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Novosti nauki
The R.A.P. Project
05.07.02. astro-ph za 1-5 iyulya 2002 goda: izbrannye stat'i


astro-ph/0207001 A High-Energy Study of the Geminga Pulsar
Authors: M. S. Jackson et al.
Comments: 22 pages including 7 figures

Neitronnye zvezdy byvayut samymi raznymi: eto i radiopul'sary; i anomal'nye rentgenovskie pul'sary; i radiotihie neitronnye zvezdy i t.d. i t.p. (sm. obzor na russkom yazyke v astro-ph/0205298).

Sredi vsego etogo zooparka osoboe mesto zanimaet Geminga. Po vsei vidimosti eto molodaya odinochnaya neitronnaya zvezda, yavlyayushayasya radiopul'sarom, no radio luch ne prohodit cherez zemnogo nablyudatelya (isklyucheniem yavlyaetsya nizkochastotnaya oblast', gde Geminga byla zaregistrirovana Pushinskimi astronomami).

V dannoi stat'e avtory privodyat rezul'taty glubokih nablyudenii Gemingi v zhestkom diapazone na sputnikah ASCA , RXTE i CGRO.

V rabote obsuzhdaetsya povedenie neitronnoi zvezdy posle glitcha, t.e. sboya perioda vrasheniya. Rezul'taty interpretiruyutsya v modeli vneshnego zazora (outer-gap). Obsuzhdayutsya dal'neishie nablyudeniya.

astro-ph/0207003 RXTE Observations of 3C273 between 1996 and 2000:Variability Timescale and Jet Power
Authors: Jun Kataoka et al.
Comments: 13 pages, 8 figures, accepted for publication in MNRAS

"... a takzhe hlebnee kvazara."
Kvazar, kak mnogo v etom zvuke.... (c)

Po-prezhnemu kvazary i drugie aktivnye yadra galaktik privlekayut bol'shoi interes nablyudatelei i teoretikov.

Gruppa yaponskih astronomov predstavlyaet rezul'taty dlitel'nogo monitoringa samogo blizkogo i izvestnogo kvazara 3C273. Polnoe vremya ekspozicii na sputnike RXTE sostavilo 845 kilosekund.

Avtory obsuzhdayut peremennost' kvazara, a takzhe ego spektral'nye harakteristiki.

astro-ph/0207006 The Microlensing Event MACHO-99-BLG-22/OGLE-1999-BUL-32: An Intermediate Mass Black Hole, or a Lens in the Bulge
Authors: D.P. Bennett et al.
Comments: 11 pages with 2 color Figures

K "goryachim" temam bezuslovno otnosyatsya mikrolinzy. Metod mikrolinzirovaniya pozvolyaet "uvidet' nevidimoe", mozhno opredelyat' parametry temnyh ob'ektov, esli oni vystupayut v roli gravitacionnyh linz (sm. obzor v stat'e Zaharova i Sazhina v UFN 1998).

Chem dol'she prodolzhitel'nost' epizoda linzirovaniya tem bol'she (pri prochih ravnyh parametrah) massa linzy. Esli eto temnyi massivnyi ob'ekt, to eto chernaya dyra! Avtory stat'i obsuzhdayut samyi dlitel'nyi sluchai mikrolinzirovaniya MACHO-99-BLG-22/OGLE-1999-BUL-32. V rezul'tate predpolagaetsya, chto ob'ekt mozhet byt' chernoi dyroi s massoi 100 mass Solnca!!!!! Eto udivitel'no, t.k. zvezdnye chernye dyry obychno imeyut massy poryadka 10 mass Solnca (sm., naprimer, obzor Cherepashuka v UFN 1996).

Odnako, est' eshe odna vozmozhnost'. Esli linza nahoditsya daleko, to ee massa mozhet byt' men'she. V takom sluchae, polagayut avtory raboty, linza mozhet byt' obychnoi chernoi dyroi ili neitronnoi zvezdoi v baldzhe Galaktiki.

astro-ph/0207025 The Point-Agape survey: No Need for Machos in M31 ?
Authors: S. Paulin-Henriksson et al. (The POINT-AGAPE Collaboration)

I snova mikrolinzy. Na etot raz nablyudeniya Tumannosti Andromedy (M31). S pomosh'yu drugoi tehniki (piksel'noe mikrolinzirovanie, v etom sluchae zvezdy ne razreshayutsya, a nablyudatel' vidit tol'ko povyshenie potoka v odnom iz elementov matricy) issleduetsya galo blizhaishei krupnoi galaktiki.

Rezul'tatom raboty yavlyaetsya nablyudenie 4 sluchaev linzirovaniya. Odin iz chetyreh epizodov svyazan so zvezdoi v baldzhe M31, tri drugih mozhno ob'yasnyat' kak zvezdami, tak i massivnymi kompaktnymi ob'ektami galo (MACHO). Na osnovanii etogo avtory delayut neozhidannyi vyvod, chto ih vyborka ne trebuet prisutstviya MACHO.

obzor! astro-ph/0207032 Strong and weak lensing by galaxy clusters
Author: Matthias Bartelmann
Comments: 7 pages, no figures

Korotkii, no ponyatnyi obzor po problemam linzirovaniya na skopleniyah galaktik. Takzhe perechislyayutsya osnovnye rezul'taty, poluchennye dannym metodom.

astro-ph/0207034 Searching for low mass objects around nearby dMe radio stars
Authors: J.C. Guirado et al.
Comments: 4 pages, 3 figures

"Goryachaya" tema: ekzoplanety. Po mneniyu avtorov stat'i blizkie M-karliki ideal'nye ob'ekty dlya poiska malomassivnyh kompan'onov, t.e. planet. Poisk predpolagaetsya vesti v radio diapazone s pomosh'yu sistemy VLBI (Very Large Base Interferometer).

Tochnost' nablyudenii pozvolyaet "uvidet'" planetu s massoi Yupitera. V dannoi rabote avtory predstavlyayut pervye rezul'taty svoih nablyudenii.

astro-ph/0207044 The Formation of a Realistic Disk Galaxy in Lambda Dominated Cosmologies
Authors: F. Governato et al.
Comments: submitted to ApJL. Images and movies at http://hpcc.astro.washington.edu/faculty/fabio/galform.html

Vpervye provedeno modelirovanie obrazovaniya realistichnoi galaktiki, ch'ya struktura opredelyaetsya diskom. Izucheny svoistva obrazovavshegosya ob'ekta vplot' do nashego vremeni.

Model' vklyuchaet v sebya ohlazhdenie, zvezdoobrazovanie, vspyshki sverhnovyh i UF fon. Disk pri obrazovanii okazyvaetsya holodnym (v dinamicheskom smysle), no zatem "nagrevaetsya" za schet neustoichivostei (bar instabilities).

obzor! astro-ph/0207050 Supermassive Black Hole Research in the Post-HST Era
Author: Laura Ferrarese

Daetsya obzor sovremennogo sostoyaniya del v issledovanii sverhmassivnyh chernyh dyr. Osoboe vnimanie udelyaetsya dannym, poluchennym na Kosmichekom teleskope.

obzor! astro-ph/0207053 Nuclear and High-Energy Astrophysics
Author: Fridolin Weber
Comments: 52 pages, 43 figures

Rassmatrivaetsya povedenie veshestva pri vysokih plotnostyah, obsuzhdayutsya kvarkovye zvezdy.

astro-ph/0207069 Chandra Observations of the Nucleus of M33
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.

astro-ph/0207074 Rayleigh Laser Guide Star Systems: Application to UnISIS
Authors: L.A. Thompson, S.W. Teare
Comments: 42 pages, 10 figures, accepted for publication in the September issue of PASP

Kak izvestno, atmosfera ochen' meshaet zemnym nablyudatelyam v optike i IK. Mozhno zapuskat' teleskopy v kosmos, no eto dorogo (hotya, "v kosmose dollar vesit men'she" B. Pachin'skii). Na Zemle stroyat sistemy s adaptivnoi optikoi (ob etom byla otlichnaya stat'ya D. Vibe v nedavnem "Zvezdochete".

Dlya otslezhivaniya sostoyaniya atmosfery primenyayut lazery (sozdanie t.n. "lazernoi zvezdy"). Ob etom i idet rech' v stat'e Tompsona i Tiara.

astro-ph/0207085 ROSAT Blank Field Sources I: Sample Selection and Archival Data
Authors: Ilaria Cagnoni et al.
Comments: 23 pages, 8 figures, accepted by ApJ main journal

Sputnik ROSAT zakonchil svoyu rabotu, odnako v ego arhivah hranit'sya mnogo informacii.

Avtory stat'i obsuzhdayut vydelennye imi neotozhdestvlennye istochniki. Eti ob'ekty harakterizuyutsya ochen' vysokim otnosheniem rentgenovskoi svetimosti k opticheskoi. Takimi harakteristikami mogut obladat' ili aktivnye yadra galaktik (v pervuyu ochered' lacertidy), ili odinochnye neitronnye zvezdy (i, vozmozhno, chernye dyry). V stat'e podrobno obsuzhdayutsya eti vozmozhnosti.

astro-ph/0207086 Constraints on Jupiters from observations of Galactic Bulge microlensing events during 2000
Authors: Yiannis Tsapras et al.

Est' li planety u mikrolinz? V stat'e avtory, ispol'zuya nedavnie nablyudeniya vos'mi sobytii mikrolinzirovaniya, delayut vyvod ob otsutstvii "yupiterov" u etih ob'ektov.

astro-ph/0207097 The magnification of SN 1997ff, the farthest known Supernova
Authors: Narciso Benitez et al.
Comments: 6 pages, 1 figure, submitted to ApJL

Uskoryaetsya li Vselennaya? Seichas nalichie znachitel'nogo vklada lyambda-chlena sleduet ne tol'ko iz nablyudenii dalekih sverhnovyh, no i iz dannyh po reliktovomu izlucheniyu i krupnomasshtabnoi strukture. Odnako, obsuzhdenie voprosa yavlyayutsya li dalekie sverhnovye tipa Ia horoshimi standartnymi svechami ne prekrashaetsya

V svoei stat'e avtory obsuzhdayut samuyu dalekuyu iz izvestnyh segodnya sverhnovyh (z~1.7, SN 1997ff). Dlya takih dalekih ob'ektov vazhen effekt gravitacionnogo linzirovaniya. Uchet etogo, kak ni stranno, privodit, po mneniyu avtorov stat'i, k eshe luchshemu soglasiyu s model'yu, v kotoroi Omega_M=0.35, Omega_Lambda = 0.65. Pri etom avtory na urovne 3 sigma isklyuchayut al'ternativnye modeli.

astro-ph/0207098 The Neutral Atomic Phases of the ISM in the Galaxy
Authors: M. G. Wolfire et al.
Comments: 69 pages plus 17 figures, submitted to ApJ

Znachitel'naya chast' mezhzvezdnoi sredy nahoditsya v vide neitral'nogo vodoroda. V svoei stat'e avtory detal'no issleduyut eto sostoyanie mezhzvezdnoi sredy.

Neitral'nyi vodorod v Galaktike mozhet sushestvovat' v vide holodnogo (T < 300 K) ili teplogo (10^4 K) gaza. Eti dve fazy sosushestvuyut v uzkom diapazone davlenii. V stat'e issleduetsya zavisimost' etogo diapazona ot galaktocentricheskogo rasstoyaniya, a takzhe privoditsya analiticheskaya approksimaciya takoi zavisimosti (chto udobno v prakticheskih primeneniyah). Model' predskazyvaet nalichie neitral'nogo holodnogo vodoroda na rasstoyaniyah 16-18 kpk ot centra Galaktiki.

astro-ph/0207104 The Millennium Arecibo 21-cm Absorption Line Survey. I. Techniques and Gaussian Fits
Authors: Carl Heiles and T.H. Troland
Comments: 70 pages, 20 figures.

astro-ph/0207105 The Millennium Arecibo 21-cm Absorption Line Survey. II. Properties of the Warm and Cold Neutral Media
Authors: Carl Heiles and T.H. Troland
Comments: 65 pages, 16 figures

V pervoi stat'e daetsya obzor teorii izmereniya chetyreh parametrov Stoksa. Zatem eta teoriya primenyaetsya v nablyudeniyam 79 istochnikov. Vo vtoroi stat'e detal'no issleduyutsya svoistva mezhzvezdnogo neitral'nogo vodoroda v okrestnostyah Solnca.

astro-ph/0207106 Deciphering The Last Major Invasion of the Milky Way Galaxy
Authors: Gerard Gilmore et al.
Comments: APJL 574 L39 (July 20, 2002)

"Pogoda byla prekrasnaya, princessa byla uzhasnaya...."

Nasha Galaktika - tozhe kannibal. Ona poedaet bolee melkih sosedei. Avtory stat'i obnaruzhili ostatki takogo epizoda. V rezul'tate spektroskopicheskogo izucheniya 2000 zvezd klassov F i G na rasstoyaniyah 0.5-5 kpk ot galakticheskoi ploskosti polucheno ukazanie na epizod "poglosheniya" nashei Galaktikoi sosedki 10-12 milliardov let nazad.

astro-ph/0207108 HIPPARCOS age-metallicity relation of the solar neighbourhood disc stars
Authors: A. Ibukiyama et al.
Comments: 45 pages, 21 figures, and 5 tables. Accepted to Astronomy & Astrophysics

V rabote poluchena zavisimost' vozrast-metallichnost' dlya 1658 zvezd, dlya kotoryh sushestvuyut tochnye izmereniya rasstoyanii po dannym sputnika HIPPARCOS. Sredi zvezd est' ob'ekty tonkogo i tolstogo diskov, a takzhe neskol'ko zvezd galo. Obsuzhdayutsya razlichiya dlya raznyh sostavlyayushih Galaktiki.

obzor! astro-ph/0207114 Star Formation from Galaxies to Globules
Authors: Bruce G. Elmegreen
Comments: accepted for ApJ, 42 pages, Dannie Heineman prize lecture

Odin iz luchshih specialistov v svoei oblasti daet obzor sovremennogo sostoyaniya nashego znaniya ob obrazovanii zvezd.



Arhiv statei, voshedshih v predydushie vypuski.

Razdely arhiva (s iyulya 2002 g.):
obzory, kosmologiya, neitrino, kosmicheskie luchi i gamma-astronomiya, galaktiki, AYaG, kvazary, mezhzvezdnaya sreda, zvezdy, sverhnovye, ostatki sverhnovyh, chernye dyry, neitronnye zvezdy, linzirovanie, Solnce, ekzoplanety, Solnechnaya sistema, akkreciya, tesnye dvoinye sistemy, gamma-vspleski, gravitacionnye volny, metody nablyudenii budushie nablyudatel'nye proekty, prochee.


Poleznye astronomicheskie ssylki.
Obzornye stat'i v astro-ph s 2001 g.

Sergei Popov

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