11.10.2004.
N'yuton smotrit na M31
05.10.2004.
Million sekund Kassiopei A
18.09.2004.
Rozhdenie lacertidy
16.09.2004.
Planeta okolo korichnevogo karlika
astro-ph/0410381
Chto my mozhem uznat' ob obrazovanii chernyh dyr, izuchaya rentgenovskie
dvoinye?
astro-ph/0410416
Novyi kompan'on Mlechnogo Puti: neobychnoe sharovoe skoplenie ili predel'no
malen'kaya galaktika-sputnik?
astro-ph/0410488
Massy, parallaks i relyativistskii taiming
PSR J1713+0747
Otdel'nye stat'i
Evolyuciya massivnyh dvoinyh chernyh dyr
Eksperimental'nye ukazaniya sushestvovaniya gravitacionnyh vspyshek
Chto my mozhem uznat' ob obrazovanii chernyh dyr, izuchaya rentgenovskie
dvoinye?
Novyi kompan'on Mlechnogo Puti: neobychnoe sharovoe skoplenie ili
predel'no
malen'kaya galaktika-sputnik?
Litii v ochen' bednyh metallami zvezdah: problemy standartnogo
pervichnogo nukleosinteza?
Kiborg-sistema kak platforma obrabotki izobrazhenii v astrobiologii / Pervye rezul'taty astrobiologicheskoi kiborg-sistemy
Blizhaishaya zvezda spektral'nogo klassa O3: komponent kratnoi sistemy
HD150136
Simmetriya v izmeneniyah dzhetov SS433 i rasstoyanie do nego
Variacii nachal'noi funkcii mass
Evolyuciya sverhnovyh v puzyryah vydutyh zvezdnym vetrom
Massy, parallaks i relyativistskii taiming dvoinogo pul'sara
PSR J1713+0747
Ogranicheniya na oslablenie dalekih sverhnovyh tipa Ia
Iz razdela physics
12th International Congress on Plasma Physics
Antropnye rassuzhdeniya v kosmologii: istoricheskii obzor
Polnyi Arhiv predydushih vypuskov.
Arhiv statei, voshedshih v vypuski s 01 iyulya 2002 g. po 31 marta 2003 g.
Razdely arhiva (s aprelya 2003 g.):
kosmologiya,
neitrino,
kosmicheskie luchi i gamma-astronomiya,
galaktiki, AYaG, kvazary,
nasha Galaktika,
mezhzvezdnaya sreda,
zvezdy,
sverhnovye,
ostatki sverhnovyh,
chernye dyry,
neitronnye zvezdy,
linzirovanie,
Solnce,
ekzoplanety,
Solnechnaya sistema,
akkreciya,
tesnye dvoinye sistemy,
gamma-vspleski,
gravitacionnye volny,
mehanizmy
izlucheniya,
chislennoe
modelirovanie,
dinamika,
mehanika
metody obrabotki
dannyh,
MGD,
metody
nablyudenii,
budushie nablyudatel'nye proekty,
prochee.
Poleznye astronomicheskie
ssylki.
Korotkoe esse ob elektronnyh preprintah.
Obzornye stat'i v astro-ph s 2001 g.
|
Obzory preprintov astro-ph
Vypusk N89
astro-ph za 18 - 25 oktyabrya 2004 goda:
izbrannye stat'i
Referaty otdel'nyh statei
obzor
astro-ph/0410364
Evolyuciya massivnyh dvoinyh chernyh dyr
(Massive Black Hole Binary Evolution)
Authors: David Merritt and Milos Milosavljevic
Comments: 63 pages, 14 figures
Kak my uzhe ne raz pisali, slivayushiesya dvoinye chernye dyry - samyi nadezhnyi istochnik gravitacionnyh voln dlya lazernyh interferometrov. Nazemnyi interferometr LIGO skoree vsego smozhet registrirovat' sliyaniya chernyh dyr zvezdnyh mass v nashei i sosednih galaktikah. Sverhmassivnye chernye dyry, podobnye prisutstvuyushei v centre Mlechnogo Puti, budut obnaruzheny na kosmicheskom detektore
LISA.
V privedennom obzore osnovnoe vnimanie udeleno putyam obrazovaniya dvoinyh sverhmassivnyh chernyh dyr (cherez sliyanie galaktik), nachal'nomu etapu sblizheniya chernyh dyr, kogda vliyanie gravitacionnogo izlucheniya prenebrezhimo malo (pod deistviem dinamicheskogo treniya o zvezdy) i nablyudatel'nym dannym, ukazyvayushim na sushestvovanie podobnyh sistem.
Na foto dva vozmozhnyh primera sverhmassivnyh dvoinyh chernyh dyr.
|
|
Sverhu - tonkie struktury radioistochnika 3C75 v skoplenii galaktik Abell 400 (radioizobrazhenie, VLA), nizhe - dvoinoe yadro galaktiki NGC6240 (foto Chandra) |
gr-qc/0410057
Eksperimental'nye ukazaniya sushestvovaniya gravitacionnyh vspyshek
(Experimental signatures of gravitational wave bursters)
Authors: Florian Dubath et al.
Comments: 4 pages, 2 figs
V zametke idet rech' o novom tipe istochnikov gravitacionnyh voln, kotorye vremya ot vremeni ispuskayut dostatochno korotkie impul'sy gravitacionnyh voln. Podobnymi svoistvami mogut obladat' istochniki myagkih povtornyh gamma-vspleskov (myagkie gamma-repitory =SGR), kotorye, kak segodnya predpolagayut, yavlyayutsya magnetarami - neitronnymi zvezdami so sverhsil'nymi polyami. Moshnost' gravitacionnyh vspyshek mozhet razlichat'sya takzhe sil'no, kak i moshnost' gamma-vspyshek etih ob'ektov: raspredelenie moshnosti vspyshek imeet stepennoi vid dN ~ E-1.6dE, a raspredelenie momentov vspyshek zametno otlichaetsya ot sluchainogo (nekorrelirovannogo). Krome etogo v stat'e rassmotreny voprosy registracii podobnyh vspyshek na sovremennyh gravitacionnyh detektorah.
astro-ph/0410381
Chto my mozhem uznat' ob obrazovanii chernyh dyr, izuchaya rentgenovskie
dvoinye?
(What can we learn about black-hole formation from black-hole X-ray
binaries?)
Authors: G. Nelemans
Comments: 6 pages, To appear in proceedings of "Massive Stars in
Interacting Binaries",
eds. Nicole St-Louis & Tony Moffat
Korotkaya i ochen' ponyatnaya stat'ya o tom, kakie dannye o chernyh dyrah
(zvezdy-praroditeli, skorosti otdachi, proishodit li vzryv pri obrazovanii
chernoi dyry, skol'ko veshestva teryaetsya pri obrazovanii chernoi dyry)
my mozhem uznat', izuchaya informaciyu
po tesnym dvoinym sistemam s chernymi dyrami.
Vyvody takie:
- chernye dyry obrazuyutsya so vzryvom i poterei massy;
- chernye dyry poluchayut kik pri rozhdenii,
t.e. process rozhdeniya ne simmetrichen.
astro-ph/0410416
Novyi kompan'on Mlechnogo Puti: neobychnoe sharovoe skoplenie ili predel'no
malen'kaya galaktika-sputnik?
(A New Milky Way Companion: Unusual Globular Cluster or Extreme Dwarf
Satellite?)
Authors: Beth Willman et al.
Comments: 17 pages, 10 figures. Resolution of Figure 1 degraded and
bottom
panel of Figure 4 only includes 10% of field stars to minimize figure size
Obnaruzhena gruppa golubyh zvezd SDSSJ1049+5103, plotnost' kotoroi prevyshaet
ozhidaemuyu dlya dannogo mestopolozheniya v Galaktike (rasstoyanie ot Solnca okolo
50 kpk).
Obrazovanie pohozhe na staroe skoplenie zvezd s nizkim soderzhaniem metallov.
Avtory predstavlyayut vsyu poluchennuyu po etomu ob'ektu informaciyu i rassuzhdayut
o ego prirode. Kak yasno iz nazvaniya, osnovnyh gipotez dve. Eto ili
sharovoe skoplenie, ili eshe odna galaktika-sputnik. I v tom, i v drugom
sluchae novootkrytoe obrazovanie yavlyaetsya netipichnym.
miniobzor
astro-ph/0410418
Litii v ochen' bednyh metallami zvezdah: problemy standartnogo
pervichnogo nukleosinteza?
(Lithium in Very Metal-poor Dwarf Stars - Problems for Standard Big Bang
Nucleosynthesis?)
Authors: David L. Lambert
Comments: 18 pages, 5 figures
Standartnyi scenarii pervichnogo nukleosinteza, parametry kotorogo vyvedeny iz
nablyudenii anizotropii reliktovogo izlucheniya (po dannym
WMAP) predskazyvaet opredelennoe obilie izotopov 6Li i 7Li. Pri etom obilie 7Li primerno na tri poryadka vyshe, chem nablyudaemoe v samyh bednyh metallami zvezdah, a obilie 6Li, naoborot, na tri poryadka nizhe, chem v etih zvezdah.
V obzore obsuzhdaetsya vozmozhnost' razresheniya dannogo protivorechiya v ramkah standartnogo scenariya pervichnogo nukleosinteza.
cs.CV/0401004
Kiborg-sistema kak platforma obrabotki izobrazhenii v astrobiologii
(Cyborg Systems as Platforms for Computer-Vision Algorithm-Development
for Astrobiology)
Authors: Patrick C. McGuire et al.
Comments: 4 pages, 6 figures
cs.CV/0409031
Pervye rezul'taty astrobiologicheskoi kiborg-sistemy
(Field Geology with a Wearable Computer: First Results of the Cyborg
Astrobiologist System)
Authors: Patrick C. McGuire et al.
Comments: 7 pages, 6 figures
Gruppa issledovatelei, vdohnovlennaya ideei fil'ma "Matrica" (pervogo), razrabotala prototip kiborg-sistemy obrabotki geologicheskih i astrobiologicheskih izobrazhenii. Slovo Kiborg zdes' oboznachaet, chto chast' obrabotki (nachal'naya) vypolnyaetsya komp'yuterom, a bolee intellektual'naya - chelovekom. Na fotografii pokazany pervye rezul'taty raboty "zheleznoi" chasti kiborg-sistemy: vydelenie raznotipnyh chastei izobrazheniya.
astro-ph/0410447
Blizhaishaya zvezda spektral'nogo klassa O3: komponent kratnoi sistemy
HD150136
(The Nearest Star of spectral type O3: A Component of the Multiple System
HD150136)
Authors: V.S. Niemela, R.C. Gamen
Comments: 7 pages, 4 figures, accepted for MNRAS
Issledovanie vysokotochnyh (s bol'shim otnosheniem signal/shum) spektrov sistemy HD150136 pokazalo, chto samyi yarkii ee komponent imeet spektral'nyi klass O3. Po etim zhe spektram udalos' naiti vtoruyu sistemu peremeshayushihsya spektral'nyh linii i ustanovit' period odnoi iz komponent etoi kratnoi sistemy, ravnyi 2.6 dnyam (chto podtverdilo menee tochnye predvaritel'nye rezul'taty). Issledovanie otnositel'nyh amplitud linii He II, N V i N IV pozvolilo ocenit' massu zvezdy O3 sleduyushim obrazom: 18<M<27Mo.
astro-ph/0410456
Simmetriya v izmeneniyah dzhetov SS433 i rasstoyanie do nego
(Symmetry in the changing jets of SS433 and its true distance from us)
Authors: K.Blundell, M.Bowler
Comments: accepted by ApJ Letters
Na serii glubokih radioizobrazhenii dzhetov SS433, poluchennyh v hode bolee chem dvuh precessionnyh ciklov (&gr;2x163 dnya), byli vyyavleny sistematicheskie otkloneniya parametrov dzhetov ot standartnoi kinematicheskoi modeli dlitel'nost'yu do desyati dnei. Prichem eti izmeneniya odinakovo proyavlyalis' v oboih dzhetah (s uchetom konechnoi skorosti rasprostraneniya fotonov). Sledstviem dannoi raboty yavlyaetsya nezavisimaya ocenka skorosti veshestva v dzhetah (ot 0.24 do 0.28 c) i takzhe nezavisimaya ocenka rasstoyaniya do SS 433 (5.5+/-0.2 kpk).
Bolee podrobno skorost' veshestva v dzhetah SS433 rassmatrivaetsya v drugoi stat'e teh zhe avtorov:
astro-ph/0410457.
astro-ph/0410461
Variacii nachal'noi funkcii mass
(Variation of the IMF)
Authors: Pavel Kroupa, Carsten Weidner
Comments: 13 pages, to appear in IMFat50: The Initial Mass Function 50
years
later, ed: E. Corbelli, F. Palla, and H. Zinnecker, Kluwer Academic
Publishers; a meeting held at the Abbazia di Spineto, Tuscany, Italy --
May
16-20, 2004
Dovol'no interesnaya stat'ya ot odnogo iz avtoritetov v oblasti nachal'noi
funkcii mass (NFM).
Sut' sostoit v detal'nom obsuzhdenii razlichii mezhdu zvezdnoi NFM i
galakticheskoi NFM.
Pervaya universal'na. Ona sootvetstvuet gruppe zvezd, rozhdennoi v odnoi
vspyshke zvezdoobrazovaniya (naprimer, v odnom skoplenii).
Raznica mezhdu raznymi skopleniyami budet lish' v znachenii maksimal'noi massy:
v malen'kih skopleniyah net zvezd bol'shoi massy.
Vtoraya - galakticheskaya NFM - obrazuetsya putem slozheniya individual'nyh
zvezdnyh. No! Poskol'ku dlya kazhdogo skopleniya est' verhnii predel massy
zvezdy (zavisyashii ot massy samogo skopleniya), to summarnaya NFM ne budet
takoi zhe kak individual'nye. Ona budet bolee krutoi (t.e. dolya malomassivnyh
zvezd budet bol'she).
Na vsyakii sluchai poyasnim eshe raz podhod avtorov. V malen'kih skopleniyah
massivnyh zvezd net ne potomu, chto eto maloveroyatno, a prosto potomu, chto
oni tam ne obrazuyutsya. (Poyasnim analogiei. Pisatel' s nebol'shim literaturnym
darovaniem ne proizvodit shedevry rezhe, chem genial'nyi pisatel' - skazhem ne 1
iz 10, a 1 iz 100 knig - a prosto ne pishet shedevrov: est' potolok).
T.o., rassuzhdayut avtory, sravnivat' NFM individual'nyh skoplenii s funkciyami
mass galaktik nekorrektno, esli ne uchityvat' opisannogo vyshe effekta
ukrucheniya NFM.
Vtoroi vyvod mozhno sformulirovat' tak.
Razlichiya v NFM mezhdu skopleniyami svyazany s razlichiem massy plyus effektom
sluchainoi vyborki. Razlichiya zhe mezhdu galaktikami budut obuslovleny
razlichiyami v tempe zvezdoobrazovaniya (chem vyshe temp, tem vyshe maksimal'naya
massa skoplenii). Zametim, chto opyat' zhe spektr mass skoplenii mozhet byt' i
universal'nym, i v igru vstupaet uzhe massa galaktiki....
Eshe vazhnye zaklyucheniya.
1. Temp sverhnovyh vtorogo tipa, rasschitannyi po standartnoi zvezdnoi NFM,
okazyvaetsya zavyshennym, esli prilagat' ego ko vsei galaktike.
2. Obogashenie galaktiki tyazhelymi elementami, rasschitannoe po zvezdnoi
NFM, opyat' zhe zavysheno.
obzor
astro-ph/0410464
Evolyuciya sverhnovyh v puzyryah vydutyh zvezdnym vetrom
(The Evolution of Supernovae in Circumstellar Wind-Blown Bubbles I.
Introduction and One-Dimensional Calculations)
Authors: Vikram V. Dwarkadas (University of Chicago)
Comments: 42 pages, 13 figures, subm. to ApJ
V obzore dostatochno podrobno rassmotrena sleduyushaya problema: massivnye zvezdy (>8-10Mo), vzryvayushiesya kak sverhnovye, obladayut ochen' sil'nym zvezdnym vetrom. Za vremya zhizni takoi zvezdy na glavnoi posledovatel'nosti i na bolee pozdnih evolyucionnyh stadiyah veter vyduvaet vokrug zvezdy kavernu razmerom do neskol'kih desyatkov parsek. Mezhzvezdnoe veshestvo, zapolnyavshee dannuyu oblast', okazyvaetsya sgrebennym v holodnyi, tonkii i ochen' plotnyi sloi. Sbroshennaya obolochka sverhnovoi, takim obrazom, vzaimodeistvuet ne s odnorodnoi sredoi, a s vydutoi vetrom kavernoi. Vazhneishim parametrom okazyvaetsya otnoshenie massy sgrebennogo vetrom veshestva k masse sbroshennoi obolochki sverhnovoi.
Opisannye rezul'taty byli polucheny dostatochno davno, no v dannom obzore oni dopolneny poslednimi detalyami i podrobno razobrany.
astro-ph/0410488
Massy, parallaks i relyativistskii taiming dvoinogo pul'sara
PSR J1713+0747
(Masses, Parallax, and Relativistic Timing of the PSR J1713+0747 Binary
System)
Authors: Eric M. Splaver et al.
Comments: 12 pages, Accepted by ApJ
Dvoinoi pul'sar PSR J1713+0747 sostoit iz neitronnoi zvezdy vokrug kotoroi s periodom 68 dnei obrashaetsya belyi karlik. 12 let nablyudenii pozvolili dovesti srednyuyu tochnost' izmereniya momentov prihoda impul'sov do 200 ns i ocenit' sleduyushie parametry sistemy:
MNS | = 1.3+/-0.2Mo |
MWD | = 0.28+/-0.03Mo |
&pi | = 0.89+/-0.08 mas |
D | = 1.1+/-0.1 kpk |
Esli skombinirovat' chisto nablyudatel'nuyu ocenku massy neitronnoi zvezdy s teoreticheskoi zavisimost'yu orbital'nyi period - massa yadra predsverhnovoi, to dlya neitronnoi zvezdy poluchitsya bolee vysokaya ocenka massy
obzor
astro-ph/0410501
Ogranicheniya na oslablenie dalekih sverhnovyh tipa Ia
(Limiting the dimming of distant type Ia supernovae)
Authors: Linda Ostman and Edvard Mortsell
Comments: 19 pages, 11 figures
Dalekie sverhnovye tipa Ia (yavlyayushiesya horoshimi "standartnymi svechami") vyglyadyat slabee, chem oni dolzhny byt' v ploskoi Vselennoi zapolnennoi obychnym veshestvom.
Prinyatoe segodnya ob'yasnenie etogo fakta - Vselennaya v osnovnom zapolnena temnoi energiei, iz-za chego ona rasshiryaetsya uskorenno, sverhnovye okazyvayutsya dal'she i svetyat, sootvetstvenno, slabee.
No, v principe, sushestvuyut i drugie vozmozhnye istochniki dlya podobnogo oslableniya. V dannom obzore rassmotreny tol'ko dva iz nih:
- mezhgalakticheskaya seraya pyl', oslablyayushaya svetimost' istochnika, no ne izmenyayushaya ego cvet;
- prevrashenie (oscillyacii) fotonov v aksiony.
My budem starat'sya hotya by perechislit' interesnye (dlya shirokoi publiki)
stat'i, poyavivshiesya v razdele
physics
(vklyuchaya cross-listing).
proceedings
12th International Congress on Plasma Physics
V razdele Physics
avtory prodolzhayut vykladyvat'
materialy 12-go Mezhdunarodnogo kongressa po fizike plazmy.
physics/0410144
Antropnye rassuzhdeniya v kosmologii: istoricheskii obzor
(Anthropic Reasoning in Cosmology: A Historical Perspective)
Authors: Stefano Bettini
Comments: 27 pages To appear soon in: Stoeltzner M. Weingartner P.
eds.: Formale Teleologie und Kausalitat, Mentis Verlag, Paderborn
Navernoe, luchshe prochitat' izvestnuyu
knigu
(The Anthropic Cosmological Principle (Oxford Paperbacks), John D. Barrow,
Frank J. Tipler),
posvyashennuyu antropnomu principu, a takzhe, vozmozhno bolee svezhuyu kriticheskuyu
stat'yu Smolina. Odnako za neimeniem knigi stoit posmotret' dannyi obzor.
On posluzhit horoshim dopolneniem k stat'yam Vilenkina, Linde, Smoilna i dr.,
dostupnym v Arhive.
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