stat'i podryad, posvyashennye nablyudeniyam istochnikov na bol'shih krasnyh smesheniyah s pomosh'yu sputnika Chandra: astro-ph/0210308, astro-ph/0210309, astro-ph/0210310. Krome etogo eshe odna stat'ya posvyashena opticheskim nablyudeniyam istochnikov na z=3: astro-ph/0210314. Dlya izucheniya vnegalakticheskih ob'ektov na Chandre otvedeno dovol'no mnogo vremeni. Sdelano neskol'ko glubokih "prokolov" s ekspoziciyami po 2 mln. sekund. V spektrah nekotoryh istochnikov udaetsya naiti detali, naprimer emissionnye linii zheleza. Kolichestvo dannyh budet rasti, krome togo, s uzhe sdelannyh nablyudenii tol'ko-tol'ko snimayut slivki....
Authors: James Liebert et al. Comments: 16 pages, 2 figures, Astronomical Journal in press -- Jan 2003 issue Astronomy ishut tam, gde svetlee. Nazyvaetsya eto "effekt selekcii". Primerov ochen' mnogo. Skazhem, otkrytie radiopul'sarov (esli pole neitronnyh zvezd bylo men'she, to pul'sary byli by slabee, ili zhe voobshe ne poyavlyalis'; esli zhe pole bylo by sushestvenno bol'she, to pul'sary bystro umirali by, ili tozhe ne poyavlyalis', no uzhe iz-za effekta raspada fotona v pole na dva drugih fotona). V stat'e obsuzhdayutsya dannye po izmereniyam magnitnyh polei belyh karlikov, i tut tozhe est' effekty selekcii. Grubo govorya, chem yarche istochnik i chem sil'nee pole, tem legche ego izmerit'. Maksimal'nye polya na etih ob'ektah dohodyat do 109 Gs! Vpervye polya u belyh karlikov byli obnaruzheny v 1970 g. Seichas izvestno okolo 100 belyh karlikov s izmerennym polem. S techeniem vremeni predel na izmeryaemoe pole umen'shaetsya. U nas v strane izmeryat' nebol'shie polya na belyh karlikah umeyut v SAO (S. Fabrika, G. Valyavin i dr.). No do sih por neizvestna funkciya raspredeleniya belyh karlikov po magnitnym polyam. Avtory obsuzhdayut selekcionnye effekty, kotorye mogut privodit' k iskazheniyu raspredeleniya belyh karlikov po magnitnym polyam. Po ih mneniyu okolo 10 procentov etih ob'ektov mogut imet' sushestvennoe magnitnoe pole.
Authors: Schuyler D. Van Dyk et al. Comments: 19 pages, 23 figures, to appear in PASP (2003 Jan) Odna iz problem v astrofizike sverhnovyh zvezd - ponyat' kakie zvezdy kakie sverhnovye porozhdayut. Dlya etogo hotelos' by imet' izobrazhenie zvezdy do vzryva. Avtory predstavlyayut rezul'taty poiskov takih dannyh. Arhivy Kosmicheskogo teleskopa i drugih proektov pozvolili obnaruzhit' praroditelei neskol'kih sverhnovyh raznyh tipov (konechno, rech' ne idet o sverhnovyh tipa Ia). Est' ukazaniya na obnaruzhenie shesti zvezd, kotorye zatem vzorvalis'. SN II porozhdayutsya krasnymi sverhgigantami. S SNe Ib/c ne vse tak yasno (sm. takzhe nizhe pro sliyaniya massivnyh zvezd).
Authors: J. Garriga, A. Vilenkin Comments: 21 pages, 3 figures Antropnyi princip yavlyaetsya ochen' populyarnym podhodom v popytkah dat' otvety na "proklyatye" voprosy kosmologii. V svoei stat'e Garriga i Vilenkin pytayutsya ne tol'ko chto-to ob'yasnyat', no i predskazyvat': vklad kosmologicheskogo chlena, budushee "shlopyvanie" Vselennoi... Chast' iz ih predskazanii mozhno proverit', chast' (po ih zhe sobstvennomu mneniyu) - net.
Authors: Natalia Ivanova, Philipp Podsiadlowski Comments: 4 pages, 1 figure, proc. ESO/MPA/MPE Workshop "From Twilight to Highlight: The Physics of Supernovae" Avtory rassmatrivayut sliyanie massivnyh zvezd na stadii obshei obolochki i dal'neishuyu evolyuciyu obrazovavsheisya "dvazhdy massivnoi" zvezdy vplot' do vzryva sverhnovoi. Okazyvayutsya vozmozhnymi tri varianta sliyaniya, privodyashie k obrazovaniyu krasnogo sverhgiganta, golubogo sverhgiganta (vozmozhno imenno takova zvezda, vzorvavshayasya kak SN1987A) i krasnogo giganta.
Authors: M. C. Smith, S. Mao, B. Paczynski Comments: 24 pages, 5 figures (in colour). Accepted for publication in MNRAS Prodolzhaetsya perehod ot prosteishih modelei mikrolinzirovaniya ko vse bolee i bolee prodvinutym. V dannoi stat'e obsuzhdaetsya vozmozhnost' nalichiya uskoreniya v otnositel'nom dvizhenii istochnika, linzy i nablyudatelya. Vazhno, chto raznye tonkie effekty mogut imitirovat' drug druga. Chast' stat'i posvyashena imenno etoi probleme.
Authors: Joseph Silk Comments: To appear in the procedings of: The Evolution of Galaxies. III: From simple approaches to self-consistent models (Kiel, Gemany, July 2002) Obzor po obrazovaniyu diskovyh galaktik. Kazalos' by, chto mozhet byt' proshe chem diskovaya galaktika. An net. Tut eshe mnogo belyh pyaten (pol'zuyas' sluchaem, rekomenduyu stat'yu I.I. Pashi v Istoriko-Astronomicheskih issledovaniyah za 2002 g. o stanovlenii teorii obrazovaniya spiral'noi struktury, nadeyus', chto ona poyavitsya v HTML vide na Astronete).
Authors: Eline Tolstoy Comments: 10 pages, 4 figures, Invited talk in "Galaxy Evolution III: From Simple Approaches to Self-Consistent Models" (Kiel, Germany, July 16-20, 2002) eds. G. Hensler et al., in press Malen'kie galaktiki ne menee vazhny chem bol'shie, a po mneniyu nekotoryh specialistov oni dazhe bolee vazhny dlya ponimaniya evolyucii vnegalakticheskih ob'ektov. Obzor posvyashen imenno etomu: roli karlikovyh galaktik v nashem ponimanii evolyucii galaktik vcelom.
Arhiv statei, voshedshih v predydushie vypuski.
Razdely arhiva (s iyulya 2002 g.): Poleznye astronomicheskie ssylki. Obzornye stat'i v astro-ph s 2001 g. |
|
Publikacii s klyuchevymi slovami:
elektronnye preprinty - obzory - astro-ph
Publikacii so slovami: elektronnye preprinty - obzory - astro-ph | |
Sm. takzhe:
Vse publikacii na tu zhe temu >> |