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Novosti nauki
The R.A.P. Project
19.01.10. astro-ph za 10 - 17 yanvarya 2002 goda: izbrannye stat'i





Stat'i nedeli
"Luchshie iz luchshih".

  • astro-ph/0301243 Massa neitronnoi zvezdy v Vela X-1 (The mass of the neutron star in Vela X-1 and tidally induced non-radial oscillations in GP Vel)
    Authors:H. Quaintrell et al.

  • astro-ph/0301263 Uskorenie chastic putem mnogokratnogo perehoda iz zaryazhennogo sostoyaniya v neitral'noe i obratno (Particle Acceleration through Multiple Conversions from Charged into Neutral State and Back)
    Authors: E.V. Derishev et al.

  • astro-ph/0301282 LSR0602+3910 - samyi yarkii korichnevyi karlik? (LSR0602+3910 - The Brightest Brown Dwarf in the Sky?)
    Authors: Samir Salim et al.

  • gr-qc/0212121 Postn'yutonovskaya interpretaciya VLBI eksperimenta 8 sentyabrya 2002 goda
    Authors: S.M.Kopeikin

  • astro-ph/0301328 Stroboskopicheskie opticheskie nablyudeniya pul'sara v Krabe (Stroboscopic optical observations of the Crab pulsar)
    Authors: Simon Vidrih et al.


    sputnik astro-ph/0301158 Sputnik MAP - Microwave Anisotropy Probe (The Microwave Anisotropy Probe (MAP) Mission)
    Authors: C. L. Bennett et al.
    Commets: ApJ in press; 22 pages with 10 low-resolution figures; version with better quality figures is available at http://map.gsfc.nasa.gov/m_mm/tp_links.html

    Seriya statei pro sputnik MAP (astro-ph/0301159, astro-ph/0301160, astro-ph/0301164).

    Opisyvayutsya razlichnye detali ustroistva sputnika, ego naznachenie i t.d. i t.p. Naibolee obshaya i dostupnaya stat'ya - astro-ph/0301158. V svyazi so skorym opublikovaniem pervyh dannyh s etogo sputnika stat'ya budet nebezinteresna vsem interesuyushimsya sovremennoi kosmologiei.


    astro-ph/0301161 Rentgenovskaya spektroskopiya odinochnoi neitronnoi zvezdy 1E1207.4-5209: sostav atmosfery i uravnenie sostoyaniya (X-ray spectroscopy of the isolated neutron star 1E1207.4-5209: Atmospheric composition and equation of state)
    Authors: Kaya Mori, Charles J. Hailey
    Commets: 26 pages, 8 figures, submitted to ApJ

    U neitronnoi zvezdy 1E1207.4-5209 po dannym Chandry obnaruzheno dve shirokie spektral'nye detali. Avtory stat'i dayut interpretaciyu etim nablyudeniyam. Po ih raschetam za detali otvetstvenny geliepodobnye atomy kisloroda v magnitnom pole 1012 Gs (tipichnom dlya neitronnyh zvezd). Esli schitat', chto massa neitronnoi zvezdy primerno 1.4 massy Solnca, to mozhno sdelat' ogranicheniya na uravneniya sostoyaniya: ono okazyvaetsya dostatochno zhestkim.


    astro-ph/0301162 Yarkie sverhmyagkie rentgenovskie istochniki vo vneshnih galaktikah (Luminous Supersoft X-Ray Sources in External Galaxies)
    Authors: R. Di Stefano and A.K.H. Kong (CfA)
    Commets: 14 pages, 6 figures, ApJ submitted

    Kolichestvo sverhmyagkih rentgenovskih istochnikov so svetimost'yu L > 1037 erg/s v sosednih galaktikah sostavlyaet po krainei mere neskol'ko soten, no mozhet byt' i sushestvenno bol'she. Krome togo:

    1. sredi istochnikov est' gruppa so svetimostyami L > 1037 erg/s;
    2. v spiral'nyh galaktikah M101, M83 i M51 sverhmyagkie istochniki associiruyutsya u spiral'nyh vetvei, chto ukazyvaet na ih nebol'shoi (<108 let) vozrast.


    astro-ph/0301174 Sboi pul'sara v Krabe: individual'nye sobytiya i kumulyativnyi effekt (The Crab glitches: incidence and cumulative effect)
    Authors: F.Graham Smith, C. Jordan
    Commets: 6 pages 5 figures, to appear in "Radio Pulsars" (ASP Conf. Ser.), eds. M. Bailes, D. Nice, & S. Thorsett

    Za 33 goda nablyudenii pul'sara v Krabe nablyudalos' 14 glitchei (sboev perioda vrasheniya), za kotorymi shli periody relaksacii. No vse eti sboi mozhno predstavit' kak 3 "gigantskih" sobytiya razdelennyh primerno 12 godami. Takaya gipoteza pozvolyaet snyat' nekotorye problemy s zakonami tormozheniya.


    astro-ph/0301184 The phase coherence of light from extragalactic sources - direct evidence against first order quantum gravity fluctuations in time and space
    Authors: Richard Lieu, Lloyd W. Hillman
    Commets: 9 pages, Accepted for publication by the Astrophysical Journal Letters

    Vse bolee-menee uvereny, chto na ochen' malen'kih masshtabah (poryadka plankovskogo) svoistva prostranstva-vremeni dolzhny byt' otlichny ot privychnyh nam. Odnako, net nikakih eksperimental'nyh dannyh na etot schet (krome dovol'no plohih verhnih predelov). V stat'e rassmatrivaetsya, kak mozhno takie dannye poluchit' i kakie predely dayut sovremennye nablyudeniya. Avtory predlagayut ispol'zovat' nablyudeniya fazovoi kogerentnosti izlucheniya ot vnegalakticheskih istochnikov dlya polucheniya sootvetstvuyushei informacii (otmetim, chto vnegalakticheskie nablyudeniya v gamma-diapazone uzhe aktivno ispol'zuyutsya dlya poiska masshtaba kvantovoi gravitacii, no poka - predely, predely, predely...). V kachestve illyustracii rassmatrivayutsya nablyudeniya kolec Eiri ot odnoi aktivnoi galaktiki. Razumeetsya, opyat'-taki poka prosto mozhno dat' nekotorye verhnie predely, no metodika interesnaya.


    miniobzor astro-ph/0301186 Laiman-al'fa les kak kosmologicheskii instrument (The Lyman-alpha Forest as a Cosmological Tool)
    Authors: David H. Weinberg, Romeel Dav'e, Neal Katz, Juna A. Kollmeier
    Commets: 13 pages, to appear in "The Emergence of Cosmic Structure," Proceedings of the 13th Annual Astrophysics Conference in Maryland, eds. S. Holt and C. Reynolds, AIP Press, 2003

    Laiman-al'fa les - eto nabor spektral'nyh linii (pogloshenie) v spektre dalekogo vnegalakticheskogo ob'ekta, poyavlyayushiisya za schet veshestva na luche zreniya. Kvazar (ili galaktika) "prosvechivaet" vselennuyu, i my mozhem poluchat' vazhnuyu informaciyu o raspredelenii veshestva, kotorye drugimi metodami chasto neobnaruzhimo. V stat'e opisyvaetsya dannyi metod kosmologicheskih issledovanii. Avtory privodyat bol'shoi (dlya korotkogo obzora) spisok literatury. Tak chto zhelayushie mogut prodolzhit' chtenie, ispol'zuya uzhe original'nye stat'i.


    obzor astro-ph/0301196 Astrofizika kosmicheskih luchei i vzaimodeistvie adronov (Cosmic Ray Astrophysics and Hadronic Interactions)
    Authors: Paolo Lipari
    Commets: Summary talk at the XII ISVHECRI (Inernational Symposium on Very High Energy Cosmic Ray Interactions). 16 pages, 9 figures

    Istoriya izucheniya kosmicheskih luchei dlitsya uzhe vek, pri etom nekotorye ochen' vazhnye voprosy ne imeyut otvetov. Perspektivy blizhaishego desyatiletiya vpechatlyayut. Krome sovremennyh i planiruemyh eksperimentov v obzore rassmatrivaetsya vklad v astrofiziku kosmicheskih luchei, kotoryi mogut dat' pryamye izmereniya na uskoritele LHC v Cerne.


    astro-ph/0301197 Izmenenie rasstoyaniya mezhdu izobrazheniyami v gravitacionnoi linze PKS 1830-211 (Changes in the measured image separation of the gravitational lens system, PKS 1830-211)
    Authors: C.Jin, M.A. Garrett, S. Nair, R.W. Porcas, A.R. Patnaik, R. Nan
    Commets: 8 pages, 5 figures

    V techenie 14 nedel' s pomosh'yu VLBA na chastote 43 GGc stroilis' karty gravitacionnoi linzy PKS 1830-211. Za eto vremya rasstoyanie mezhdu centrami izobrazhenii izmenilos' na 87 mikro uglovyh sekundy.


    miniobzor astro-ph/0301199 Vremya ot nachala (Time Since the Beginning)
    Author: Alan H. Guth
    Commets: 13 pages, including 4 figures, LaTeX 2.09, attached style file AATS2.sty required. Review talk given at "Astrophysical Ages and Time Scales," Hilo, Hawaii, 5-9 February 2001. The paper has already been published
    Journal-ref: Astrophysical Ages and Time Scales," Astronomical Society of the Pacific Conference Series, vol. 245, pp. 3-17 (2001)

    Odin iz osnovopolozhnikov teorii inflyacii dovol'no populyarno pishet o svoei tematike. V principe nichego novogo, no pochitat' priyatno. Krome togo, postroeny nekotorye prostye grafiki, kotorye polezno imet' pered glazami, razmyshlyaya o raznyh modelyah.


    astro-ph/0301229 Obnaruzhenie temnoi materii s pomosh'yu centrifugi (Detecting dark matter using centrifuging techniques)
    Authors: S. Mitra and R. Foot
    Commets: About 9 pages

    Avtory obrashayut vnimanie na to, chto poka nedostatochno proverena odna iz gipotez. Ona zaklyuchaetsya v tom, chto krome togo, chto chasticy temnoi materii mogut dostatochno sil'no vzaimodeistvovat' drug s drugom, chtoby obrazovyvat' "granuly" (grains), oni mogut dostatochno sil'no vzaimodeistvovat' s obychnym veshestvom, chtoby nahodit'sya vokrug nas. Takie chasticy poluchayutsya v nekotoryh teoriyah s t.n. "zerkal'noi simmetriei". Po mneniyu avtorov obnaruzhit' takie chasticy (tochnee granuly) mozhno s pomosh'yu centrifugi, ispol'zuya obychnoe veshestvo v kachestve fil'tra. Sovremennye centrifugi mogut davat' uskorenie do 106 g. Pri upomyanutoi vyshe sile svyazi granuly iz chastic temnoi materii prosto "vyletyat" iz issleduemogo obrazca pri rabote centrifugi, esli ih razmer bol'she 100 mikron. Sootvetstvenno massa umen'shitsya, chto mozhno budet zaregistrirovat'. Po mneniyu Mitry i Futa etogo mozhet byt' dostatochno dlya obnaruzheniya chastic, esli oni sostavlyayut bolee millionoi doli (po masse) v issleduemom obrazce (otricatel'nyi rezul'tat eksperimenta pozvolit nalozhit' vazhnye verhnie predely na parametry chastic temnoi materii, v chastnosti mozhet pokazat', chto svyaz' dolzhna byt' slabee 10 -10 ot obychnoi kulonovskoi ).


    astro-ph/0301232 Rentgenovskie AGN na ochen' vysokih krasnyh smesheniyah v severnom glubokom pole Chandra (Very High Redshift X-ray Selected AGN in the Chandra Deep Field-North)
    Authors: A.J.Barger et al.
    Commets: 5 pages, accepted by The Astrophysical Journal Letters

    Pohozhe, chto Chandra pozvolyaet obnaruzhivat' aktivnye yadra galaktik na vysokih krasnyh smesheniyah po ih rentgenovskomu izlucheniyu, dazhe esli opticheskaya svetimost' nizka. Iz 423 dostatochno yarkih rentgenovskih istochnikov bol'shinstvo okazalis' lezhashimi v intervale z=5-6, a nekotorye na z>6 (z opredelyalos' po sravneniyu potokov v sosednih rentgenovskih intervalah). Iz etih istochnikov tol'ko primerno polovina vidna v optike.


    astro-ph/0301238 Spektroskopiya vysokogo razresheniya zheltogo sverhgiganta Rho Kassiopei s 1993 vklyuchaya vspyshku 2000-2001 goda (High-Resolution Spectroscopy of the Yellow Hypergiant Rho Cassiopeiae from 1993 Through the Outburst of 2000-2001)
    Authors: A.Lobel et al.
    Commets: 86 pages, 15 figures, ApJ accepted for 2003, Feb. 1 issue. Press release, illustrations, and movies are available at http://cfa-www.harvard.edu/~alobel

    V 2000-2001 godu na zheltom sverhgigante proizoshla vspyshka, podobnaya nablyudavsheisya v 1945-47 i 1985-86 godah, no izuchenie ee bylo provedeno sovremennymi metodami. Vo vspyshke klass zvezdy izmenilsya ot A do M. Temp poteri massy dostig Mdot ~= 5.4h10-2Mo/god. Pohozhe eto eshe odna zvezda tipa, Ets Kariny, kotoraya zavershila svoyu Yadernuyu evolyuciyu i v blizhaishee vremya vzorvetsya kak Sverhnovaya (pod blizhaishim vremenem podrazumevayutsya neskol'ko soten tysyach let).


    astro-ph/0301239 Novyi podhod k morfologii galaktik: analiz pervogo reliza Sloanovskogo cifrovogo obzora neba ( A New Approach to Galaxy Morphology: I. Analysis of the Sloan Digital Sky Survey Early Data Release)
    Authors: Roberto Abraham et al.
    Commets: ApJ in press

    Seichas v astronomii nachinayut dominirovat' proekty, v kotoryh poluchaetsya ogromnoe kolichestvo dostatochno odnorodnoi informacii (avtomatizirovanye obzory neba i dr.). Potomu voznikaet neobhodimost' v novyh metodah obrabotki dannyh (vspomnim, naprimer, pro primenenie neironnyh setei (Belokurov i dr. 2002)). V etoi stat'e avtory opisyvayut novyi podhod k opredeleniyu morfologii galaktik. Krome astronomov sootvetstvuyushih special'nostei stat'ya mozhet byt' interesna specialistam po obrabotke dannyh.


    astro-ph/0301240 Razdelenie fotonov i adronov po fluktuaciyam Cherenkovskogo izlucheniya (Gamma-Hadron Separation using Cerenkov Photon Density Fluctuations)
    Authors: V.R.Chitnis, P.N.Bhat
    Commets: 26 pages, 9 ps figures, 1 eps figure, To appear in Experimental Astronomy

    Cherenkovskie teleskopy registriruyut kak fotony sverhvysokih energii, tak i zaryazhennye chasticy (adrony). Obychno ih razdelyayut po forme poluchayushegosya izobrazheniya. No eto vozmozhno tol'ko v teleskopah stroyashih izobrazhenie. V stat'e predlozhen metod vydeleniya adronnyh sobytii po fluktuaciyam Cherenkovskogo izlucheniya. Eta stat'ya mozhet byt' interesna ne tol'ko astronomam.


    astro-ph/0301243 Massa neitronnoi zvezdy v Vela X-1 (The mass of the neutron star in Vela X-1 and tidally induced non-radial oscillations in GP Vel)
    Authors: H. Quaintrell et al.
    Commets: Accepted for publication in Astronomy & Astrophysics, 12 pages

    Opredelenie mass neitronnyh zvezd - ochen' vazhnaya zadacha, t.k. ona napryamuyu svyazana s fizikoi povedeniya veshestva pri ekstremal'nyh plotnostyah. Poka horosho opredeleny massy u neskol'kih radiopul'sarov. Voobshe, massy v astronomii proshe opredelyat' v dvoinyh sistemah. Poetomu, krome dvoinyh radiopul'sarov, bol'shoe vnimanie privlekayut rentgenovskie pul'sary. Ih izvestno neskol'ko desyatkov. No v formulu dlya opredeleniya massy vhodyat parametry orientacii orbity, kotorye obychno neizvestny. Krome sluchaev zatmennyh sistem. Nalichie zatmenii oznachaet, chto my nahodimsya pochti p ploskosti orbity. Dlya takih sistem, esli est' dannye po spektroskopii normal'noi zvezdy, mozhno dovol'no tochno opredelit' massu neitronnoi. Izvestno 7 rentgenovskih pul'sarov s zatmeniyami. Vela X-1 - odin iz nih.

    Dolgoe vremya massa neitronnoi zvezdy v Vela X-1 byla samoi vysokoi (1.9 mass Solnca, Barziv i dr. 2001) i potomu s etim rezul'tatom sporili. I vot nezavisimaya gruppa podtverzhdaet vysokuyu massu neitronnoi zvezdy! Uchityvaya vse neopredelennosti massa sostavlyaet ot 1. 75 massy Solnca do 2. 44.

    O drugih, menee tochnyh, sposobah ocenki massy i ogranicheniyah na uravnenie sostoyaniya sm. svezhuyu rabotu "X-ray Studies of Two Neutron Stars in 47 Tucanae: Toward Constraints on the Equation of State" astro-ph/0301235 i vyshe astro-ph/0301161. Proizvedeny, takzhe, izmereniya v sisteme J1740-5340, gde millimekundnyi pul'sar isparyaet malomassivnogo soseda (astro-ph/0301244). Polucheno horoshee znacheniya dlya otnosheniya mass komponentov, no sami massy oceneny s bol'shoi oshibkoi.


    obzor astro-ph/0301248 Obrazovanie i evolyuciya ellipticheskih galaktik (Formation and Cosmic Evolution of Elliptical Galaxies)
    Authors: J.A. de Freitas Pacheco et al.
    Commets: 59 pages, 9 figures, Recent Research Developments in Astronomy and Astrophysics, in press, ps and pdf versions with higher resolution figures are also available at: http://www.obs-nice.fr/peirani/elliptical.html

    Bol'shoi obzor po ellipticheskim galaktikam. Dannaya tema imeet otnoshenie kak (estestvenno) k fizike galaktik, tak i k zvezdnoi kinematike, kosmologii (obrazovanie struktur vo Vselennoi), astrofizike sverhmassivnyh chernyh dyr i t.d. Avtory privodyat mnogo fakticheskih dannyh.


    astro-ph/0301250 Tomografiya akkrecionnyh potokov vblizi chernyh dyr (Echo Tomography of Black Hole Accretion Flows)
    Authors: Keith Horne
    Commets: To appear in: Astronomical Telescopes and Instrumentation, Future EUV, UV, and Visible Space Astrophysics Missions and Instrumentation, 22-28 Aug 2002, Waikoloa, HI, SPIE Proc 4856

    Keit Horn (Keith Horne) yavlyaetsya izvestnym specialistom po tomografii akkrecionnyh diskov. Takoi vid issledovaniya vozmozhen, naprimer, v zatmennyh dvoinyh sistemah. V etoi stat'e rech' idet ob issledovanie akkrecionnyh potokov v aktivnyh yadrah galaktik, gde vtorogo ob'ekta net! Zdes' tehnologiya sovsem drugaya. Issleduetsya "eho" - pereizluchennyi svet. Izmeryayutsya vremennye zaderzhki, doplerovskii sdvig i t.d. Poka metodika nahoditsya v stadii stanovleniya. Avtor nadeetsya, chto v skorom budushem ona pomozhet uznat' mnogo novogo o processah v aktivnyh yadrah galaktik.


    astro-ph/0301252 Evolyuciya rezonansnyh par planet (Evolution of Migrating Planet Pairs in Resonance)
    Authors: S.Ferraz-Mello, C.Beauge and T.A.Michtchenko
    Commets: submitted to Celestial Mechanics and Dynamical Astronomy

    V rabote dano chislennoe modelirovanie evolyucii pary planet (ili massivnyh sputnikov) nahodyashihsya v rezonanse 2/1 ili 3/1, pod vozdeistviem prilivnyh sil (bez dissipacii).


    astro-ph/0301257 Odinochnye i dvoinye chernye dyry i ih vliyanie na strukturu yader (Single and Binary Black Holes and their Influence on Nuclear Structure)
    Authors: David Merritt
    Commets: 10 pages, 4 figures

    Na strukturu raspredeleniya zvezd vblizi centra galaktiki ochen' sil'no vliyaet Raspolozhennaya v centre chernaya dyra. Avtor delaet vyvod, chto v yadrah galaktik S absolyutnoi vidimoi velichinoi Mv>-20 ob'yasnyayutsya odinochnymi chernymi dyrami, a v bolee yarkih - chernye dyre dvoinye.


    miniobzor astro-ph/0301259 Evolyuciya massivnyh zvezd s vrasheniem i poterei massy (Evolution of massive stars with rotation and mass loss)
    Author: Andre Maeder, Georges Meynet
    Commets: 10 pages, 13 figures, IAU Symp. 215 `Stellar Rotation'', A. Maeder and P. Eenens eds., ASP Conf Ser. in press

    Lidery zhenevskoi gruppy po izucheniyu zvezdnoi evolyucii dayut korotkii obzor vliyaniya effektov vrasheniya na zhiznennyi put' massivnyh zvezd. Oni okazyvayutsya dovol'no sushestvennymi. Prichem, chem nizhe metallichnost', tem vazhnee vrashenie. Eto okazyvaetsya vazhnym seichas v svyazi s vozrosshim interesom k zvezdam PopIII - samym pervym zvezdam, kotorye voznikli iz veshestva, pochti svobodnogo ot tyazhelyh elementov, a zatem, vzorvavshis' kak sverhnovye, obogatili nash mir elementami ot ugleroda do zheleza (i dal'she do urana).

    Sm. takzhe stat'yu "The effects of rotation on Wolf--Rayet stars and on the production of primary nitrogen by intermediate mass stars" astro-ph/0301287.


    astro-ph/0301263 Uskorenie chastic putem mnogokratnogo perehoda iz zaryazhennogo sostoyaniya v neitral'noe i obratno (Particle Acceleration through Multiple Conversions from Charged into Neutral State and Back)
    Authors: E.V. Derishev et al.
    Commets: 18 pages, submitted to Phys. Rev. D

    Avtory predlagayut novyi metod uskoreniya kosmicheskih luchei. Osnovnaya ideya sostoit v tom, chto chasticy mogut ispytyvat' mnogokratnye perehody i zaryazhennogo sostoyaniya v neitral'noe i obratno (naprimer: proton<->neitron, elektron/pozitron<->foton).

    Dannyi metod pozvolyaet uskoryat' chasticy do 1020 eV i vyshe, esli rech' idet o gamma-vspleskah i aktivnyh yadrah galaktik. Na men'shem masshtabe metod rabotaet v mikrokvazarah.

    "Pobochnym effektom" dannogo processa yavlyaetsya izluchenie elektromagnitnyh voln i neitrino. Po mneniyu avtorov imenno eto yavlenie mozhet byt' otvetstvenno za gamma-izluchenie kosmicheskih vspleskov (dannyi vopros takzhe rassmatrivaetsya B. Shternom).


    astro-ph/0301265 Novoe ob'yasnenie krivyh vrasheniya v spiral'nyh galaktikah bez galo temnoi materii s pomosh'yu akkrecii mezhgalakticheskogo veshestva (A new hypothesis to explain rotation curves in spiral galaxies without dark matter haloes by means of the accretion of the intergalactic medium)
    Authors: M. Lopez-Corredoira
    Commets: 25 pages, 6 figures, submitted to RevMexAA

    Medlennoe ubyvanie skorosti vrasheniya vneshnih chastei galaktik (tak nazyvaemye "ploskie krivye vrasheniya") do sih por ob'yasnyalis' libo nalichiem nevidimogo galo, libo modificirovannym zakonom gravitacii. V dannoi stat'e predlozheno eshe odno ob'yasnenie - akkreciya mezhgalakticheskogo veshestva. Eta zhe gipoteza ob'yasnyaet U-obraznoe iskrivlenie ploskosti diska nekotoryh galaktik.