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The R.A.P. Project (Reviews of Astro-Ph) 2003

Chernye dyry
(Arhiv Chernye dyry:
v.2, 2004, v.1, 2002-2003)

Vypusk 63. 16-31 dekabrya 2003

miniobzor astro-ph/0312470 Budushee rentgenovskoi spektroskopii galakticheskih dvoinyh chernyh dyr (The Future of X-ray Spectroscopy of Galactic Black Hole Binaries)
Authors: Michael A. Nowak
Comments: 8 pages, 7 figures

V etom malen'kom obzore perepleteny dve temy: 1) chto mogut uvidet' uzhe deistvuyushie i gotovyashiesya k zapusku rentgenovskie observatorii, 2) kakie effekty mozhno obnaruzhit' v rentgenovskih zvezdnyh istochnikah s chernymi dyrami.


Vypusk 62. 01-15 dekabrya 2003

astro-ph/0312033 Ukazaniya na vrashenie chernoi dyry v GX339-4: XMM-N'yuton i RXTE spektroskopiya v samom vysokom sostoyanii (Evidence for Black Hole Spin in GX 339-4: XMM-Newton EPIC-pn and RXTE Spectroscopy of the Very High State)
Authors: J.M.Miller et al.
Comments: 5 pages, 2 figures, submitted to ApJ Letters

V dannoi rabote proveden analiz asimmetrichnogo profilya rentgenovskoi K-al'fa linii zheleza po dannym XMM-N'yuton (76000 c) i RXTE (9000 s) v samyh vysokih sostoyaniyah za 2002-2003 gody. Eta liniya obrazuetsya vo vnutrennih chastyah akkrecionnogo diska. Nailuchshaya samosoglasovannaya model' sootvetstvuet vrashayusheisya chernoi dyre s a>0.8-0.9. (a - bezrazmernyi uglovoi moment chernoi dyry: a=cJ/GM2.)


Vypusk 61. 16-30 noyabrya 2003

astro-ph/0311500 Magnitnye akkrecionnye potoki v Kerrovskoi metrike (Magnetically Driven Accretion Flows in the Kerr Metric II: Structure of the Magnetic Field)
Authors: Shigenobu Hirose et al.
Comments: 10 pages + 14 figures, submitted to ApJ.

Avtory rasschitali kak zakruchivayutsya magnitnye polya, vmorozhennoe v padayushee na vrashayushuyusya chernuyu dyru veshestvo.

Variant stat'i s kartinkami vysokogo razresheniya mozhno posmotret' na saite avtorov.


astro-ph/0311512 Pryamaya podpitka central'noi chernoi dyry Galaktiki zvezdnymi vetrami blizhaishih zvezd (Direct Feeding of the Black Hole at the Galactic Center with Radial Gas Streams from Close-In Stellar Winds)
Authors: Abraham Loeb (Harvard Univ.)
Comments: 4 pages, 2 figures, ApJL, submitted

Avtor pokazal, chto dlya ob'yasneniya ochen' nizkoi nablyudaemoi svetimosti central'noi chernoi dyry nashei Galaktiki (ob'ekta Sgr A*) dostatochno chasti zvezdnogo vetra ot massivnyh blizhaishih k chernoi dyre zvezd. Disk vokrug chernoi dyry ne obrazuetsya - zahvatyvaetsya tol'ko veshestvo dvizhusheesya pochti radial'no i zahvatyvaemoe chernoi dyroi.


obzor astro-ph/0311621 Teoriya dzhetov, porozhdaemyh magnitnymi diskami (Theory of magnetized accretion discs driving jets)
Authors: Jonathan Ferreira
Comments: 40 pages, 6 figures, EDP Sciences, p.229-277, 2002

Podrobnaya analiticheskaya(!) teoriya togo, kak akkrecionnye diski s magnitnym polem porozhdayut dzhety. Rassmotreny sleduyushie voprosy:

  • magnitnye akkrecionno-ezhekcionnye struktury;
  • magnitnye dzhety;
  • dzhety, sozdannye diskami;
  • avtomodel'nye resheniya;
  • "holodnye" i "teplye" konfiguracii;
  • nablyudatel'nye predskazaniya.


Vypusk 59. 19-31 oktyabrya 2003

astro-ph/0310617 Holodnyi akkrecionnyi disk v ul'tramoshnom istochnike X-9 v M81: ukazaniya na chernuyu dyru promezhutochnoi massy (Revealing a Cool Accretion Disk in the Ultraluminous X-ray Source M81 X-9 (Holmberg IX X-1): Evidence for an Intermediate Mass Black Hole)
Authors: J. M. Miller et al.
Comments: 8 pages, 6 figres, 3 in color, uses emulateapj.sty and apjfonts.sty submitted to ApJ

Napomnim, chto eshe neskol'ko let nazad elementom standartnoi kartiny byli tri tipa chernyh dyr: pervichnye (naibolee mnogochislennye na segodnyashnii den' dolzhny imet' massu poryadka 1015 g.), ostavshiesya ot rannei epohi zhizni Vselennoi, zvezdnye (massoi poryadka 5-10 mass Solnca), obrazovavshiesya iz massivnyh zvezd v rezul'tate kollapsa, i sverhmassivnye (s massami ot 106 do 1010 mass Solnca). V poslednee vremya poyavlyayutsya razlichnye ukazaniya na sushestvovanie chernyh dyr promezhutochnyh mass v sotni mass Solnca. Odnimi iz kandidatov v takie ob'ekty yavlyayutsya t.n. sverhmoshnye (Ultraluminous) rentgenovskie istochniki.

V dannoi rabote avtory issledovali spektr odnogo iz takih istochnikov. Odna iz komponent spektra interpretiruetsya kak vklad holodnogo (po merkam akkrecii na kompaktnye ob'ekty) diska s temperaturoi 0.17-0.29 keV. Masshtabirovanie svoistv diskov izvestnyh galakticheskih kandidatov v chernye dyry privodit k sleduyushemu rezul'tatu: my vidim akkreciyu na chernuyu dyru s massoi poryadka 1000 mass Solnca.

Konechno, eto model'nyi rezul'tat. Neobhodimy dal'neishie issledovaniya. No tak ili inache, a svoistva istochnika X-9 v M81 yavlyayutsya ser'eznym argumentom. Storonnikam anizotropnogo izlucheniya pridetsya potruditsya, chtoby ob'yasnit' dannye nablyudeniya bez privlecheniya stol' massivnoi chernoi dyry.


gr-qc/0310107 Ustoichivye gravizvezdy - al'ternativa chernym dyram? (Stable gravastars - an alternative to black holes?)
Authors: Matt Visser, David L. Wiltshire
Comments: 19 pages, 5 figures; uses iopart.cls, setstack.sty

Nedavno v SMI (vklyuchaya Scientific American) proshla novost' (podannaya v neskol'ko preuvelichennom klyuche) o rabote Mazura i Mottoly po al'ternative chernym dyram. Avtory predlozhili model', v kotoroi blagodarya fazovomu perehodu v sostoyanie ves'ma specificheskogo kondensata obrazuetsya ob'ekt bez singulyarnosti, gorizonta sobytii i t.p. Takzhe avtory polagayut, chto oni reshili tem samym problemu bol'shoi entropii chernyh dyr. Sami Mazur i Mottola rassmotreli lish' teplovuyu ustoichivost' naidennogo imi resheniya. V dannoi rabote Visser i Viltshir rassmatrivayut dinamicheskuyu ustoichivost' resheniya, podobnogo poluchennomu Mazurom i Motolloi.


Vypusk 58. 01-17 oktyabrya 2003

astro-ph/0310045 Para dvoinyh radiogalaktik - ostatki sliyaniya dvoinyh sverhmassivnyh chernyh dyr (Double-double radio galaxies: remnants of merger of supermassive binary black holes)
Authors: F.K. Liu et al.
Comments: 6 pages, 2 figures, MNRAS, 340 (2003) 411

Iz centrov radiogalaktik v protivopolozhnyh napravleniya vybrasyvayutsya dva puchka relyativistskih chastic, kotorye na nekotorom rasstoyanii ot galaktiki tormozyatsya i obrazuyut vidimye v radiodiapazone "radioushi". Odna iz teorii polagaet, chto podobnaya aktivnost' yavlyaetsya rezul'tatom sliyaniya v centre galaktiki dvuh sverhmassivnyh chernyh dyr neravnoi massy. V dannoi stat'e podrobno rassmotren sluchai galaktiki s kotoroi svyazan radioistochnik B1834+620.


miniobzor astro-ph/0310070 Relyativistskii kollaps vrashayushihsya sverhmassivnyh zvezd v sverhmassivnye chernye dyry (Relativistic Collapse of Rotating Supermassive Stars to Supermassive Black Holes)
Authors: Stuart L. Shapiro
Comments: 11 pages, 6 figures

V principe zvezdy mogut imet' ochen' bol'shuyu massu - do milliona mass Solnca i vyshe. Davlenie v etih zvezdah opredelyaetsya izlucheniem, ih vremya zhizni perestaet zaviset' ot massy i sostavlyaet okolo milliona let. Takie zvezdy ne sovsem ustoichivy: oni pul'siruyut, intensivno teryayut veshestvo v vide vetra, no za vremya zhizni zvezdy ee massa umen'shaetsya neznachitel'no. Zhizn' podobnoi sverhmassivnoi zvezdy zakanchivaetsya ee kollapsom i obrazovaniem sverhmassivnoi chernoi dyry. Takie idei byli populyarny vo vtoroi polovine 60-h godov (togda sverhmassivnye zvezdy nazyvali "magnitarami"). Sverhmassivnymi zvezdami togda pytalis' ob'yasnit' fenomen kvazarov.

Segodnya, s obnaruzheniem v centrah galaktik (dazhe na bol'shih z) bol'shogo chisla sverhmassivnyh chernyh dyr, interes k sverhmassivnym zvezdam vozrodilsya snova. O rezul'tatah modelirovaniya sverhmassivnyh zvezd i ih kollapsa v ramkah obshei teorii otnositel'nosti rasskazyvaet Styuart Shapiro.


astro-ph/0310267 Kosmologicheskaya evolyuciya mass chernyh dyr v kvazarah (The cosmological evolution of quasar black-hole masses)
Authors: R.J.McLure, J.S. Dunlop
Comments: 15 pages, 10 figures, submitted to MNRAS

Po dannym Sloanovskogo cifrovogo obzora neba polucheny virial'nye ocenki mass chernyh dyr bolee chem v 12000(!) kvazarov s 0.1<z<2.1. Eti massy lezhat v intervale ot 107Mo do 3x109Mo, t.e. ne prevyshayut massy samyh bol'shih chernyh dyr, nablyudaemyh v centrah galaktik. Bolee togo, bolometricheskaya svetimost' kvazarov ne prevoshodit eddingtonovskii predel, sootvetstvuyushii ocenkam mass nahodyashihsya v nih chernyh dyr.

Otdel'noe issledovanie vyborki kvazarov s 1.9<z<2.1 pokazalo, chto bol'shinstvo chernyh dyr s M>3x108Mo sushestvovalo uzhe togda.

Raspredelenie 1069 kvazarov c 1.9<z<2.1 po absolyutnoi zvezdnoi velichine. Chernaya gistogramma pokazyvaet analogichnoe raspredelenie podmnozhestva kvazarov, ch'ya massa prevyshaet ukazannyi na risunke porog.


Vypusk 57. 22-30 sentyabrya

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.


Vypusk 56. 13-20 sentyabrya 2003

astro-ph/0309458 Model' dlya vysokochastotnyh kvaziperiodicheskih oscillyacii v Akkreciruyushih chernyh dyrah (A Model for High Frequency Quasi-periodic Oscillations from Accreting Black Holes)
Authors: Jeremy D. Schnittman and Edmund Bertschinger
Comments: 25 pages, 13 figures, submitted to ApJ

Nablyudeniya s borta rentgenovskogo sputnika RXTE obnaruzhili vysokochastotnye kvaziperiodicheskie oscillyacii (QPO) u ryada akkreciruyushih rentgenovskih sistem s chernymi dyrami. Po krainei mere u dvuh sistem kolebaniya proishodyat na dvuh chastotah, otnosyashihsya kak 2:3. Dlya ob'yasneniya etogo yavleniya avtory predlozhili model' yarkogo pyatna vo vnutrennei chasti akkrecionnogo diska vokrug kerrovskoi chernoi dyry. Vblizi vnutrennego kraya diska, okolo poslednei ustoichivoi krugovoi orbity, chastoty radial'nyh kolebanii obrashayusheisya chasticy sostavlyayut 1/3 orbital'noi chastoty. Nablyudenie podobnogo pyatna pod nekotorym uglom k disku dolzhno porozhdat' kvaziperiodicheskie oscillyacii s otnosheniyami chastot 2:3 ili 3:4.


Vypusk 54. 23-31 avgusta 2003
obzor astro-ph/0308402 Chernye dyry promezhutochnyh mass (Intermediate-Mass Black Holes)
Authors: M. Coleman Miller, E.J.M Colbert
Comments: 68 pages, 14 figures, invited review submitted to International Journal of Modern Physics D. Version with higher quality figures at http://www.astro.umd.edu/~miller/imbh.ps

Kak izvestno, do nedavnego vremeni rassmatrivali tri osnovnyh tipa chernyh dyr.
1. Chernye dyry zvezdnyh mass, voznikayushie v konce evolyucii naibolee massivnyh zvezd. Est' dovol'no mnogo horoshih kandidatov (na russkom yazyke sm. obzor Cherepashuka v UFN).
2. Sverhmassivnye chernye dyry v centrah galaktik. Est' okolo sotni ocenok massy dlya takih ob'ektov (sm. mnozhestvo obzorov v spiske).
3. Pervichnye chernye dyry. Gipoteticheskie ob'ekty ochen' malyh mass (menee 1015 g.).
V poslednie neskol'ko let stali poyavlyat'sya dannye, kotorye ukazyvayut na sushestvovanie chernyh dyr s massami ot sta do neskol'kih tysyach solnechnyh mass. Eto t.n. chernye dyry promezhutochnyh mass.

V obzore avtory podrobno razbirayut razlichnye nablyudatel'nye dannye, kotorye mozhno interpretirovat' kak obnaruzhenie takih ob'ektov. S drugoi storony, obsuzhdaetsya i al'ternativnaya interpretaciya.


Vypusk 51. 21-31 iyulya 2003

miniobzor astro-ph/0307426 Sverhmassivnye chernye dyry na bol'shih krasnyh smesheniyah: rentgenovskie nablyudeniya (High Redshift Supermassive Black Holes: X-ray observations)
Authors: Andrea Comastri
Comments: 10 pages, 5 figures. Invited talk to appear in "The Astrophysics of Gravitational Wave Sources" (Maryland, April 2003), AIP in press, J. Centrella (ed)

Uzhe neskol'ko desyatiletii pered astrofizikoi vysokih energii stoit problema rentgenovskogo fonovogo izlucheniya. Po mere rosta chuvstvitel'nosti i razresheniya detektorov (a zatem i teleskopov), registriruyushih zhestkoe izluchenie, iz fona vydelyalis' i vychitalis' snachala tochechnye galakticheskie istochniki, zatem skopleniya galaktik i kvazary. Bol'shoi progress v etom voprose dostignut blagodarya nablyudeniyam s rentgenovskih observatorii Chandra i XMM, no do sih por chto-to eshe ostaetsya: s pomosh'yu sputnika Chandra okolo 90 procentov rentgenovskogo fona udalos' razreshit' na otdel'nye tochechnye istochniki. V osnovnom eto vnegalakticheskie ob'ekty. A tochnee - aktivnye yadra galaktik. Dannye sputnika HMM-N'yuton pozvolili poluchit' rentgenovskie spektry dlya ryada takih slabyh istochnikov.

V stat'e daetsya obzor po dannym o slabyh rentgenovskih istochnikah - aktivnyh yadrah galaktik. Osobyi upor delaetsya na "istorii akkrecionnoi svetimosti Vselennoi" (sm. risunok).


Raspredelenie aktivnyh yader galaktik po krasnomu smesheniyu. Verhnyaya gistogramma - vse istochniki iz obshei vyborki Chandry i HMM-N'yuton. Krasnaya zashtrihovannaya oblast' - opticheski otozhdestvlennye istochniki. Sploshnaya krivaya - rezul'taty modelirovaniya.


Vypusk 50. 8-18 iyulya 2003

astro-ph/0307110 Nablyudeniya yarchaishei rentgenovskoi vspyshki ot SgrA* na XMM-Newton (XMM-Newton observation of the brightest X-ray flare detected so far from SgrA*)
Authors: D. Porquet et al.
Comments: Accepted for publication in A&A Letters. 4 pages, 2 figures, 1 tables

V centre nashei Galaktiki nahoditsya sverhmassivnaya chernaya dyra s massoi okolo 2-3 millionov mass Solnca. Kak izvestno, chernye dyry akkreciruyut okruzhayushee veshestvo, chto obychno privodit k poyavleniyu rentgenovskogo istochnika. Nashe galakticheskoe yadro v etom smysle yavlyaetsya ochen' neaktivnym: svetimost' chernoi dyry sostavlyaet poryadka odnoi desyatimillionnoi ot predel'noi svetimosti. Eto ochen' malo. Teoretikam prishlos' nemalo potrudit'sya, chtoby pridumat', kak mozhno ob'yasnit' takoe polozhenie del. Kak obychno teoretiki perestaralis': predlozheno neskol'ko mehanizmov, ob'yasnyayushih nizkuyu effektivnost' akkrecii. Kratko opishem dva mehanizma. Pervyi - advekciya. V etom sluchae goryachee veshestvo utekaet pod gorizont, ne uspev izluchit' zapasennuyu energiyu. Vtoroi - strui. Energiya unositsya ne elektromagnitnym izlucheniem, a perehodit v kineticheskuyu energiyu strui (ob etih mehanizmah my neodnokratno pisali - sm. arhiv nashih obzorov, temy "akkreciya" i "chernye dyry"). Vydelit' kakoi iz mehanizmov yavlyaetsya "edinstvenno pravil'nym" - ne udaetsya. Neobhodimo nablyudat'...

Nablyudeniya vyyavili interesnyi fenomen - rentgenovskie vspyshki. Vpervye eto bylo zaregistrirovano v 2000 g. na sputnike Chandra. V etoi stat'e avtory predstavlyayut dannye sputnika XMM-Newton po samoi yarkoi vspyshke. Svetimost' ee vse ravno nevelika: 3-4 1035 erg/s. Dlya ob'yasneniya vspyshek takzhe predlozheno neskol'ko mehanizmov. Chem bol'she nablyudenii - tem bol'she ogranichenii na teoreticheskie modeli. Novye nablyudeniya tut osobenno vazhny, t.k. zaregistrirovannaya vspyshka ne tol'ko samaya yarkaya, no ona eshe imeet ochen' myagkii spektr, simmetrichnuyu krivuyu bleska i ne pokazyvaet sushestvennyh spektral'nyh variacii so vremenem. Eto - novyi vyzov teoretikam.


astro-ph/0307260 Magnitogidrodinamicheskie akkrecionnye potoki v Kerrovskoi metrike. I. (Magnetically Driven Accretion Flows in the Kerr Metric I: Models and Overall Structure)
Authors: J.-P. De Villiers, J.F.Hawley, J.H.Krolik
Comments: 29 pages, 15 figures

Veshestvo s pronikayushim v nego magnitnym polem obrazuet akkrecionnyi disk vokrug kerrovskoi chernoi dyry. Chto budet s nim proishodit'? Kak rezul'tat etogo processa zavisit ot uglovogo momenta chernoi dyry? Vse analiticheskie vozmozhnosti otveta na dannye voprosy uzhe davno ischerpany. V dannoi stat'e issledovanie velos' chislennymi metodami. Avtory obnaruzhili, chto pri vseh znacheniyah momenta chernoi dyry v diske mozhno vydelit' odni i te zhe oblasti: osnovnoe telo diska, okruzhayushuyu ego goryachuyu koronu, vnutrennii tor s kanalom vdol' osi vrasheniya i dvuh protivopolozhno napravlennyh shirokih konicheskih dzhetov, v kotoryh veshestvo ottekaet ot chernoi dyry.


Struktura zamagnichennogo akkrecionnogo diska.

Bolee detal'nye kartinki i animirovannye rezul'taty raschetov mozhno naiti na saite avtorov http://www.astro.virginia.edu/~jd5v/KD_movies.htm.

Ochen' blizkim voprosam chislennogo modelirovaniya magnitogidrodinamicheskih akkrecionnyh potokov posvyashena eshe bolee krasochnaya stat'ya astro-ph/0307306.


miniobzor astro-ph/0307307 Kandidaty v chernye dyry (Black Hole Candidates)
Authors: Janusz Ziolkowski
Comments: 21 pages; review presented at Vulcano Workshop 2002

Spisok kandidatov v chernye dyry v dvoinyh sistemah rastet (sravnite s obzorom Cherepashuka i preprintom astro-ph/0306213). V etoi stat'e ih uzhe 51.

Obzor mozhno ispol'zovat' kak spravochnik: v nem privedena obshaya tablica dannyh dlya vseh kandidatov, a zatem kommentarii dlya kazhdogo ob'ekta individual'no.


astro-ph/0307327 Evolyuciya massivnyh dvoinyh chernyh dyr (Evolution of Massive Black Hole Binaries)
Authors: Junichiro Makino and Yoko Funato
Comments: 27 pages, 11 figures. Submitted to ApJ

Rech' idet o (sverh)massivnyh chernyh dyrah nablyudaemyh v centrah galaktik. Rezul'taty dannoi stat'i polucheny v hode ryada chislennyh eksperimentov, provedennyh na specializirovannyh komp'yuterah Grape. (Eti komp'yutery prednaznacheny dlya resheniya zadach ob evolyucii sistem N tyagoteyushih tochek. Deistviya dlya takih vychislenii realizovany v nih apparatno. V nastoyashee vremya vozmozhny raschety sistem s chislom tochek do N=106, t.e. uzhe mozhno tochno rasschityvat' evolyuciyu sharovyh skoplenii i bolee melkih zvezdnyh sistem.)

Chto proishodit s central'nymi chernymi dyrami, esli galaktiki v kotoryh oni nahodilis', slivayutsya? Raschety podtverdili rezul'taty teoreticheskih ocenok, chto dve sverhmassivnye chernye ne uspevayut slit'sya za habblovskoe vremya bez vliyaniya fona okruzhayushih zvezd (bez dinamicheskogo treniya).



Vypusk 47. 16-21 iyunya 2003


gr-qc/0306082 Effektivnyi metod poiska zvona chernyh dyr (An Effective Search Method for Gravitational Ringing of Black Holes)
Authors: Hiroyuki Nakano et al.
Comments: 17 pages, 9 figures. Submitted to Phys. Rev. D

Esli kak-to vozmutit' formu chernoi dyry (takoe proishodit pri padenii na chernuyu dyru ili blizkom prolete massivnogo tela, pri sliyanii dvuh chernyh dyr i t.p.), to chernaya dyra budet stremit'sya v ravnovesnomu sostoyaniyu, a "izbavit'sya ot vozmushenii" ona smozhet edinstvennym dostupnym ei sposobom - s pomosh'yu ispuskaniya gravitacionnyh voln. Vozmushenie raspadaetsya na ryad fundamental'nyh mod - sobstvennyh kolebanii chernoi dyry. Podobnoe izluchenie ot chernoi dyry nazyvaetsya "zvonom". Amplituda takih kolebanii mozhet byt' dostatochno velika dlya registracii na lazernyh interferometrah. Prichem obnaruzhenie podobnogo gravitacionnogo izlucheniya budet pryamym dokazatel'stvom sushestvovaniya chernyh dyr.

Avtorami dannoi stat'i postroeno semeistvo shablonov - teoreticheskih profilei signalov - dlya effektivnogo poiska "zvona" chernyh dyr.


obzor astro-ph/0306353 Poisk sverhmassivnyh chernyh dyr v yadrah galaktik po zvezdnoi dinamike (The Stellar-Dynamical Search for Supermassive Black Holes in Galactic Nuclei)
Authors: John Kormendy
Comments: 20 pages, 5 figures + 2 tables embedded as figures, LaTeX2e with wrapping fixed, uses ociwsymp1.sty; To appear in "Carnegie Observatories Astrophysics Series, Vol. 1: Coevolution of Black Holes and Galaxies," ed. L. C. Ho (Cambridge: Cambridge Univ. Press)

Naibolee tochnye opredeleniya mass temnyh ob'ektov v centrah galaktik poluchayutsya po nablyudeniyam zvezd, vrashayushihsya blizko ot nih. V stat'e daetsya ischerpyvayushii obzor po poisku sverhmassivnyh chernyh dyr etim metodom. Seichas est' uzhe neskol'ko galaktik (vklyuchaya nashu i M31), v kotoryh na osnovanii dannyh nablyudenii mozhno isklyuchit' skoplenie temnyh ob'ektov tipa korichnevyh karlikov ili kompaktnyh ostatkov. Fakticheski, eto oznachaet, chto my imeem delo s chernymi dyrami (ili, mozhno procitirovat' Kipa Torna: "Chernaya dyra - eto samaya konservativnaya gipoteza").

Vypusk 46. 1-15 iyunya 2003

astro-ph/0306074 Nuzhna eshe odna chernaya dyra v centre Galaktiki (The need for a second black hole at the Galactic center)
Authors: Brad Hansen, Milos Milosavljevic
Comments: 5 pages, 2 postscript figures, submitted to ApJ letters The introduction section has been updated since submission to ApJ

Pohozhe vse uzhe soglasilis' s nalichiem chernoi dyry massoi primerno 3.106 Mo v centre nashei Galaktiki. Eto utverzhdenie podtverzhdaetsya kak infrakrasnymi nablyudeniyami istochnika Sagitarrius A*, tak i dinamikoi zvezd vnutri central'nogo 0.1 pk.

Voprosy vyzyvaet drugoi fakt - naibolee yarkie zvezdy na rasstoyanii 0.1 pk, sobstvennye dvizheniya kotoryh nablyudayutsya, yavlyayutsya massivnymi i, sledovatel'no, molodymi. Otkuda oni vzyalis'? Tam gde oni nahodyatsya seichas im obrazovat'sya prosto ne iz chego. Priblizit'sya k central'noi chernoi dyre s bOl'shih rasstoyanii (naprimer s 1 pk) pod deistviem dinamicheskogo treniya oni by ne smogli - harakternoe vremya podobnoi diffuzii sushestvenno prevyshaet vremya zhizni massivnyh zvezd.

Avtory dannoi raboty predpolagayut, chto nablyudaemye nami zvezdy byli sbrosheny so svoih orbit za predelami 1 pk chernoi dyroi promezhutochnoi massy (103-104 Mo), obrashayusheisya vokrug centra Galaktiki po dostatochno udalennoi orbite. Podtverzhdeniem sushestvovaniya vtoroi chernoi dyry mozhet posluzhit' obnaruzhenie smesheniya svyazannogo s central'noi chernoi dyroi radioistochnika pod deistviem gravitacii vtoroi dyry. Nesmotrya na to, chto massa vtoroi dyry sostavlyaet dolyu procenta ot central'noi - sovremennaya astrometriya mozhet zaregistrirovat' podobnoe smeshenie.


obzor astro-ph/0306213 Chernye dyry v dvoinyh sistemah (Black Hole Binaries)
Authors: J.E. McClintock, R.A. Remillard
Comments: 62 pages, 20 figures, 4 tables; draft 1 of review

V etom obzore podrobneishim obrazom rassmotreny svoistva rentgenovskih dvoinyh sistem s chernymi dyrami: 18 "sistem s podtverzhdennymi chernymi dyrami" i 22 "kandidata v chernye dyry". (Terminy, ispol'zuemye avtorami, otlichayutsya ot obychno upotreblyaemyh, vyrazhaya uverennost' avtorov v sushestvovanii predmeta o kotorom oni pishut.)


Shematicheskoe (disk+korona) izobrazhenie razlichnyh (po rentgenovskomu spektru i svetimosti) sostoyanii chernyh dyr. Os' sprava pokazyvaet temp akkrecii v edinicah Eddingtonovskogo.

Vot osnovnye punkty obzora: rentgenovskie dvoinye, rentgenovskie novye, akkreciya na chernye dyry, spektry i svetimosti chernyh dyr (po dannym raznyh apparatov), linii izlucheniya zheleza, svreheddingtonovskie svetimosti, razlichnye sostoyaniya rentnyh dyr (rassmotreno podrobno), bystraya peremennost' i kvaziperiodicheskie oscillyacii.


obzor astro-ph/0306214 Dinamika zvezd v central'noi uglovoi sekunde nashei Galaktiki (Stellar dynamics in the central arcsecond of our galaxy)
Authors: R.Schoedel et al.
Comments: 51 pages, 16 Figures, submitted to ApJ

V kruzhke radiusom 1.2" vokrug centra nashei Galaktiki - istochnika Sagittarius A* (Sgr A*) - nablyudaetsya bolee 40 zvezd. Na ih dinamiku vliyaet central'naya chernaya dyra. (Tochnee, naibolee strogim dokazatel'stvom sushestvovaniya central'noi chernoi dyry yavlyaetsya izuchenie dinamiki zvezd naibolee blizkih k centru Galaktiki.) Ob etih issledovaniyah uzhe neodnokratno pisalos', no zdes' vy naidete detal'noe izlozhenie, kak metodik nablyudeniya, tak i rezul'tatov nablyudenii i ih interpretaciyu.

Skorosti zvezd (proporcional'ny dline strelok). Razmer izobrazheniya 2.4"x 2.4". Proekcii vektorov uskoreniya zvezd na kartinnuyu Ploskost' (s 2 konusami). Pokazana oblast' 0.6"x 0.7" vblizi centra.


Vypusk 44. 17-23 maya 2003

astro-ph/0305287 Poslednie vitki vrashayushihsya dvoinyh chernyh dyr (The final plunge of spinning binary black holes)
Authors: J.Baker et al.
Comments: 17 pages, 29 figures

Chernye dyry - ochen' prostye ob'ekty, samaya slozhnaya iz nih v stacionarnom sostoyanii opisyvaetsya vsego tremya parametrami: massoi, uglovym momentom i elektricheskim zaryadom (i/ili magnitnym zaryadom, esli takoi sushestvuet). V kosmose, zapolnennom plazmoi, real'noe znachenie imeyut tol'ko pervye dva iz nih, tak kak akkreciya chastic s zaryadom protivopolozhnogo znaka bystro umen'shaet sobstvennyi elektricheskii zaryad chernoi dyry pochti do nulya.

Dve chernye dyry, obrazuyushie dvoinuyu sistemu, kak i vse drugie dvoinye zvezdy, budut izluchat' gravitacionnye volny. A esli dvoinaya chernaya dyra dostatochno tesnaya, to ee komponenty sblizyatsya i sol'yutsya za vremya men'shee vozrasta Vselennoi. Podobnye sobytiya ochen' interesny tem, kto zanimaetsya poiskom gravitacionnyh voln, poskol'ku chernye dyry s bolee vysokoi, chem u neitronnyh zvezd, massoi, budut bolee moshnymi istochnikami gravitacionnogo izlucheniya i ih mozhno budet obnaruzhivat' s bOl'shih rasstoyanii.

Kakim momentom vrasheniya (a) budut obladat' chernye dyry, vhodyashie v dvoinuyu sistemu, zavisit ot hoda ih evolyucii. Odnako, chernaya dyry, obrazuyushayasya v rezul'tate ih sliyaniya, obyazatel'no budet bystro vrashat'sya, poskol'ku ei "po nasledstvu" dostanetsya moment impul'sa orbital'nogo dvizheniya. Esli slivayutsya dve Shvarcshil'dovskie chernye dyry (nevrashayushiesya, s a=0), to chernaya dyry, obrazuyushayasya v rezul'tate ih sliyaniya, budet imet' vysokii moment

Sliyanie Kerrovskih chernyh dyr etot parametr mozhet umen'shit' ili uvelichit', v zavisimost' ot vzaimnoi orientacii orbital'nogo i sobstvennyh momentov impul'sov v sisteme:

Iz privedennogo sootnosheniya vidno, chto v takom processe mogut obrazovyvat'sya dazhe predel'no bystro vrashayushiesya chernye dyry s a/M=1. Konechno, eto skazyvaetsya i na forme gravitacionno-volnovyh impul'sov, chto vazhno dlya ih registracii.


astro-ph/0305335 Shema edinogo opisaniya malomoshnyh akkreciruyushih chernyh dyr - struino-dominirovannye akkrecionnye potoki i korrelyaciya radio i rentgenovskogo izlucheniya (A Scheme to Unify Low-Power Accreting Black Holes - Jet-Dominated Accretion Flows and the Radio/X-Ray Correlation)
Authors: Heino Falcke et al.
Comments: Astronomy & Astrophysics, submitted, A&A LaTex, 7 pages, 3 figures, also available at this URL

Odna iz celei nauchnogo podhoda - opisanie nablyudaemyh yavlenii s tochki zreniya naibolee obshego (edinogo ) podhoda. Otsyuda poiski "teorii vsego", "Velikoe ob'ekdinenie" i t.d. Pohozhie veshi proishodyat vo vseh oblastyah nauki. V astronomii, naprimer, pytayutsya ob'yasnit' aktivnost' galaktik raznyh tipov v terminah evolyucionnyh stadii sverhmassivnyh chernyh dyr.

Akkreciruyushie chernye dyry vstrechayutsya ne tol'ko v yadrah galaktik. Est' takie ob'ekty v tesnyh dvoinyh sistemah. Po vsei vidimosti est' chernye dyry promezhutochnyh mass. Dolzhny byt' odinochnye chernye dyry, akkreciruyushie veshestvo mezhzvezdnoi sredy... Processy dolzhny byt' v kakoi-to stepeni pohozhi (o raznyh tipah chernyh dyr sm., naprimer, obzory Cherepashuka v UFN). V dannoi stat'e avtory predstavlyayut popytku edinogo opisaniya razlichnyh ob'ektov, soderzhashih akkreciruyushie chernye dyry, ch'ya svetimost' sushestvenno men'she eddingtonovskoi. Raznica v tom, chto pri svetimosti poryadka eddingtonovskoi dominiruet vklad diska, a pri sushestvenno men'shei svetimosti - neteplovoe izluchenie relyativistskogo dzheta. Kandidatov v takoe sostoyanie mnogo: ot tesnyh dvoinyh do aktivnyh i neaktivnyh yader galaktik.

Osnovnye predpolozheniya avtorov svodyatsya k tomu, chto
dzhet vsegda prisutstvuet,
pri nekotorom tempe akkrecii (menee neskol'kih procentov ot eddingtonovskogo) disk perestaet byt' sushestvennym istochnikom izlucheniya,
esli my smotrim "v zherlo", to vklad dzheta bol'she vklada diska.

Sravnenie s nablyudeniyami pokazyvaet rabotosposobnost' modeli, odnako yasno, chto ona nuzhdaetsya v dal'neishem razvitii i novyh proverkah, poskol'ku ochevidno, chto real'nost' ustroena neskol'ko slozhnee, chem prosto tonkii disk + dzhet.


Vypusk 42. 1-9 maya 2003


astro-ph/0305061 Skvizary: zvezdy prilivnogo vozbuzhdeniya na orbitah vokrug sverhmassivnyh chernyh dyr (Squeezars: Tidally powered stars orbiting a massive black hole)
Authors: Tal Alexander, Mark Morris
Comments: ApJ Lett. accepted. 4 pp. 1 fig

Avtory vvodyat novyi tip tranzientnyh (vspyhivayushih) istochnikov. Eto zvezdy, vrashayushiesya na sil'noekscentrichnyh (sil'no vytyanutyh) orbitah vokrug sverhmassivnyh chernyh dyr s massoi do 108 mass Solnca. Takoi predel svyazan s tem, chto chem men'she chernaya dyra - tem bol'she prilivnye sily na tom zhe rasstoyanii ot nee (esli rasstoyaniya izmeryat' v radiusah chernoi dyry). Zvezdy, proletaya vblizi chernoi dyry, budut ispytyvat' moshnoe prilivnoe vozdeistvie, chto budet privodit k sushestvennomu vozrastaniyu ih svetimosti (vplot't do eddingtonovskogo predela).

Avtory stroyat modeli takih zvezd i ocenivayut temp poyavleniya sobitii. On okazyvaetsya nebol'shim, no avtory nadeyutsya, chto vysokaya svetimost' pozvolit uvidet' takie "skvizary" (szhvezdy"? - ot slova "szhimat'") dazhe pri nizkom tempe vspyshek.

Sm. takzhe vtoruyu stat'yu teh zhe avtorov: "Orbital inspiral into a massive black hole in a galactic center".


Vypusk 41. 25-30 aprelya 2003

astro-ph/0304528 Uluchshennyi predel na plotnost' pervichnyh chernyh dyr (An improved gamma-ray limit on the density of PBHs)
Authors: A. Barrau, G. Boudoul, L. Derome
Comments: 4 pages, To appear in the 28th ICRC conference proceedings

Kak izvestno, v astronomii rassmatrivayut chetyre osnovnyh tipa chernyh dyr: zvezdnye, svehmassivnye, promezhutochnyh mass (nedavno obnaruzheny ser'eznye ukazaniya na ih sushestvovanie) i pervichnye. Zaregistrirovat' poslednie trudno vvidu ih maloi massy (i nebol'shogo chisla). Tut moglo by pomoch' isparenie chernyh dyr. Kroshechnye chernye dyry dolzhny mnogo izluchat'. Imenno ishodya iz gipotezy ob isparenii mozhno dat' verhnii predel na prostranstvennuyu plotnost' (t.e. kolichestvo ob'ektov na, skazhem, kubicheskii parsek) pervichnyh chernyh dyr. V etoi rabote avtory dayut novyi, bolee zhestkii, predel: v pervichnyh chernyh dyrah ne mozhet byt' bol'she 3.3 10-9 ot polnoi plotnosti Vselennoi.

Na samom dele, vozmozhnost' ispareniya chernyh dyr lyuboi massy yavlyaetsya lish' vozmozhnost'yu. Esli malen'kie chernye dyry ne isparyayutsya (ili isparyayutsya kak-to maloeffektivno), to ih vklad v massu Vselennoi mozhet byt' gorazdo vyshe (sm. podrobnyi obzor na etu temu).

astro-ph/0304514 Plotnost' massy blizkih chernyh dyr po obzoru radiogalaktik 2dFGRS (The local black-hole mass function from 2dFGRS radio galaxies)
Authors: Elaine M. Sadler
Comments: 6 pages, 3 figures.

Dlya ochen' mnogih radiogalaktik rannih tipov (E i S0) imeyutsya ukazaniya na nalichie v ih centrah sverhmassivnyh chernyh dyr. Esli verna gipoteza o tom, chto massy takih chernyh dyr korreliruyut s radiosvetimostyami galaktik, to predstavlyaetsya prekrasnaya vozmozhnost' vospol'zovat'sya bol'shoi vyborkoi takih galaktik iz radioobzora krasnyh smeshenii (2dF Galaxy Redshift Survey = 2dFGRS), chtoby ocenit' massy blizkih (do z<0.1) chernyh dyr. Takaya rabota byla provedena, prakticheski radi odnogo chisla, srednei plotnosti chernyh dyr v nashih okrestnostyah. Itak: vblizi nas srednyaya plotnost' sverhmassivnyh chernyh dyr sostavlyaet (pri znachenii postoyannoi Habbla H0=50 km/s/Mpk)

Eto znachenie horosho soglasuetsya s drugimi ocenkami i podtverzhdaet predpolozhenie, chto blizkie radiogalaktiki yavlyayutsya pryamymi potomkami bol'shinstva ili vseh kvazarov.



diplom astro-ph/0304478 Gamma-izluchenie pervichnyh chernyh dyr v supersimmetrichnyh scenariyah (Gamma Rays from Primordial Black Holes in Supersymmetric Scenarios)
Authors: Martin Sahlen
Comments: Master's Thesis. 77 pages, 23 figures

Mnogie diplomy (osobenno na Zapade) imeyut otlichnuyu obzornuyu chast'. T.e. mozhet samo original'noe issledovanie studenta ne vsegda zasluzhivaet ochen' vnimatel'nogo prochteniya, no Vvedenie (kotoroe mozhet zanimat' bOl'shuyu chast' raboty) - vpolne zasluzhivaet. Ne beremsya sudit' o nauchnoi znachimosti dannoi publikacii, odnako, rekomenduem vvodnye chasti kak otnositel'no populyarnoe vvedenie v fiziku i astrofiziku pervichnyh chernyh dyr.


Vypusk 39. 12-18 aprelya 2003


obzor gr-qc/0304042 Izluchayut li chernye dyry? (Do black holes radiate?)
Authors: Adam D. Helfer
Comments: review article, 80 pp., 3 included eps figures, IOP macros (included)

Bol'shoi podrobnyi obzor po izlucheniyu chernyh dyr, neperegruzhennyi formulami i ssylkami. Sut' obzora v podrobnom obsuzhdenii trudnostei, imeyushihsya v opisanii ispareniya chernyh dyr (Houkingovskoe izluchenie). Delo v tom, chto krome togo chto izluchenie poka ne obnaruzheno, sam fakt ego vozmozhnosti pod voprosom, t.k. vyvody ob isparenii chernyh dyr baziruyutsya na ryade predpolozhenii. Drugoi vybor razumnyh parametrov delaet izluchenie chernyh dyr nevozmozhnym. Takzhe vse bolee populyarnoi stanovitsya ideya, chto sovsem malen'kie chernye dyry (s massoi poryadka Plankovskoi - 2.2 10-5g) ne izluchayut. Sootvetstvenno, dazhe esli izluchenie est', dyry ne isparyayutsya do konca. Ostavshiesya relikty mogut vnosit' vklad v temnuyu materiyu. (Sm. takzhe raboty Alekseeva i dr.).


astro-ph/0304202 Obrazovanie sverhmassivnyh chernyh dyr: modelirovanie v OTO (Formation of Supermassive Black Holes: Simulations in General Relativity)
Authors: Stuart L. Shapiro
Comments: To appear in "Carnegie Observatories Astrophysics Series, Vol. 1: Coevolution of Black Holes and Galaxies," ed. L. C. Ho (Cambridge: Cambridge Univ. Press). (17 pages, 8 figures)

Nesmotrya na to, chto sushestvovanie sverhmassivnyh chernyh dyr v central'nyh oblastyah mnozhestva galaktik uzhe fakticheski ne vyzyvaet somneniya, mehanizm formirovaniya chernyh dyr ostaetsya neizvestnym (eto bylo "goryachei temoi" na proshloi nedele). Vsem yasno, kak chernaya dyra mozhet uvelichivat' svoyu massu - akkreciya. No vot otkuda beretsya "zarodysh" chernoi dyry?

Shapiro rassmatrivaet neskol'ko populyarnyh scenariev: kollaps sverhmassivnoi zvezdy, kollaps zvezdnogo skopleniya ili oblaka chastic (temnoi materii) i dr. Dlya resheniya etih zadach trebuetsya primenenie Obshei teorii otnositel'nosti (OTO). Poetomu nuzhny moshnye komp'yuternye metody. O prodelannyh raschetah i rasskazyvaetsya v rabote.


(Arhiv Chernye dyry:
v.2, 2004, v.1, 2002-2003)

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