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The R.A.P. Project (Reviews of Astro-Ph) 2003

Mezhzvezdnaya sreda
(Arhiv Mezhzvezdnaya sreda:
v.2, 2004, v.1, 2002-2003)

Vypusk 60. 01-15 noyabrya 2003

astro-ph/0311087 Sluchainost' i SDSS: otkrytie samoi bol'shoi planetarnoi tumannosti (Serendipity and the SDSS: Discovery of the Largest Known Planetary Nebula on the Sky)
Authors: Paul C Hewett et al.
Comments: 12 pages including 4 figures. ApJ Letters in press

V dannyh Sloanovskogo cifrovogo obzora neba obnaruzhen ob'ekt, kotoryi vozmozhno yavlyaetsya samoi blizkoi i samoi bol'shoi (uglovoi razmer) planetarnoi tumannost'yu (sm. foto).

Eto daleko ne samaya krasivaya planetarnaya tumannost'. Levyi snimok poluchen v linii vodoroda (Ash Al'fa)+linii odnokratno ionizovannogo azota. Pravyi - v linii dvuhkratno ionizovannogo kisloroda. Razmer foto primerno 0.8 gradusa. Izobrazheni polucheny na teleskope Isaaka N'yutona. Na pravom snimke kruzhkom otmecheno polozhenie belogo karlika.

Issledovanie snimkov SDSS pokazalo nalichie oblasti ionizovannogo gaza razmerom bolee dvuh gradusov na dostatochno bol'shoi galakticheskoi shirote (+48 gradusov). Vblizi byl obnaruzhen goryachii belyi karlik PG 1034+001. Dopolnitel'nye issledovaniya byli provedeny na teleskope Isaaka N'yutona. Morfologiya oblasti i prisutstvie belogo karlika ukazyvayut na to, chto eto mozhet byt' planetarnaya tumannost'. Esli rasstoyanie do tumannosti poryadka 100-200 pk, to ee lineinyi razmer poryadka 3.5-7 pk. Vozrast tumannosti mozhno opredelit' lish' ochen' primerno v 100 000 let.

Tumannost' poluchila naimenovanie Hewett 1. Rasstoyanie do belogo karlika opredeleno lish' po spektru i potoku. Ono okazyvaetsya ravnym primerno 155 pk. Neobhodimy pryamye parallakticheskie izmereniya.


Vypusk 58. 01-17 oktyabrya 2003

astro-ph/0310311 Puzyri i sverhpuzyri (Bubbles and Superbubbles)
Authors: Y.-H. Chu et al.
Comments: 8 page, 5 figures

Odinochnaya massivnaya zvezda svoim zhestkim izlucheniem i vetrom porozhdaet vokrug sebya puzyr' (bubble) v mezhzvezdnoi srede, gruppa massivnyh zvezd sozdaet sverhpuzyr' (superbubble). V nastoyashee vremya est' ryad voprosov, kotorye bol'she vsego interesuyut uchenyh, zanimayushihsya dannoi problemoi:

  1. Pochemu vokrug nekotoryh O-zvezd net puzyrei?
  2. Naskol'ko goryach puzyr' iznutri?
  3. Chto proishodit na granice puzyrya, gde soprikasayutsya goryachii i holodnyi gaz?

Sleva - rentgenovskoe izobrazhenie puzyrya S308, poluchennoe na sputnike XMM-N'yuton, sprava - ego izobrazhenie v linii [OIII] 5007A. Central'naya zvezda puzyrya HD50896 otmechena krestom (v levom nizhnem uglu izobrazhenii).


Vypusk 56. 13-20 sentyabrya 2003

astro-ph/0309350 Prostranstvennoe raspredelenie oblastei HII v Galaktike (Spatial distribution of Galactic HII regions)
Authors: R. Paladini, G. DeZotti, R. D. Davies
Comments: 9 pages, 12 figures, 4 tables, accepted to MNRAS

V dannoi rabote priveden novyi detal'nyi analiz raspredeleniya oblastei HII (ionizovannogo vodoroda) v Galaktike. Dlya provedeniya dannogo issledovaniya byla ispol'zovana bolee polnaya baza dannyh, chem v predydushih rabotah, vklyuchayushaya v sebya 550 ob'ektov. Vnutri galakticheskoi orbity Solnca ("solnechnogo cikla") tolshina raspredeleniya HII okazalas' blizkoi k tolshine raspredeleniya OB-zvezd. Na bol'shih galaktocentricheskih rasstoyaniyah raspredelenie ob'ektov neskol'ko izognuto i ego tolshina uvelichivaetsya s udaleniem ot centra Galaktiki. Avtory takzhe podtverzhdayut obnaruzhennyi ranee gradient elektronnoi temperatury po radiusu Galaktiki.

Raspredelenie 550 oblastei HII v ploskosti Galaktiki.


Vypusk 50. 8-18 iyulya 2003

miniobzor astro-ph/0307245 Vozmozhnost' nablyudeniya svetovogo eho vokrug peremennyh zvezd i kosmicheskih vzryvov (Observability of Scattered-Light Echoes Around Variable Stars and Cataclysmic Events)
Authors: Ben E. K. Sugerman
Comments: 43 pages, 18 figures; Accepted for publication in the AJ

Svet ot zvezdy mozhet popast' pryamo k nablyudatelyu, a mozhet rasseyat'sya na pylevoi obolochke, okruzhayushei zvezdu. Rasseyannye fotony dostigayut nablyudatelya pozzhe. Napravlenie rasprostraneniya ih takzhe neskol'ko otlichaetsya ot napravleniya na istochnik: svet prihodit iz ego okrestnosti. Osobenno horosho etot effekt nablyudaetsya, esli istochnik izlucheniya yavlyaetsya peremennym (a luchshe vspyhivayushim). V etom sluchae (pri odinochnoi vspyshke i odnorodnom raspredelenii rasseivayushei sredy) vokrug istochnika budet nablyudat'sya rasshiryayusheesya svetovoe kol'co. Etot effekt nazyvaetsya "svetovoe eho".

V real'nosti effekt bolee slozhen: izluchenie istochnika mozhet menyat'sya slozhnym obrazom, pylevaya obolochka mozhet imet' proizvol'nuyu formu, obolochka ne tol'ko rasseivaet, no i pogloshaet rasseyannoe izluchenie, eho nado otdelit' ot fonovogo izlucheniya i t.d.


Dva rezhima vozniknoveniya svetovogo eho, opisannyh v stat'e:
a) "tolstoe" eho i b) "tonkoe" eho.

Obzor dostatochno ponyaten i interesen ne tol'ko specialistam.


astro-ph/0307273 Trehmernaya model' poglosheniya v Galaktike (A three-dimensional Galactic extinction model)
Authors: R. Drimmel, A. Cabrera-Lavers, M. Lopez-Corredoira
Comments: 12 pages, to be published in A&A

Postroena krupnomasshtabnaya trehmernaya model' poglosheniya sveta v Galaktike. Model' pozvolyaet bystro poluchit' velichinu A_V (oslablenie sveta) dlya lyuboi tochki vnutri diska Galaktiki.


astro-ph/0307330 Sistematicheskii sdvig v ocenkah mezhzvezdnogo magnitnogo polya (Systematic bias in interstellar magnetic field estimates)
Authors: Rainer Beck et al.
Comments: 10 pages with 2 figures. Accepted for publication in A&A

Odnoi iz vazhneishih sostavlyayushih mezhzvezdnoi sredy yavlyaetsya magnitnoe pole. Ego izmerenie yavlyaetsya neprostoi zadachei. Delo v tom, chto prihoditsya deistvovat' ne napryamik. Pole ocenivayut ili po ego vozdeistviyu na rasprostranyayusheesya elektromagnitnoe izluchenie (faradeevskoe vrashenie ploskosti polyarizacii), ili po sinhrotronnomu izlucheniyu chastic kosmicheskih luchei.

Mezhzvezdnaya sreda sil'no turbulizovana, i eto mozhet okazyvat' sushestvennoe vliyanie na ocenki magnitnogo polya. Avtory detal'no issleduyut vozmozhnye sistematicheskie effekty i prihodyat k vyvodu, chto ocenka po mere vrasheniya pri nalichii polozhitel'noi korrelyacii fluktuacii magnitnogo polya i elektronnoi plotnosti yavlyaetsya zavyshennoi (v sluchae antikorrelyacii vse budet naoborot). Polozhitel'naya korrelyaciya mezhdu plotnost'yu kosmicheskih luchei i magnitnym polem takzhe privodit k zavysheniyu ocenki magnitnogo polya. V chastnosti avtoram udaetsya ob'yasnit' rashozhdeniya v ocenkah polya, poluchennye dvumya opisannymi vyshe sposobami.



Vypusk 49. 01-07 iyulya 2003

astro-ph/0307013 Samoreguliruemyi progrev sverhnovymi v modelirovanii mezhzvezdnoi sredy (Self-regulating supernovae heating in interstellar medium simulations)
Authors: Graeme R Sarson et al.
Comments: 6 pages, 4 figures, to be published in: Magnetic fields and star formation: theory versus observations, eds: A. I. Gomez de Castro et al., Kluwer Acad. Publ., Dordrecht

Modelirovanie mezhzvezdnoi sredy yavlyaetsya ochen' trudnoi zadachei. Kartina sushestvenno trehmernaya (dlya sravneniya, ochen' slozhnaya zadacha predskazaniya pogody taki uproshaetsya vozmozhnost'yu kvazidvumernogo podhoda - atmosfera v nekotorom smysle ploskaya). Vazhen uchet magnitnyh polei, turbulentnosti, himicheskih processov, razlichnyh istochnikov energii i mehanizmov ohlazhdeniya. Pri etom hochetsya maksimal'no ne zadavat' parametry rukami i "krepko derzhat' granicy", a reshit' bolee-menee samosoglasovannuyu zadachu. Kratkoe rezyume: zadacha ne reshena. No postoyanno delayutsya novye i novye sushestvennye shagi v etom napravlenii.

Izyuminka dannoi raboty v tom, chto sverhnovye, dayushie bol'shoi vklad v energetiku mezhzvezdnoi sredy, raspredelny ne koe-kak i ne "kvadratno-gnezdovym" sposobom, a poyavlyayutsya tam, gde im i polozheno poyavlyat'sya: v plotnyh holodnyh oblakah, v kotoryh obrazuyutsya zvezdy-praroditeli sverhnovyh. Tak chto v etom smysle avtoram udalos' sdelat' sistemu samoreguliruyusheisya: temp sverhnovyh ne zadaetsya rukami, a poluchaetsya pri modelirovanii sam soboi.

Vypusk 48. 23-30 iyunya 2003


obzor astro-ph/0306541 Massivnye zvezdy i energeticheskii balans mezhzvezdnoi sredy. I. Vozdeistvie odinochnoi zvezdy massoi 60 mass Solnca (Massive stars and the energy balance of the ISM. I. The impact of an isolated 60 Msun star)
Authors: Tim Freyer, Gerhard Hensler, and Harold W. Yorke
Comments: 60 pages, 23 figures, 3 tables, accepted for publication in the Astrophysical Journal

Konechno, eta publikaciya - obzor. No, kak i pri nablyudenii nebesnyh ob'ektov, obzory byvayut dvuh tipov: "obzor vsego neba", kogda rassmatrivayutsya vse ob'ekty nahodyashiesya ot nas "na odnom rasstoyanii", i bolee redkie "glubokie prokoly", kogda smotryat tol'ko v odnom napravlenii, zato rassmatrivayut vse, ot samyh blizkih tel do predela vozmozhnostei. Dannaya publikaciya yavno otnositsya k "redkomu" vtoromu tipu. Ee osnovu sostavlyayut dvumernye gidrodinamicheskie raschety vozdeistviya vetra massivnoi zvezdy na okruzhayushuyu ee mezhzvezdnuyu sredu. No etot material raspolozhen v konce, a v nachale vy naidete opisanie togo chto takoe zony Stremgrena i ionizacionnye fronty, teoriyu vyduvaniya i dannye nablyudeniya puzyrei zvezdnogo vetra. (Etu chast' - pervye dva razdela - mozhno rekomendovat' prochitat' vsem.) Sami raschety tozhe interesny, oni uchityvayut perenos izlucheniya, vazhnyi dlya vetrov massivnyh zvezd, i sobstvennuyu evolyuciyu zvezdy s nachal'noi massoi 60Mo. Dvumernyi harakter raschetov pozvolyaet vosproizvesti neustoichivosti na granice veter - mezhzvezdnaya sreda.

Tipichnaya struktura puzyrya zvezdnogo vetra vokrug odinochnoi massivnoi zvezdy

astro-ph/0306543 Ukazaniya na szhatie oblastei formirovaniya massivnyh zvezd (Indications of Inflow Motions in Regions Forming Massive Stars)
Authors: Jingwen Wu, Neal J. Evans II
Comments: 6 pages, 2 figures. In press for Aug.1 ApJ Letters

Zvezdoobrazovanie svyazano so szhatiem oblastei mezhzvezdnogo gaza. Sootvetstvenno, v oblastyah zvezdoobrazovaniya dolzhny nablyudat'sya potoki gaza vnutr' (inflow motions). Eto ochen' medlennye dvizheniya, proishodyashie na fone slozhnoi struktury. Obnaruzhit' ih mozhno, izuchaya profili spektral'nyh linii v submillimetrovom diapazone. Dlya oblastei, gde v osnovnom obrazuyutsya malomassivnye zvezdy, takie dvizheniya gaza uzhe byli zaregistrirovany. S massivnymi zvezdami vse gorazdo slozhnee, t.k. process ih obrazovaniya protekaet ochen' burno. Poetomu sreda okazyvaetsya sil'no vozmushennoi. V etoi rabote vpervye polucheny rezul'taty, ukazyvayushie na nalichie "vtokovyh dvizhenii". Eto vazhno dlya ponimaniya togo pravil'no li my opisyvaem sam process formirovaniya zvezd.

Vypusk 47. 16-21 iyunya 2003


astro-ph/0306280 Obzor lokal'noi mezhzvezdnoi sredy v predelah 200 pk po dannym FUSE (FUSE Survey of the Local Interstellar Medium within 200 Parsec)
Authors: N. Lehner et al.
Comments: 30 pages, Accepted for publication in the ApJ

FUSE - The Far Ultraviolet Spectroscopic Explorer. Zapushen v 1999 g. Ul'trafioletovye missii ochen' vazhny dlya resheniya mnogih unikal'nyh zadach. Sredi nih i issledovaniya mezhzvezdnoi sredy.

Avtory predstavlyayut dannye, poluchennye na osnove analiza spektrov 30 belyh karlikov i odnogo subkarlika, nahodyashihsya na rasstoyaniyah do 200 pk. Polucheny novye sushestvennye dannye po nashei lokal'noi mezhzvezdnoi srede (vklyuchaya t.n. Mestnyi puzyr'). Odnim iz vazhnyh rezul'tatov yavlyaetsya otsutstvie molekulyarnogo vodoroda v Mestnom puzyre. Krome togo, avtory privodyat argumenty protiv nedavnei (menee 106 let) vspyshki sverhnovoi vblizi Solnca.


Vypusk 46. 1-15 iyunya 2003

miniobzor! astro-ph/0306034 Modeli himicheskoi evolyucii (Models of Chemical Evolution)
Authors: Francesca Matteucci
Comments: 14 pages, 7 figures, To appear in Carnegie Observatories Astrophysics Series, Vol. 4: Origin and Evolution of the Elements, ed. A. McWilliam and M. Rauch

Ochen' horoshii obzor po himicheskoi evolyucii. Pod etim terminom ponimaetsya evolyuciya obiliya razlichnyh himicheskih elementov v pervuyu ochered' v mezhzvezdnoi srede (nu a poskol'ku iz nee obrazuyutsya zvezdy, to i v zvezdah raznyh pokolenii). Avtor nachinaet s samyh osnov. Opisyvayutsya osnovnye podhody i modeli, prichem vse eto dovol'no prosto, ponyatno, so vsemi neobhodimymi ssylkami. Provodyatsya sravneniya predskazanii razlichnyh modelei s nablyudeniyami (v tom chisle i s nablyudeniyami istochnikov na bol'shih krasnyh smesheniyah).

Ob issledovanii himicheskogo sostava kvazarov i evolyucii ih "hozyaiskih galaktik" sm. stat'yu Hamanna i dr. "Quasar Elemental Abundances and Host Galaxy Evolution". Vazhnyi vyvod etoi stat'i sostoit v tom, chto galaktiki uspevali sushestvenno himicheski proevolyucionirovat' do obrazovaniya kvazara. Prochtenie obzora Francheski Matteuchi do chteniya etoi raboty budet ves'ma kstati.


Vypusk 42. 1-9 maya 2003


astro-ph/0305049 Turbulentnaya priroda flokullentnyh spiral'nyh struktur v galaktikah (A Turbulent Origin for Flocculent Spiral Structure in Galaxies)
Authors: Bruce G. Elmegreen et al.
Comments: accepted for ApJ, 31 pg, 9 figures

Seriya iz dvuh statei odnoi i toi zhe gruppy avtorov.

Flokullentnymi nazyvayut haoticheskie spiral'nye struktury v galaktikah. V naibolee razvitom vide flokullentnye spirali sostoyat kak by iz sluchaino razbrosannyh otrezkov spiral'nyh dug. Avtory proveli Fur'e analiz azimutal'nyh skanov 7 podobnyh galaktik. Okazalos', chto spektr moshnosti vedet sebya stepennym obrazom s pokazatelem -1 na bol'shih masshtabah i -1.7 na malyh. Takoe stepennoe povedenie - pryamoe ukazanie na nalichie u dannogo raspredeleniya fraktal'nyh svoistv. Bolee togo, nablyudaemye pokazateli stepeni sovpadayut so stepenyami raspredelenii skanov oblakov H I v Bol'shom Magellanovom Oblake, flokullentnyh pylevyh oblakov ya yadre Galaktiki, i spektra uglovogo raspredeleniya gaza po obzoram Mlechnogo Puti i Magellanovyh Oblakov.

Avtory delayut vyvod (i podtverzhdayut ego prostoi chislennoi model'yu), chto vse eti struktury porozhdeny odnoi i toi zhe prichinoi, a imenno krupnomasshtabnoi turbulentnost'yu mezhzvezdnoi sredy. Turbulentnost' porozhdaetsya v samyh krupnyh masshtabah iz-za sdvigovyh gravitacionnyh neustoichivostei i proyavlyaetsya snachala v vide struktur oblastei zvezdoobrazovaniya - flokullentnyh dugah. Dal'neishee razvitie turbulentnogo v storonu bolee melkih masshtabov porozhdaet ostal'nye perechislennye yavleniya.

6 galaktik iz dannoi raboty
Flokullentnaya spiral'naya galaktika NGC 4414

Vtoraya stat'ya astro-ph/0305050 posvyashena podobnomu issledovaniyu dvuh galaktik M33 i NGC 5055.


Vypusk 41. 25-30 aprelya 2003


obzor astro-ph/0304488 Astrofizika pyli v holodnyh oblakah (Astrophysics of Dust in Cold Clouds)
Authors: B.T. Draine
Comments:To appear in The Cold Universe: Saas-Fee Advanced Course 32. Berlin: Springer-Verlag, 2003 in press. 93 pages, 43 figures
obzor astro-ph/0304489 Mezhzvezdnye chasticy pyli (Interstellar Dust Grains)
Authors: B.T. Draine
Comments:To appear in Annual Review of Astronomy & Astrophysics, Vol. 41 (2003). 46 pages, 16 figures

Srazu dva bol'shih obzora po svoistvam mezhzvezdnoi pyli. Oba oni poyavyatsya v ochen' prestizhnyh izdaniyah. Pervyi obzor sostavili 9 lekcii, prochitannyh v ramkah populyarnyh shkol SAAS-Fee. Vtoroi - poyavitsya v Annual Reviews.

Konechno, obzory vo mnogom pereklikayutsya. Odnako, oni vo mnogom i razlichny. V pervom mnogo mesta udeleno sobstvenno holodnym oblakam, vtoroi - bolee skoncentrirovan imenno na povedenie pyli v mezhzvezdnoi srede.

Net nikakih somnenii, chto v techenie neskol'kih let eti stat'i budut naibolee standartnymi obzornymi ssylkami po teme.



Vypusk 40. 20-25 aprelya 2003

astro-ph/0304338 Trehmernoe raspredelenie mezhzvezdnoi sredy v nashei Galaktike (Three-Dimensional Distribution of the ISM in the Milky Way Galaxy: I. The HI Disk)
Authors: Hiroyuki Nakanishi and Yoshiaki Sofue
Comments: 14 pages, 13 figures
Journal-ref: PASJ, 2003, 55, 191

Ochen' trudno opredelit' formu chernogo zdaniya noch'yu bez sveta, osobenno, esli vy vnutri. Primerno po toi zhe prichine trudno issledovat' nashu Galaktiku. V svoei stat'e (pervoi iz serii rabot) yaponskie uchenye predstavlyayut raspredelenie neitral'nogo vodoroda v diske Galaktiki (sm. ris). Disk neitral'nogo vodoroda imeet radius poryadka 17 kpk (napomnim, chto Solnce raspolozheno primerno na polovine etogo rasstoyaniya ot centra). Disk nesimmetrichnyi i slegka iskrivlennyi vo vneshnih chastyah.


Raspredelenie neitral'nogo vodoroda v diske Galaktiki i shematicheskoe izobrazhenie spiral'nyh rukavov

Vypusk 38. 01-11 aprelya 2003

astro-ph/0304054 Novyi katalog sostava MZS v normal'nyh galaktikah (A new catalogue of ISM content of normal galaxies)
Authors: D. Bettoni et al.
Commets: 12 pages. 4 figures, 6 tables - A&A accepted

Sostavlen katalog po sostavu gaza v 1916 normal'nyh galaktikah. Konechno, uzuchenie kataloga dlya nespecialista zanyatie skuchnoe. Odnako obsuzhdenie (razdel 4), zanimayushee chut' bolee odnoi zhurnal'noi stranicy, soderzhit mnozhestvo primechatel'nyh faktov, kotorye mogut nebezinteresny tem, kto na ser'eznom urovne sledit za sovremennoi astrofizikoi v raznyh ee proyavleniyah.

obzor astro-ph/0304060 Rasseyanie optiki, ul'trafioleta i rentgena na mezhzvezdnoi pyli (Optical, UV, and X-Ray Scattering by Interstellar Dust Grains)
Authors: B.T. Draine
Commets: submitted to ApJ. 36 pages, 18 figures, Latex

Bol'shoi i podrobnyi obzor rasseyanie i poglosheniya opticheskogo, ul'trafioletovogo i rentgenovskogo izlucheniya na mezhzvezdnoi pyli.


(Arhiv Mezhzvezdnaya sreda:
v.2, 2004, v.1, 2002-2003)

Publikacii s klyuchevymi slovami: astrofizika - obzory - astro-ph
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