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15.11.02. astro-ph za 11 - 15 noyabrya 2002 goda: izbrannye stat'i |
S pomosh'yu 300-m radioteleskopa Aresibo i obnovlennogo teleskopa Grin Benk na volne 20 sm byli issledovany 19 sharovyh skoplenii. V nih byli otkryty eshe 7 novyh millisekundnyh radiopul'sarov. 2 iz niz odinochnye, 5 - vhodyat v tesnye dvoinye sistemy. Tri dvoinye sistemy iz pyati obladayut ekscentrichnymi orbitami, a odna iz nih skoree vsego soderzhit relyativistskii kompan'on (belyi karlik ili neitronnuyu zvezdu). Rabota prodolzhaetsya.
Authors: Yoshiaki Taniguchi Commets: 10 pages, 1 figure, Invited Review Paper, To appear in The Proceedings of the IAU 8th Asian-Pacific Regional Meeting Daetsya podrobnyi obzor vozmozhnoi svyazi mezhdu vspyshkami obrazovaniya i AYaG. Posle istoricheskogo vvedeniya avtor podrobno razbiraet korrelyaciyu mezhdu massoi chernoi dyry i massoi baldzha, obnaruzhennuyu na ochen' bol'shom nablyudatel'nom materiale. Avtor polagaet, chto svermassivnye chernye dyry mogli obrazovat'sya v rezul'tate sliyaniya kompaktnyh ob'ektov (neitronnyh zvezd i chernyh dyr), obrazovavshihsya vskore posle moshnoi vspyshki zvezdoobrazovaniya. Zatem obsuzhdaetsya vozmozhnost' obrazovaniya aktivnyh yader (kvazarov) na ochen' bol'shih krasnyh smesheniyah.
Authors: F. Calura, F. Matteucci Comments: 4 pages, 3 figures, to appear in the proceedings of: The Evolution of Galaxies. III: From simple approaches to self-consistent models (Kiel, Germany, July 2002) Korotkaya zametka, v kotoroi avtory rasskazyvayut o svoei rabote po izucheniyu himicheskoi evolyucii galaktik i svyazannyh s etim voprosah. Buduchi napisannoi ochen' yasnym yazykom, zametka mozhet byt' interesna kak nekotoroe vvedenie (na konkretnom primere) v dannuyu oblast'. Odnako, v svyazi s kratkost'yu teksta neobhodimo znanie osnov zvezdnoi astrofiziki i fiziki galaktik.
Authors: P. Cea, L.Tedesco Commets: to appear in Int. Journ. of Mod. Phys. D Avtory utverzhdayut, chto domennye stenki, voznikavshie pri fazovyh perehodah vakuuma na samyh rannih stadiyah evolyucii Vselennoi, obladayut ferromagnitnymi svoistvami. Togda eti stenki mogli porodit' pervichnye zatravochnye magnitnye polya, vazhnye dlya dal'neishih processov evolyucii.
Authors: Davide Lazzati Commets: 12 pages, 2 postscript figures, Review talk at the NBSI workshop "Beaming and Jets in Gamma Ray Bursts", Copenhagen, August 12-30, 2002 Po krainei mere u 5 gamma-vspleskov byli zaregistrirovany rentgenovskie linii izlucheniya, prichem vo vseh etih sluchayah oni imeli shodnye harakteristiki: svetimost' v liniyah sostavlyala L~1044 erg/s, ekvivalentnaya shirina ~1 keV, eto byli linii zheleza (sudya po chastote) i, nakonec, vse oni nablyudalis' primerno cherez 10 chasov posle gamma-vspleska. Linii mogut izluchat'sya v nepodvizhnom veshestve pered frontom udarnoi volny gamma-vspleska ili veshestvom za ee frontom. V oboih sluchayah svetimost' v liniyah pozvolyaet ogranichit' polnuyu svetimost' gamma-vspleska i, takim obrazom, otvetit' na vopros o napravlennosti ili izotropii ego vybrosa. (V dannoi rabote takie ocenki ne sdelany, iz-za nehvatki dannyh, no pokazano kakim putem nado idti.)
(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: Bennett Link Comments: 7 pages, to appear in proceedings of "Radio Pulsars", Chania, Crete, August 2002 (ASP conference series) Odinochnym neitronnym zvezdam mozhet byt' prisusha precessiya. Svyazano eto s napryazheniyami v kore i yadre neitronnoi zvezdy, kotorye privodyat k nesferichnosti zvezdy (prichem, razumeetsya, ob'ekt dolzhen vrashat'sya ne vokrug svoei glavnoi osi). Seichas est' dva kandidata (radiopul'sary), u kotoryh vozmozhno vidyat etot effekt. Nablyudeniya precessii mogut dat' vazhnuyu informaciyu o fizike neitronnyh zvezd. Naprimer, mozhno opredelit' zavisimost' mezhdu tempom zamedleniya pul'sara i uglom mezhdu magnitnoi os'yu i os'yu vrasheniya. Esli precessiruet bystrovrashayushayasya neitronnaya zvezda, to my mozhem rasschityvat' na registraciyu gravitacionnyh voln. V stat'e (kotoraya po suti predstavlyaet soboi miniobzor) daetsya vvedenie, poyasnyayushee chto takoe svobodnaya precessiya, a takzhe kak vyglyadit precessiya pri deistvii zamedlyayushei sily. I, konechno zhe, obsuzhdayutsya precessiruyushie neitronnye zvezdy.
Authors: T.W.B. Kibble Commets: Lectures at NATO ASI "Patterns of symmetry breaking", Cracow, Sept. 2002, 35 pp Narushenie simmetrii pri fazovyh perehoda - ochen' tipichnaya situaciya. Ona vstrechaetsya i v kosmologii, i v "obychnoi" fizike. Esli v odnoi oblasti veshestvo nachinaet perehodit' v "levoe" sostoyanie, a v drugoi, prichinno ne svyazannoi s pervoi, - v "pravoe", to na granice etih oblastei voznikaet tonkii sloi veshestva, kotoroe ne mozhet upast' ni "vlevo", ni "vpravo". V kosmologii takaya struktura nazyvaetsya domennoi stenkoi. A eshe vozmozhny "struny" i "monopoli". Vse eti effekty imeyut svoi analogi v fizike tverdogo tela i mogut byt' vosproizvedeny v laboratorii. V obshem eta stat'ya podoidet tem, kto znaet fiziku tverdogo tela, no ne znaet kosmologii, ili, naoborot, kosmologam, kotorye ishut primery ih drugih razdelov fiziki. Odnako v stat'e dostatochno trudnaya matematika.
Authors: J. Carriere, C.J. Horowitz, J. Piekarewicz Commets: 9 pages and 5 eps. figures (included) Teoriya govorit nam, chto holodnye neitronnye zvezdy mogut imet' massy ot 0.1 massy solnca do 2-3 solnechnyh mass. Nablyudeniya svidetel'stvuyut o tom, chto mozhet sushestvovat' rezkii pik na masse 1.35 mass solnca. Malomassivnuyu neitronnuyu zvezdu ochen' trudno sdelat', t.k. dlya ochen' goryachego ob'ekta minimal'naya massa okazyvaetsya vyshe. I potomu obychnye sposoby obrazovaniya neitronnyh zvezd vryad li dayut ob'ekty s massoi men'she solnechnoi. A zhal'! T.k. eto bylo by po svoemu ochen' interesno. Po-krainei mere tak schitayut avtory stat'i. Delo v tom, chto plotnost' v nedrah obychnyh neitronnyh zvezd prevoshodit yadernuyu v neskol'ko raz. Znachit, izmeriv massu i radius takoi neitronnoi zvezdy, my poluchim vazhnuyu informaciyu o povedenii veshestva pri takih plotnostyah (uravnenie sostoyaniya). No kak byt' s men'shei plotnost'yu? Neitronnye zvezdy tut (poka?) ne pomogut. Zdes', pishut avtory, na pomosh' prihodyat laboratornye izmereniya. Izmereniya radiusa neitrona v yadre svinca dayut informaciyu o povedenii veshestva pri plotnostyah, sootvetstvuyushih nedram neitronnyh zvezd s massami okolo 0.5 mass solnca. T.o. laboratornye i astrofizicheskie dannye mogut dopolnyat' drug druga. Uravnenie sostoyaniya-to v prirode dolzhno byt' odno! Chtoby ego vybrat' nuzhno brat' i dannye po otnositel'no massivnym neitronnym zvezdam, i dannye po svincu.
Authors: Tesla E.Jeltema et al Commets: 28 pages, 7 figures, accepted for publication in ApJ Potok otkrytii, kotorye vydaet rentgenovskaya observatoriya Chandra s pomosh'yu svoego teleskopa s vysokim uglovym razresheniem, stal uzhe obydennym. No vse ravno ot izobrazhenii kosmicheskih ob'ektov v rentgenovskih luchah nevozmozhno otorvat' glaz. Na etot raz nablyudalas' ellipticheskaya galaktika NGC 720. V nei obnaruzheno 42 ranee neizvestnyh tochechnyh rentgenovskih istochnika, vklyuchaya istochnik vblizi ee centra. Bol'shaya chast' etih istochnikov - malomassivnye rentgenovskie dvoinye. 12 iz 42 raspolozheny na rasstoyanii 2" ot kandidatov v sharovye skopleniya v NGC 720. Galaktika ellipticheskaya, a rentgenovskie istochniki v nei pohozhe obrazuyut dugi. Esli vam interesno - dal'she chitaite stat'yu.
Authors: John N. Bahcall Commets: Invited contribution to Hubble History, STScI newsletter Journal-ref: STScI Newsletter, 19, Issue 04, p. 22 (Fall 2002) Mozhet li ser'eznaya nauchnaya programma rodit'sya v kafeterii? Da, esli tam podayut horoshii kofe, a p'yut ego ser'eznye lyudi. A mozhet li ona probit'sya v svet bez problem? Net. V zametke opisan odin iz epizodov noveishei istorii astronomii ego neposredstvennym uchastnikom. Prichem ochen' zhivym yazykom.
Authors: J.L.Han, R.N.Manchester, G.J.Qiao and A.G.Lyne Commets: 4 pages, with good illustrations of B-field structure. To appear in "Radio Pulsars", APS Conf. Ser., editted by M. Bailes, D. Nice, & S. Thorsett Pul'sary ispuskayut sil'no polyarizovannoe radioizluchenie. Prohodya cherez mezhzvezdnuyu plazmu s magnitnym polem ploskost' polyarizacii takogo izlucheniya povorachivaetsya. I eto odin iz samyh moshnyh na segodnyashnii den' instrumentov, pozvolyayushih nam issledovat' magnitnoe pole nashei Galaktiki. Kak vyglyadit struktura magnitnogo polya Galaktiki v ee ploskosti vblizi ot Solnca pokazano na risunke, kotoryi vzyat iz etoi stat'i. Tochki, kruzhki i kvadraty - pul'sary po kotorym stroilas' eta kartina.
Authors: D.Vinkovic, S.Garaj, P.L.Lim et al Commets: 14 pages, 3 figures, Tex; submitted to WGN, the Journal of the IMO To, chto prolet nekotoryh meteorov ili bolidov na dostatochnoi vysote nad Zemlei soprovozhdaetsya shipyashimi zvukami na poverhnosti Zemli, izvestno uzhe bolee 300 let. No do sih por polnogo ob'yasneniya etot effekt (nazyvaemyi elektrofonnym) ne poluchil. Schitaetsya, chto plazmennyi shar, okruzhayushii meteor, izluchaet radiovolny, kotorye, dostigaya poverhnosti Zemli odnovremenno so svetom, sozdayut dostatochno sil'noe peremennoe elektricheskoe pole. Imenno ono i porozhdaet zvuk. No dostatochno ser'eznoi teorii etogo processa net, a krainyaya redkost' "zvuchashih meteorov" ne pozvolyaet ih polnocenno eksperimental'no issledovat'. Proekt Global Electrophonic Fireball Survey (Global'nyi poisk meteorov s elektrofonnym effektom) prednaznachen dlya sbora svidetel'stv ochevidcev. V stat'e obsuzhdaetsya ryad problem (statistika, sistematicheskie oshibki i t.d.), voznikayushih pri podobnom issledovanii.
Authors: Chris Done, Marek Gierlinski Comments: 13 pages, 12 figures, submitted to MNRAS Dokazat', chto my vidim imenno chernuyu dyru ochen' i ochen' neprosto. Osobenno v tesnoi dvoinoi sisteme, gde osnovnaya dolya izlucheniya prihodit ot akkrecionnogo diska. Samye raznye avtory v techenie dolgogo vremeni pytayutsya naiti svoistva, po kotorym mozhno bylo by s uverennost'yu skazat' vidim li my akkreciruyushuyu chernuyu dyru, ili eto vse-taki neitronnaya zvezda. Esli imet' vvidu ochen' vysokii uroven' dostovernosti, to sdelat' eto nevozmozhno. Po toi prostoi prichine, chto v svoih poiskah avtory iznachal'no polagayut, chto takie-to istochniki yavlyayutsya chernymi dyrami, a takie-to neitronnymi zvezdami. A posle ishut zakonomernosti, kotorye potom prilagayut k novym istochnikam. S drugoi storony yasno, chto svoistva dolzhny byt' razlichnymi, tak chto vsya eta nauka nenaprasna. V dannoi stat'e avtory rassmatrivayut evolyuciyu spektrov ob'ektov. Otmechu, chto v stat'e voobshe net formul (tochnee net vydelennyh formul, v tekste-to prostye sootnosheniya vstrechayutsya). Issledovanie provoditsya na bol'shom fatkicheskom materiale. Tak chto chitat' interesno. Avtory polagayut, chto oni nashli sposob "otobrat' chernuyu fasol' ot beloi". No na samom dele, ih rezul'taty pozvolyayut prosto po spektram bez opredeleniya fuekcii mass skazat', chto takoi-to ob'ekt yavlyaetsya kandidatom v chernye dyry. Eto tozhe vazhno, no budem zhdat' bolee pryamyh dokazatel'stv.
Authors: Marc Freitag Commets: 6 pages, 3 figures, accepted for publication in ApJL To, chto v centre nashei Galaktike mozhet byt' chernaya dyra (s nebol'shoi po galakticheskim merkam massoi) predpolagalos' dostatochno davno. Postepenno nakaplivalos' vse bol'she faktov v pol'zu etogo predpolozheniya (sm., naprimer, A.Eckart et al., Nature, 383, 415, (1996)). No samoe ser'eznoe podtverzhdenie etomu faktu poyavilos' sovsem nedavno, kogda byla obnaruzhena pervaya obrashayushayasya vokrug chernoi dyry zvezda. I vot v dannoi stat'e rassmatrivaetsya gravitacionnoe izluchenie ot takih zvezd. Eto ne pervaya rabota na dannuyu temu, no v nei ispol'zuyutsya naibolee tochnye dannye o raspredelenii zvezd vblizi chernoi dyry i o masse poslednei. Kosmicheskii gravitacionnyi interferometr LISA, kotoryi predpolagaetsya zapustit' primerno v 2013-2015 godah, smozhet registrirovat' takoe izluchenie ot zvezd naibolee blizkih k chernoi dyre.
Authors: Konrad Dennerl Commets: 11 pages, 16 figures Journal-ref: A&A 394, 1119-1128 (2002) Solnce svetit v razlichnyh diapazonah elektromagnitnogo spektra, v tom chisle i v rentgenovskom. Planety eto izluchenie otrazhayut (atmosferoi ili poverhnost'yu). Tak chto net nichego udivitel'nogo, chto i ot nih idet rentgenovskoe izluchenie. Naprimer ot Luny ono bylo zaregistrirovano eshe v 1990 godu observatoriei ROSAT. No pomerit' ego ot Marsa do sih por ne udavalos'. Eto smogla sdelat' bole chuvstvitel'naya rentgenovskaya observatoriya Chandra. Kak i predpolagalos', v osnovnom izluchenie idet v flyuorescentnoi linii Kalpha kisloroda.
Authors: M.Turatto, S.Benetti, E.Cappellaro Commets: 10 pages, 4 figues, to appear in Proc. "From Twilight to Highlight - The Physics of Supernovae" ESO/MPA/MPE Workshop Garching July 29 - 31, 2002 V nachale kazhetsya, chto zhenshiny delyatsya na blondinok i bryunetok. Potom zamechaesh', chto est' shatenki i voobshe ottenki. Potom vydelyaesh' krashenyh blondinok, bryunetok, shatenok i t.d. T.e. "ponimanie prihodit s opytom" .... Tak zhe i so sverhnovymi. Do 80-h godov vydelyali dva tipa sverhnovyh. No chem bol'she nablyudali, tem bol'she ponimali, chto etogo nedostatochno. V svoem korotkom obzore avtory rasskazyvayut o mnogoobrazii sverhnovyh. Formul net, est' grafiki, krivye bleska i t.p. Nu i, konechno zhe, ssylki na original'nye raboty.
Authors: S.M.Molnar and M.Birkinshaw Commets: Comments: LateX, 4 pages, 2 figures, accepted for publication in Part 1 of The Astrophysical Journal Kak voobshe mozhno izmerit' skorosti poperechnyh dvizhenii dalekih galaktik? Radial'nye skorosti izmeryayutsya po effektu Dopplera, a s poperechnymi do poslednego vremeni bylo ploho. Peremeshenie galaktiki na nebe (sobstvennoe dvizhenie) zametit' nel'zya - ono ochen' malo. Krome togo galaktika ne tochechnyi ob'ekt i ee smeshenie trudno tochno opredelit'. Poperechnyi effekt dopplera tozhe ne rabotaet, dlya nego nuzhny relyativistskie skorosti. V etoi stat'e predlozheny srazu dva novyh metoda ih izmereniya. (1) Po otnositel'nomu dvizheniyu dvuh sozdannyh linzoi izobrazhenii dalekoi fonovoi galaktiki. (2) Po raznosti krasnyh smeshenii u raznyh izobrazhenii odnogo ob'ekta. Nepodvizhnaya gravitacionnaya linza ne menyaet dlinu volny istochnika, dvizhushayasya - menyaet, prichem eto izmenenie proporcional'no skorosti dvizheniya linzy. Oba metoda opredelyayut poperechnuyu skorost' dvizheniya linzy. Dlya ih illyustracii rassmotreno skoplenie galaktik CL 0024+1654.
Authors: Sylvain Veilleu Commets: 12 pages and 1 jpg-style figure; Invited introductory review, Meudon conference on Active Galactic Nuclei: from Central Engine to Host Galaxy
Szhatyi obzor bez formul, no s bol'shim kolichestvom ssylok (za poslednie 5 let po AYaG opublikovano bolee 5000 statei!!!). Rassmatrivayutsya novye nablyudatel'nye dannye (v osnovnom sputnikovye, i poluchennye v bol'shih obzorah). Obsuzhdayutsya korrelyacii vsego so vsem.
Authors: Paolo Gondolo et al Commets: LaTeX, 6 pages, proceedings of the 4th International Workshop on Identification of Dark Matter (idm2002), York, England, 2-6 September, 2002 Supersimmetrichnye chasticy - naibolee populyarnyi segodnya kandidat na rol' temnoi materii. Paket programm DarkSUSY, napisannyi na yazyke FORTRAN, pozvolyaet provodit' sleduyushie tipy raschetov:
Authors: V.S. Beskin, A.D. Tchekhovskoy Commets: 9 pages, 1 figure, uses sc3conf.sty, to appear in Proc. Third Sakharov Conference on Physics, A.Semikhatov et al. (eds.), Scientific World, Moscow (2003) Otechestvennaya rabota - iz FIANa (doklad na etu temu budet sdelan v konce dekabrya v Moskve na konferencii HEA-2002). Horosho izvestnyi fakt, chto na rasstoyanii 3Rg ot Shvarcshil'dovskoi chernoi dyry dvizhenie probnoi chasticy po krugovoi orbite stanovitsya neustoichivym i ona padaet na chernuyu dyru. S chasticami v akkrecionnom diske, vnutrennii krai kotorogo dohodit do poslednei ustoichivoi orbity, proishodit tozhe samoe - oni padayut vnutr'. No kak pri etom vedet sebya vertikal'naya struktura diska vnutri etoi granicy? Otvet, poluchennyi avtorami pokazan na risunke. Granica ustoichivogo diska raspolozhena sleva, chernaya dyra - sprava.
Authors: M. A. McLaughlin et al. Comments: 5 pages, For Proceedings of the "Radio Pulsars" conference in Crete Korotkaya zametka ob otkrytii novyh radiopul'sarov v skanah, provodimyh na teleskope v Aresibo. Udalos' otkryt' 10 novyh pul'sarov, u dvuh iz nih dovol'no korotkie perioda, no rekordov i sensacii net. Obrabotka dannyh prodolzhaetsya, i avtory nadeyatsya udvoit' chislo novyh ob'ektov.
Authors: D.F. Cowen (for the AMANDA Collaboration) Comments: Invited talk at the XXth International Conference on Neutrino Physics and Astrophysics (Neutrino 2002), Munich, Germany, May 25-30, 2002 Predstavleny novye rezul'taty AMANDY, poluchennye kak na starom, tak i na obnovlennom oborudovanii. Nikakih superotkrytii net. Povyshaetsya statistika, utochnyaetsya fon. Est' predvaritel'nye dannye po poisku istochnikov neitrino sverhvysokih energii (sm. takzhe astro-ph/0211269).
Authors: Steven W. Barwick, for the AMANDA collaboration Commets: 13 pages, 14 figures, Slightly updated from manuscript submitted to SPIE Conference (Hawaii, 2002). Sky plot and preliminary limits given for point sources using AMANDA-II. First report on GRB search using AMANDA-II Teleskop AMANDA registriruet vysokoenergichnye neitrino po cherenkovskomu izlucheniyu porozhdennyh pri stolknovenii s yadrami elektronov i myuonov v antarkticheskom l'du. Pervaya polovina stat'i - kak eto rabotaet i chto sdelano. Nikakih osobenno novyh rezul'tatov tut net. Eta chast' stat'i ochen' napominaet vyshedshuyu dnem ran'she publikaciyu astro-ph/0211264 (predydushii abstrakt). Vtoraya polovina stat'i posvyashena proektu AMANDA-II - planiruemomu uluchsheniyu tekushego varianta ustanovki (ona stanet bol'she po razmeram i luchshe po chuvstvitel'nosti) - i tomu, chto s ee pomosh'yu smogut uvidet'.
Authors: Norbert Christlieb, et al. Commets: Offprint of Nature 419 (2002), 904-906 (issue 31 October 2002) Himicheskii sostav bol'shinstva zvezd s deficitom metallov otrazhaet sostav gaza iz kotorogo oni sformirovalis'. Eti starye zvezdy pozvolyayut ponyat' hod processov zvezdoobrazovaniya i sinteza himicheskih elementov vo Vselennoi. Oni yavlyayutsya lokal'nymi reliktami epoh, kotorye seichas nablyudayutsya na ochen' dalekih krasnyh smesheniyah. Esli budut naideny zvezdy sovershenno ne soderzhashie metallov ("zvezdy populyacii III"), to my smozhem izuchat' veshestvo, rodivsheesya neposredstvenno v Bol'shom Vzryve. Do sih por ne udavalos' naiti zvezdy, v kotoryh by zheleza bylo men'she, chem 10-4 ot Solnechnogo obiliya. V stat'e soobshaetsya ob otkrytii zvezdy v kotoroi zheleza v 200 000 raz men'she, chem v Solnce. Eto eshe ne zvezda populyacii III, no ee otkrytie daet nadezhdu, chto i takie zvezdy mogut byt' otkryty. Eta stat'ya byla opublikovana v zhurnale Nature, 419, 904, (2002). Izlozhenie etoi stat'i mozhno posmotret' na astronet.
Authors: Piergiorgio Picozza and Aldo Morselli Commets: 10 pages, 7 figures, Invited talk at the 18th European Cosmic Ray Symposium, Moscow, July 2002, submitted to Journal of Physics G Esli my budem tochno znat' kolichestvo antichastic (pozitronov, antiprotonov, yader antigeliya) v kosmicheskih luchah, to smozhem otvetit' na celyi ryad voprosov svyazannyh s prirodoi temnogo veshestva i barionnoi asimmetriei Vselennoi. V stat'e rassmotreny rezul'taty eksperimentov vtorogo pokoleniya po poisku antichastic: MASS89, MASS91, TS93, CAPRICE94, CAPRICE98 i poluchennym v nih ogranicheniyam. Vtoraya polovina stat'i posvyashena planiruemomu eksperimentu PAMELLA i sledstviyam ego ozhidaemyh rezul'tatov.
Authors: E. De Donder, Vanbeveren Comments: 18 pages, 6 figures, accepted for New Astronomy Okazyvaetsya, mnogie sovremennye modeli nedouchityvayut vklad samyh massivnyh zvezd v himicheskuyu evolyuciyu Galaktiki. Osobenno ploho vklyuchen v modeli sil'nyi veter, prisushii takim zvezdam. Avtory pytayutsya zapolnit' etot probel, hotya yasno, chto zdes' nuzhny EShE bolee detal'nye issledovaniya (osobenno v tom, chto kasaetsya vzryvov zvezd).
Authors: D. Santos et al. Comments: 6 pages, 3 figures, Proceedings of the 4th International Workshop on the Identification of Dark Matter (York, UK, 09/02/2002-09/06/2002) My uvereny, chto temnoe veshestvo sushestvuet. My uvereny, chto ono nebarionnoi prirody (sm. nizhe, hotya "zerkal'nye bariony" - otdel'naya pesnya: sm. stat'i Blinnikova, Berezhiani i diskussiyu). No my ne znaem, chto zhe eto za chasticy. Mechta - poimat' parochku v zemnoi laboratorii. V stat'e opisyvaetsya proekt takoi ustanovki.
Authors: N.W. Evans Commets: 15 pages, Invited Review for "IDM 2002: The 4th International Workshop on the Identification of Dark Matter ", eds N. Spooner, V. Kudryavtsev (World Scientific) Obsuzhdayutsya: temnoe veshestvo v galo Galaktiki (v pervuyu ochered' barionnoe), mikrolinzirovanie, nu i v svyazi so vsem etim - belye karliki v galo. Lishnii raz mozhno ubedit'sya, chto barionnoe veshestvo ne mozhet ob'yasnit' ves' "temnyi" vklad v galo.
Authors: A. Comastri, P. Ranalli, M. Brusa Comments: 5 pages, 3 colour figures. Proc. workshop "XEUS - studying the evolution of the hot universe", MPE report. LaTeX, xeus.cls included
Pervaya stat'ya posvyashena fonu rentgenovskomu.
On obespechivaetsya v osnovnom vnegalakticheskimi istochnikami.
Seichas sputniki N'yuton i Chandra razreshili znachitel'nuyu chast' fona.
Odnako, gryadut novye proekty. Sredi nih XEUS. Avtory obsuzhdayut, chto novogo
smozhet dat' etot sputnik dlya issledovaniya fona posle raboty Chandry i
N'yutona.
Authors: Herve Dole Comments: Invited Review Talk, 6 pages. To appear in Exploiting the ISO Data Archive - Infrared Astronomy in the Internet Age, 24--27 June 2002, Sig\"uenza, Spain, C. Gry et al. eds., ESA SP-511. Slides of the talk available online at the conference web site: http://www.iso.vilspa.esa.es/meetings/siguenza/schedule.html
Vo vtoroi stat'e rech' idet vo-pervyh ob IK diapazone. A vo-vtoryh o
sputnike, kotoryi uzhe dal rezul'taty -
ISO.
Sputnik rabotal v 1995-98 godah. Eto byl 60-santimetrovyi teleskop,
nablyudavshii v diapazone ot 2.5 do 240 mikron. Sredi mnozhestva ego
rezul'tatov - glubokie nablyudeniya, pozvolivshie razreshit' fon na istochniki.
Eto, kak i v rentgene, v osnovnom vnegalakticheskie ob'ekty.
Takie dannye kraine vazhny dlya ponimaniya processov, opredelyayushih evolyuciyu
galaktik.
Authors: Avishay Gal-Yam et al. Commets: 25 pages, 2 figures, To appear in AJ, Feb. 2003 issue V rezul'tate vypolneniya programmy poiska sverhnovyh obnaruzheny 7 sverhnovyh tipa Ia v skopleniyah galaktik na z ot 0.06 do 0.2, ne prinadlezhashie ni k odnoi iz galaktik skopleniya. Veroyatno eti zvezdy ne byli vybrosheny iz galaktik, a rodilis' iz diffuznogo gaza, zapolnyayushego mezhgalakticheskoe prostranstvo. Avtory predpolagayut, chto okolo 20% sverhnovyh v skopleniyah galaktik mogut okazat'sya mezhgalakticheskimi.
Authors: Joseph Samuel Commets: four pages, submitted to PRL OTO predskazyvaet, chto front ploskoi elektromagnitnoi volny budet iskrivlyat'sya iz-za gravitacionnyh effektov. Dlya tel v Solnechnoi sisteme etot effekt sostavlyaet sekundy i do sih por ne byl zafiksirovan. Odnako, poslednie dostizheniya v tehnike interferometrii so sverhdlinnoi bazoi (VLBI) delayut ego izmerenie vozmozhnym. Avtory opisyvayut podobnyi eksperiment, kotoryi vozmozhno provesti s ispol'zovaniem raspolozhennyh v raznyh tochkah Zemli VLBI-stancii.
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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