The R.A.P. Project (Reviews of Astro-Ph)
Tesnye dvoinye sistemy
Authors: Guillaume Dubus, Robert E. Rutledge
Comments: 5 pages, 4 figures, accepted for publication in MNRAS
V central'noi oblasti M33 nahoditsya samyi moshnyi stacionarnyi rentgenovskii istochnik v Mestnoi gruppe. Novye nablyudeniya na Chandre ne podtverzhdayut predydushie nablyudeniya, govorivshie o tom, chto ob'ekt smeshen ot centra galaktiki na 1". T.e. ob'ekt nahoditsya v yadre (v predelah tochnosti Chandry). Istochnik ochen' pohozh na Galakticheskii mikrokvazar GRS 1915+105.
Otmetim, chto istochnik ne yavlyaetsya sverhmassivnoi chernoi dyroi.
Voobshe galaktika M33 ne imeet sverhmassivnogo ob'ekta v centre.
Author: T. Di Salvo, L. Stella
Comments: 11 pages, including 4 figures. To appear in the proceedings of the XXII Moriond Astrophysics Meeting "The Gamma-Ray Universe" (Les Arcs, March 9-16, 2002), eds. A. Goldwurm, D. Neumann, and J. Tran Thanh Van, The Gioi Publishers (Vietnam)
Daetsya obzor sovremennogo sostoyaniya del v izuchenii zhestkogo rentgenovskogo
izlucheniya ot malomassivnyh rentgenovskih
dvoinyh
sistem.
Provoditsya sravnenie sistem s neitronnymi zvezdami i chernymi dyrami.
Obsuzhdayutsya perspektivy, svyazannye s zapuskom sputnika INTEGRAL
(napomnim, chto 25 procentov nablyudatel'nogo vremeni na etom apparate
prinadlezhit Rossii).
Author: W. Coburn et al.
Comments: 36 Pages, 9 Figures, 9 Tables, ApJ in press
Odnim iz vazhneishii parametrov neitronnyh zvezd yavlyaetsya velichina ih magnitnogo polya. Dlya radiopul'sarov pole opredelyaetsya v osnovnom po tempu zamedleniya v predpolozhenii magnito-dipol'nogo izlucheniya. Dlya rentgenovskih pul'sarov (o kotoryh i idet rech' v stat'e) mozhno ispol'zovat' kak dannye po uskoreniyu i zamedleniyu, tak i pryamye spektral'nye dannye. Togda po ciklotronnoi linii mozhno opredelit' velichinu polya.
V stat'e avtory ispol'zuyut dannye, poluchennye na sputnike RXTE, dlya 10 rentgenovskih pul'sarov. Krome dannyh po magnitnym polyam avtory issledovali korrelyacii mezhdu razlichnymi parametrami, naprimer izuchalos' vlichnie magnitnogo polya na harakteristkii rentgenovskogo izlucheniya.
Authors: Ronald A. Remillard et al.
Comments: 11 pages, 5 figs.; Procs. of the 4th Microquasar Workshop, 2002, eds. Durouchoux, Fuchs, & Rodriguez, (Center for Physics: Kolkata)
V rentgenovskom diapazone (da i ne tol'ko v nem) sushestvuyut slozhnosti s opredeleniem parametrov istochnikov. Banal'nyi primer. Na Zemle my izmeryaem potok, no chotby poluchit' svetimost' neobhodimo tochno znat' rasstoyanie, a ono chasto izvestno ploho ili ochen' ploho. Est' problemu so spektrami, osobenno s osobennostyami (liniyami). Spektry chasto okazyvayutsya model'nozavisimymi. I lish' vremennye harakteristiki izmeryayutsya tochno. Poetomu ih vse tak lyubyat. Samye prostye istochniki v etom smysle - rentgenovskie pul'sary. Period pul'sacii - period vrasheniya neitronnoi zvezdy. No est' i vsyakie drugie "zveri", naprimer istochniki s t.n. kvaziperiodicheskimi oscillyaciyami (KPO).
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KPO proyavlyayut sebya na t.n. spektrah moshnosti. Na takih grafikah (sm.
risunok) po gorizontal'noi osi chastota, po vertikal'noi - "moshnost'"
(ne budet vdavat'sya v detali). Pokazany spektry dlya treh ob'ektov.
Vidno, chto gde-to est' yavnye "pichki", gde-to menee yavnye.
Tak ili inache, no oni svidetel'stvuyut o nalichii nekotoryh harakternyh
chastot. Vot po etim dannym i pytayutsya ponyat' chto zhe proishodit v istochnike.
Est' mnozhestvo modelei KPO. Delo v tom, chto eto yavlenie nablyudaetsya i dlya neitronnyh zvezd i dlya chernyh dyr akkreciruyushih v dvoinyh sistemah. No kakaya raznica! U neitronnyh zvezd i vam poverhnost', i vam magnitnoe pole. A dyra - ona i est' dyra. Odnako, hotelos' by postroit' edinuyu model' KPO. V obzore rech' idet o KPO v dvoinyh sistemah s chernymi dyrami. V osnovnom o nablyudeniyah. |
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Authors: Janusz Zi\'o{\l}kowski
Comments: 6 pages, 1 figure; review presented at Vulcano Workshop: "Multifrequency Behaviour of High Energy Cosmic Sources" (Vulcano, May 21-26, 2001). To be published in Memorie della Societa Astronomica Italiana, 2
Daetsya obzor tesnyh dvoinyh sistem s Be-zvezdami. Eto massivnye zvezdy s emissionnymi liniyami, chto svyazano s ih bystrym vrasheniem vokrug svoei osi. Pri etom obrauetsya istekayushii disk. Vtorym kompan'onom kak pravilo yavlyaetsya neitronnaya zvezda. Sistemy nablyudayutsya v rentgenovskom diapazone kak tranzientnye istochniki.
Authors: Duncan K. Galloway et al.
Comments: 13 pages, 7 figures, submitted to ApJ
Odna iz vazhnyh zadach v astronomii - poisk t.n. "standartnyh svechei". Esli vy uvereny v svetimosti ob'ekta, to, znaya potok na Zemle, mozhno opredelit' rasstoyanie. V dannoi stat'e avtory predlagayut ispol'zovat' rentgenovsike barstery v kachestve standartnyh svechei. Na primere istochnika 4U 1728-34 Gellouei i dr. popytalis' opredelit' "standart", i po ih slovam eto udalos' sdelat' s 3-h procentnoi tochnost'yu. Edinstvennoi sushestvennoi neopredelennost'yu, po mneniyu avtorov, okazalas' neizvestnaya massa neitronnoi zvezdy. K schast'yu, diapazon etot ne velik, i ocenka rasstoyaniya do istochnika s uchetom neopredelennostei okazavaetsya ravnoi 5.2-5.6 kpk.
Authors: Jerome A. Orosz
Comments: nvited talk at IAU Symp. 212, "A Massive Star Odyssey, from Main Sequence to Supernova", to appear in the proceedings (K. A. van der Hucht, A. Herraro, & C. Esteban eds., San Francisco: ASP), 7 pages, 1 figure, 1 sideways table
Obsuzhdayutsya dvoinye sistemy s chernymi dyrami. Seichas est' uzhe 17 par, gde massa kompaktnogo ob'ekta slishkom velika dlya neitronnoi zvezdy. Osoboe vnimanie avtor udelyaet opticheskim nablyudeniyam kandidatov v chernye dyry.
Authors: L. Foschini et al.
Comments: 4 pages, no figures. Presented at AGN05: Inflows, Outflows and Reprocessing around black holes, Como (Italy), 11-14 June 2002. To appear in the Proceedings
Daetsya obzor po t.n. sverhyarkim (ultraluminous) rentgenovskim istochnikam. Prichina ih naimenovaniya kroetsya v tom, chto svetimost' istochnikov prevoshodit eddingtonovskuyu dlya zvezdnyh mass. Rassmatrivayutsya razlichnye gipotezy, ob'yasnyayushie prirodu etih ob'ektov.
Ob obnaruzhenii odnogo ochen' interesnogo ob'ekta dannogo tipa sm. astro-ph/0209292.
Authors: A.D. Schwope, H. Brunner, D. Buckley, J. Greiner, K. v.d. Heyden, S. Neizvestny, S. Potter, R. Schwarz
Comments:Astronomy and Astrophys., in press, 17 pages, 19 figures, full paper with finding charts at http://www.aip.de/People/ASchwope/axels_papers.html
"Navstrechu perepisi naseleniya!" Avtory predstavlyayut perepis' kataklizmicheskih peremennyh (eto tesnye dvoinye s belymi karlikami) po dannym nablyudenii v rentgenovskom diapazone na sputnike ROSAT.
Authors: Massimo Della Valle
Comments: Invited Review (14 pag.). To appear in the Proceedings of the Conference lassical 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: 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: I.F. Mirabel
Commets: 10 pages, 2 figures. Invited review at the IAU Symposium No.214: High Energy Processes and Phenomena in Astrophysics
Mikrokvazary - eto tesnye dvoinye sistemy s akkreciruyushimi kompaktnymi ob'ektami (po vsei vidimosti s chernymi dyrami), gde krome obychnoi v takih sluchayah aktivnosti takzhe nablyudayutsya struinye vybrosy (dzhety). Avtor (kstati, termin "mikrokvazar" prinadlezhit emu) posledovatel'no provodit analogii mezhdu mikrokvazarami i razlichnymi istochnikami vysokoenergichnogo izlucheniya. Obzor ochen' dostupen (ni odnoi formuly), i ego vsyacheski mozhno rekomendovat' vsem, vladeyushim angliiskim yazykom i interesuyushimsya sovremennoi astronomiei.
(po angliiski Ultra-Luminous ili Super--Luminous, inogda bez tire) Yarkie rentgenovskie istochniki mogut voznikat' po raznym prichinam. Odin iz klassov takih ob'ektov - eto tesnye dvoinye sistemy, sostoyashie iz kompaktnogo ob'ekta (neitronnoi zvezdy ili chernoi dyry) i normal'noi zvezdy. Veshestvo s normal'nogo komponenta popadaet v pole tyagoteniya kompaktnogo (pri zapolnenii polosti Rosha ili cherez zvezdnyi veter) i, v konce koncov, padaet na ego poverhnost'. Pri etom izluchaetsya bol'shoe kolichestvo energii (gravitacionnoi) v vide zhestkogo rentgenovskogo izlucheniya. Odnako, esli temp akkrecii slishkom velik, to davlenie izlucheniya okazyvaetsya bol'she, chem silya tyagoteniya, i vse veshestvo uzhe ne mozhet upast' na poverhnost' kompaktnogo ob'ekta. Odnovremenno spektr izlucheniya smeshaetsya v myagkuyu oblast', tak kak rentgen pogloshaetsya i pererabatyvaetsya v okruzhayushei kompaktnyi ob'ekt obolochke. Predel'naya svetimost' nazyvaetsya Eddingtonovskoi, ona proporcional'na masse kompaktnogo ob'ekta i dlya 1 Mo ravna 1.3.1038 erg/s. Esli zhe my vidim rentgenovskii istochnik so svetimost'yu poryadka LX=1039-1041 erg/s, to sleduet dumat', chto v etom istochnike nahoditsya sushestvenno bolee massivnyi ob'ekt, chem standartnaya neitronnaya zvezda (s tipichnoi massoi 1.4 Mo). Okonchatel'noi yasnosti s prirodoi sverhizluchayushih istochnikov net, v nashei Galaktike takie ob'ekty neizvestny, no v sosednih oni nablyudayutsya.
Authors: J.M.Miller, G.Fabbiano, M.C.Miller et al.
Commets: 5 pages, 3 color figures, uses emulateapj.sty and apjfonts.sty, ApJL subm
Eta stat'ya osnovana na analize rentgenovskih nablyudenii blizkoi spiral'noi galaktiki NGC 1313 co sputnika XMM-Newton. V etoi galaktike nablyudayutsya dva sverhizluchayushih rentgenovskih istochnika so svetimostyami (pri izotropnom izluchenii) LX = 2.0.1040 erg/s i LX = 6.6.1039 erg/s dlya istochnikov NGC 1313 X-1 i X-2 v diapazone 0.2-10 keV, sootvetstvenno (dlya rascheta svetimosti rasstoyanie do galaktiki schitalos' ravnym 3.7 Mpk). Spektr izlucheniya etih istochnikov sushestvenno bolee myagkii (kT=150 eV), chem u drugih kandidatov v chernye dyry (gde tipichnaya temperatura kT=1 keV). Tak kak izluchenie v takih ob'ektah idet ot akkrecionnogo diska, to polagaya, chto ego vnutrennii krai blizok k poslednei ustoichivoi orbite (t.e. nahoditsya na rasstoyanii 3Rg ot centra chernoi dyry), my poluchaem spektroskopicheskuyu ocenku massy ob'ekta: MBH=100Mo. V etom sluchae ukazannye vyshe znacheniya svetimostei okazyvayutsya blizki k Eddingtonovskim, chto sluzhit eshe odnim podtverzhdeniem takoi ocenki massy.
Authors: Ji-Feng Liu et al
Commets: accepted for ApJ Letter
Chto takoe sverhizluchayushie istochniki - do konca ne yasno (pervoe, chto nado ponyat': izotropno izluchenie ili zhe kollimirovano) . Poetomu lyubaya novaya informaciya o nih predstavlyaet interes. Tak v sverhizluchayushem istochnike ULX M51 X-7 v galaktike M51, rentgenovskaya svetimost' kotorogo menyaetsya v predelah LX=1039-1041 erg/s, po nablyudeniyam c Chandra byl naiden period 2.1 chasa. Avtory predpolagayut, chto etot ob'ekt yavlyaetsya malomassivnoi dvoinoi sistemoi, sostoyashei iz normal'noi zvezdy massoi 0.2-0.3 Mo i kompaktnogo ob'ekta (neitronnoi zvezdy ili chernoi dyry), a 2.1 chasa - ee orbital'nyi period.
Authors: Ji-Feng Liu et al Journal-ref: 2002ApJ...580L..31L
Eshe odin sverhizluchayushii istochnik, ULX NGC 3031 X-11, v galaktike M81 otozhdestvlen v optike (o vazhnosti podobnoi informacii smotri zdes'). Svetimost' etogo istochnika v rentgene sostavlyaet LX~2.1039 erg/s, a v optike na ego meste my vidim massivnuyu moloduyu zvezdu klassa O8V. Vtorym komponentom etoi sistemy, po-vidimomu, yavlyaetsya chernaya dyra s massoi priblizitel'no ravnoi 18 Mo.
Authors: P. Kahabka
Commets: 12 pages, To appear in Compact Stellar X-Ray Sources, eds. W.H.G. and M. van der Klis, Cambridge University Press
Obzor po sverhmyagkim istochnikam. Eto rentgenovskie istochniki s temperaturoi okolo 100 000 - 1 000 000 K, i svetimost'yu 1036-1038 erg/s. Oni byli otkryty v 80-e gg. Eto tesnye dvoinye sistemy, gde akkreciruyushim ob'ektom po vsei vidimosti yavlyayutsya belye karliki. Opisyvayutsya nablyudatel'nye dannye po izvestnym sistemam dannogo tipa, a takzhe rassmatrivayutsya fizicheskie processy, proishodyashie v nih.
Authors: J. Hu, S. N. Zhang, T.P. Li
Commets: 5 page and 3 figure, The 6th pacific rim conference on steller astrophysics -- a tribute to Helmut A. Abt
Rech' idet ob ocenke rasstoyaniya do peremennyh rentgenovskih istochnikov v nashei Galaktike. S rasstoyaniyami v astronomii vsegda bylo trudno. Okazyvaetsya, chto v 1973 g. Tryumper i Shenfel'der predlozhili zabavnyi metod, primenit' kotoryi udalos' tol'ko v 2000 g. Avtory dannoi stat'i nemnozhko modificirovali metodiku. V obshem - dovol'no interesno.
Authors: A. Goldwurm
Commets: 9 pages, including 8 figures, submitted 15 July 2002, to appear in the proceedings of the XXII Moriond Astrophysics Meeting "The Gamma-Ray Universe" (March 9-16, 2002, Les Arcs, France), eds. A. Goldwurm, D. Neumann, and J. Tran Thanh Van, World Publisher (The Gioi), Hanoi (Vietnam)
Daetsya obzor nablyudenii chernyh dyr v dvoinyh sistemah s pomosh'yu sputnikov SIGMA/GRANAT, Compton-GRO, Beppo-SAX i Rossi-XTE. Obsuzhdaetsya, chto smogut uvidet' ot etih ob'ektov takie proekty kak INTEGRAL, SWIFT, AGILE i GLAST.
Authors: Andrew R. King
Commets: 42 pages, 14 figures; to appear in 'Compact Stellar X-Ray Sources', eds. W.H.G. Lewin and M. van der Klis, Cambridge University Press;
Dolgoe vremya imenno nablyudeniya kompaktnyh dvoinyh nashei Galaktiki sostavlyali nablyudatel'nuyu osnovu teorii akkrecii. Eshe sovsem nedavno (neskol'ko let nazad) akkreciya v takih sistemah schitalas' stacionarnoi, a izluchenie ot takih sistem - izotropnym (v pervom priblizhenii). Segodnya my vidim, chto bol'shinstvo rentgenovskih sistem - tranzienty, akkreciruyushee na nih veshestvo vybrasyvaetsya vetrom ili dzhetami, izluchenie ispuskaetsya rezko anizotropno, v diskah sushestvenny proyavleniya razlichnyh neustoichivostei. Krome togo, v sosednih galaktikah obnaruzheny rentgenovskie istochniki, kotoryh prosto net v Mlechnom Puti (v pervuyu ochered' - ultraluminous sources). Pohozhe, chto i zdes' menyaetsya paradigma.
Rekomenduyu prochitat' vsem. No chtenie ne budet legkim, hotya v obzore pochti net formul.
Authors: R.I. Hynes (Texas), D. Steeghs (CfA), J. Casares (IAC), P.A. Charles (Southampton), K. O'Brien (ESO)
Commets: 12 pages; accepted for publication in ApJ Letters
Pohozhe poyavilsya eshe odin kandidat v chernye dyry. Funkciya mass kompaktnogo ob'ekta (t.e. nizhnyaya granica ego massy) prevyshaet 2.0Mo (znachimost' 95%), a po luchshim dannym poluchennym za odin orbital'nyi oborot (okolo 1.7 dnya) -- 5.8+/-0.5Mo.
Authors: Michael J. Stark and Malinda Saia (Lafayette College, Easton, PA)
Commets: 7 pages, 3 figures
Esli my izmeryaem dopplerovskii sdvig linii opticheskoi zvezdy v rentgenovskom istochnike, to my poluchaem nizhnee ogranichenie na massu kompaktnogo ob'ekta. Esli udaetsya izmerit' sdvig rentgenovskih linii, chto gorazdo trudnee, my poluchaem ocenku massy opticheskoi zvezdy, a v kupe s drugimi dannymi mozhem ogranichit' massu kompaktnogo ob'ekta sverhu. Dlya Lebedya X-3 eto udalos' sdelat' - massa kompaktnogo ob'ekta v nem Mx<3.6Mo. Konechno, trebuetsya dopolnitel'naya proverka.
Authors: I. Felix Mirabel, Irapuan Rodrigues
Commets: 4 pages, 1 figure. Animation and high resolution figures can be retrived from the NRAO press release: http://www.aoc.nrao.edu/epo/pr/2003/scox1/
Journal-ref: Astronomy & Astrophysics, 398, L25--L28 (2003)
Rassmatrivatesya vopros o proishozhdenii dvoinoi sistemy Scorpius X-1. Dlya etogo ob'ekta s vysokoi tochnost'yu izvestno rasstoyanie i komponenty skorosti. Poetomu mozhno rassuzhdat', gde on mog rodit'sya. Vvidu netipichnyh dlya diskovyh zvezd parametrov (ekscentrisitet 0.87 i t.d.) delaetsya vyvod, chto naibolee veroyatno, chto dvoinaya sistema byla obrazovana v sharovom skoplenii.
Authors: Dany Vanbeveren
Commets: 21 pages, 6 figures, to appear in "Massive Stars: Formation, Evolution, Internal Structure and Environnement", eds. M. Heydari-Malayeri and J.-P. Zahn
Obsuzhdayutsya razlichnye aspekty evolyucii massivnyh tesnyh dvoinyh sistem.
Sm. takzhe stat'yu "Binary evolution models with rotation"
astro-ph/0302232,
gde vpervye rassmotreny modeli evolyucii s uchetom effektov vrasheniya 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: Rob Fender
Commets: 41-page review. To appear in 'Compact Stellar X-Ray Sources', eds. W.H.G. Lewin and M. van der Klis, Cambridge University Press
Obzor po struinym istecheniyam ot tesnyh dvoinyh sistem s akkreciruyushimi kompaktnymi ob'ektami.
Authors: P. Kaaret, J.J.M. in 't Zand, J. Heise, J.A. Tomsick
Commets: 8 pages, to appear in ApJ
Pri obrabotke dannyh poluchennyh ne sputnike RXTE vo vremya rentgenovskoi vspyshki na ob'ekte SAX J1748.9-2021 v 2001 godu byli obnaruzheny oscillyacii s chastotoi 409.7+/-0.3 Gc. Svetimost' vo vremya vspyshki sostavlyala (3.6+/-0.4) x 1038 erg/s, chto soglasuetsya s eddingtonovskim predelom dlya neitronnoi zvezdy massoi 1.4Mo i radiusom 10 km. Obsuzhdayutsya vozmozhnye prichiny dannyh pul'sacii.
Authors: P.M. Saz Parkinson et al.
Commets: 19 pages, 8 figures, Latex
Rentgenovskii istochnik Cirkul' X-1 (Cir X-1) nablyudaetsya uzhe bolee 30 let. Snachala eto delala Vela 5B, zatem Ariel, Ginga i, nakonec, RXTE. V stat'e obsuzhdaetsya peremennost' etogo istochnika na raznyh vremennyh masshtabah. Na kartine - 30-letnyaya krivaya bleska Ciknbsp;X-1.
Authors: Thomas M. Tauri, Ed van den Heuvel
Commets:46 pages, 17 figures. Review to appear in the book 'Compact Stellar X-Ray Sources', eds. W.H.G. Lewin and M. van der Klis, Cambridge University Press
Glava iz sbornika, posvyashennaya tesnym dvoinym sistemam s akkreciruyushim kompaktnym ob'ektom (neitronnoi zvezdoi ili chernoi dyroi). Rassmatrivayutsya vse osnovnye processy, otvechayushie za evolyuciyu i astrofizicheskie proyavleniya takih sistem.
Authors: Bruce Gendre et al.
Commets: 4 pages, 3 B&W figures. Accepted for publication in A&A Letters
Avtory opisyvayut nablyudeniya slabogo rentgenovskogo istochnika v sharovom skoplenii. Svetimost' istochnika (7-8)1032 erg/s. Avtory polagayut, chto eto tesnaya dvoinaya s neitronnoi zvezdoi v "spokoinom" sostoyanii. Odnako, vozmozhno, chto etot istochnik (kak i nekotorye drugie slabye rentgenovskie istochniki v sharovyh skopleniyah) yavlyaetsya staroi akkreciruyushei odinochnoi neitronnoi zvezdoi (istochnik raspolozhen vblizi centra skopleniya, gde dolzhny byt' naibolee medlennye starye neitronnye zvezdy, i gde plotnost' gaza bol'she). T.o. takaya svetimost' vpolne mozhet ob'yasnyat'sya odinochnoi akkreciruyushei neitronnoi zvezdoi so slabym polem. Ideya o nablyudenii odinochnyh akkreciruyushih neitronnyh zvezd v sharovyh skopleniyah ne nova (sm. astro-ph/0009212 i astro-ph/0102201). Vpolne vozmozhno, chto pervye odinochnye akkreciruyushie neitronnye zvezdy budut identificirovanny imenno v sharovyh skopleniyah.
Authors: Tod E. Strohmayer, Richard F. Mushotzky
Commets: 20 pages, 4 figures, AASTeX. A shortened version has been published in the Astrophysical Journal Letters (2003, 586, L61)
U vnegalakticheskogo ul'tramoshnogo istochnika po dannym HMM-N'yuton otkryty kvaziperiodicheskie oscillyacii na chastote 54 mGc.
Napomnim, chto istochniki nazyvayut ul'tramoshnymi, poskol'ku ih svetimost' (moshnost') prevoshodit Eddingtonovskii predel dlya tipichnoi chernoi dyry s massoi 10 mass Solnca. Mnogie issledovateli polagayut, chto net neobhodimosti pomeshat' v istochnik bolee massivnuyu chernuyu dyru. Vozmozhno, my prosto zavyshaem svetimost', ispol'zuya predpolozhenie o sfericheskoi simmetrii izlucheniya sistemy. Esli zhe est' vydelennye napravleniya (dzhety), chto svetimost' budet men'she, a vidim my yarkii istochnik tol'ko potomu, chto smotrim "v zherlo".
Tak vot avtory polagayut, chto ih dannye (otmetim, chto opyat' zhe dannye HMM-N'yuton i Chandry v nekotorom smysle dopolnyayut drug druga) govoryat o vysokoi svetimosti (poryadka (4 - 5) 1040 erg/s).
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