Rambler's Top100Astronet    
  po tekstam   po klyuchevym slovam   v glossarii   po saitam   perevod   po katalogu
 

Efir na radio Svoboda - 2


Podpiska na rassylku obzorov astro-ph na Subscribe.Ru





  • 17.06.2004. Nablyudeniya Yupitera na XMM-Newton
  • 15.06.2004. Novaya obrabotka glubokogo habblovskogo snimka
  • 24.03.2004. Obzor neba po dannym SIGMA

    Soderzhanie i bystryi perehod k razdelam obzora


    Stat'i nedeli
    "Luchshie iz luchshih"

  • astro-ph/0406274
    Bolee informativnaya kartinka Habblovskogo glubokogo snimka

  • astro-ph/0406319
    Astrofizicheskie dzhety i istecheniya


    Otdel'nye stat'i
  • Galakticheskie okrestnosti Solnca
  • Bolee informativnaya kartinka Habblovskogo glubokogo snimka
  • Pryamye poiski nebarionnoi temnoi materii: Obzor eksperimentov
  • Dinamika skopleniya Abell 2125
  • Kosmologiya s peremennoi skorost'yu sveta
  • Fizika dzhetov, nesomyh E x B
  • Astrofizicheskie dzhety i istecheniya
  • Pervichnyi nukleosintez dlya peshehodov
  • Otkrytie klassov galaktik pri avtomaticheskoi klassifikacii
  • Pervye nablyudeniya Yupitera na XMM-Newton
  • Energetika sistem chernaya dyra - akkrecionnyi disk s magnitnoi svyaz'yu pri nizkih tempah akkrecii
  • Raschety nelineinyh zvezdnyh pul'sacii: Zvezdy RR Lyrae
  • Poluchenie sverhvysokokontrastnyh izobrazhenii s pomosh'yu gaussovoi aperturnoi maski


    Iz razdela physics
  • Feierabend i fizika


    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 N80

    astro-ph za (01) - 12 - 20 iyunya 2004 goda: izbrannye stat'i

    V etot vypusk voshli kak stat'i za 12-20 iyunya, tak i nekotorye raboty za 01-11 iyunya, ne vklyuchennye v predydushii vypusk v svyazi s nedostatkom vremeni v hode raboty konferencii VAK-2004.

    Meropriyatie proshlo uspeshno. Nadeemsya, chto provedenie vserossiiskih forumov astronomov stanet horoshei tradiciei.


    Referaty otdel'nyh statei


    astro-ph/0405167 Galakticheskie okrestnosti Solnca (The Solar Galactic Environment)
    Authors: P.C.Frisch
    Comments: 8 pages, 3 figures

    Eta rabota, kak nazval ee avtor, "kombinirovannoe issledovanie" geliosfery (do 500AE) i blizhaishih mezhzvezdnyh okrestnostei (do 106AE) [Hotya, kak takoe mozhno skombinirovat'? Masshtaby razlichayutsya na 3 poryadka]. Dinamika oblakov podtverzhdaet sushestvovanie sverhobolochki (supershell) vokrug associacii Skorpiona-Centavra. Solnce voshlo v eto skoplenie mezhzvezdnyh oblakov uzhe posle ego obrazovaniya.


    Shema Solnechnoi okrestnosti po Frichu


    astro-ph/0406274 Bolee informativnaya kartinka Habblovskogo glubokogo snimka (A more informative picture of the HST Ultra Deep Field)
    Authors: Nicholas Wherry, Michael R. Blanton, David W. Hogg
    Comments: 3 pages, astro-ph only. If the PS file doesn't properly display (because of a strange arxiv bug), try the PDF version. Code and full resolution JPEG available at http://cosmo.nyu.edu/hogg/visualization/

    Avtory pereobrabotali glubokii Habblovskii snimok. Sut' zaklyuchalas' v tom, chtoby popytat'sya sozdat' izobrazhenie, sposobnoe na real'nyh ustroistvah (monitory, printery) peredat' shirokii dinamicheskii diapazon ishodnyh cvetov. Kak pishut avtory, osobenno zametno uluchshenie izobrazhenii yarkih ob'ektov (naprimer, central'nye oblasti yarkih galaktik). Vidny gradient cvetov v galaktikah, spiral'naya struktura i t.p. Central'nye oblasti yarkih ellipticheskih galaktik vyglyadyat ne belymi, a krasnymi. Krome togo, dlya izobrazheniya dalekih galaktik (s zametnym krasnym smesheniem) byla ispol'zovana drugaya palitra.

    Detali mozhno naiti v rabote avtorov Lupton et al 2004, PASP, 116, 133--137. Samu programmu obrabotki mozhno skachat'.



    obzor astro-ph/0406285 Pryamye poiski nebarionnoi temnoi materii: Obzor eksperimentov (Direct Non-baryonic Dark Matter Search - An experimental Review)
    Authors: S. Fiorucci
    Comments: 9 pages, 3 figures, 2 tables

    Chasticy temnoi materii ochen' slabo vzaimodeistvuyut s obychnym veshestvom, inache by ih uzhe davno obnaruzhili i issledovali. Do sih por ne yasno, kakoi imenno sort chastic (ili sorta) obrazuyut temnoe veshestvo i, sootvetstvenno, v kakie specificheskie dlya dannyh sortov chastic reakcii oni mogut vstupat'. No vse modeli predskazyvayut, chto "temnye" chasticy budut rasseivat'sya na obychnom veshestve (protonah, neitronah, elektronah i sostavlennyh iz nih yadrah i atomah). Eshe odnoi slozhnost'yu poiska podobnyh chastic, yavlyaetsya nalichie pochti izotropnogo i pochti stacionarnogo ih fona, kotoryi nado vydelit' na fone teplovyh i prochih shumov detektora.

    V celom ryade eksperimentov (kak zakonchennyh, tak i planiruemyh) obnaruzhenie temnoi materii bylo libo osnovnoi cel'yu, libo pobochnoi vozmozhnost'yu.


    Tablica zavershennyh i prodolzhayushihsya eksperimentov

    A sam obzor ochen' interesnyi i ponyatnyi.


    astro-ph/0406292 Dinamika skopleniya Abell 2125 (The Dynamics of Abell 2125)
    Authors: Neal A. Miller at al.
    Comments: 34 pages, 3 figures, appear in ApJ

    Dlya skopleniya galaktik Abell 2125, raspolozhennogo na z~0.25, byli izmereny polozheniya (uglovye) i luchevye skorosti 371 galaktiki. Izmereniya velis' v techenii neskol'kih let na 3.5 m teleskope WIYN (Kitt Peak) i na 4 m teleskope Mayall (NOAO). Parallel'no opticheskim velis' takzhe radio i rentgenovskie nablyudeniya. Posle izmereniya luchevyh skorostei 224 galaktiki byli otneseny k skopleniyu.

    Dannoe issledovanie pokazalo, chto skoplenie yavlyaetsya ne odnorodnym, v nem nablyudayutsya opredelennye statisticheski znachimye substruktury. Skoree vsego oni yavlyayutsya rezul'tatom massovyh sliyanii galaktik v skoplenii.


    Substruktury v skoplenii Abell 2125.
    Chernye kontury - rentgenovskie nablyudeniya (dannye ROSAT), podpisany krupnye vyyavlennye struktury. Krasnye treugol'niki - vysokoskorotsnye galaktiki, sinie plyusy - nizkoskorostnye, zelenye kruzhki - galaktiki osnovnoi chasti skopleniya.


    gr-qc/0406027 Kosmologiya s peremennoi skorost'yu sveta (A varying-c cosmology)
    Authors: Hossein Shojaie, Mehrdad Farhoudi
    Comments: 18 pages

    Vot vpolne nauchnyi primer postroeniya al'ternativnoi kosmologicheskoi teorii, v kotoroi skorost' sveta menyaetsya so vremenem (s vozrastom Vselennoi). Rekomenduyu prochitat' etu stat'yu vsem, interesuyushimsya gravitaciei, kak s ortodoksal'nyh, tak i s al'ternativnyh pozicii. Pravda v etoi stat'e dostatochno slozhnaya matematika (kak i v drugih stat'yah dannogo napravleniya).


    astro-ph/0406318 Fizika dzhetov, nesomyh E x B (The Physics of E x B-Drifting Jets)
    Authors: Wolfgang Kundt, Gopal Krishna
    Comments: 13 pages, 3 figures, submitted to JAA

    Dzhety v astrofizicheskih ob'ektah mogut porozhdat'sya dvumya razlichnymi sposobami:

    • Gidrodinamicheskim, kogda s samogo nachala osnovnaya energiya soderzhitsya v kineticheskoi energii veshestva dzhetov. Povedenie takih strui opisyvaetsya chistoi gidrodinamikoi, elektromagnitnye polya v nih igrayut pobochnuyu rol'.
    • Elektromagnitnye, kogda osnovnaya energiya snachala perenositsya vektorom Pointinga (E x B, kak pishut avtory stat'i). Energiya postepenno peredaetsya uskoryaemoi plazme, postupayushei v dzhet ili porozhdaemoi ego sverhkriticheskim eklekticheskim polem (v etom sluchae plazma budet e+/e-).
    Gidrodinamicheskie dzhety voznikayut v obychnyh zvezdah i protozvezdah, elektromagnitnye - v radiopul'sarah, aktivnyh yadrah galaktik, ozhidaetsya, chto oni mogut poyavlyat'sya u vrashayushihsya chernyh dyr.

    Avtoram stati udalos' naiti reshenie, kotoroe opisyvaet vse etapy "zhizni" dzheta: ego vozniknovenie, rasprostranenie i okonchanie. Nekotorye elementy poluchennogo resheniya pokazany na risunkah.



    obzor astro-ph/0406319 Astrofizicheskie dzhety i istecheniya (Astrophysical Jets and Outflows)
    Authors: Elisabete M. de Gouveia Dal Pino
    Comments: pdf file, 20 pages, 12 figures

    Obzor posvyashennyi astrofizicheskim dzhetam (v osnovnom gidrodinamicheskim, v otlichie ot predydushei stat'i astro-ph/0406319). V obzore rassmotreny sleduyushie temy: nablyudaemyi svoistva dzhetov YSO (molodyh zvezdnyh ob'ektov), AGN, mikrokvazarov, teoriya, chislennoe modelirovanie, priroda "uzlov" v dzhetah, rasprostranenie dzhetov, ih precessiya, tormozhenie, vzaimodeistvie so sredoi, "nakonechniki" dzhetov (struktury na ih dal'nih koncah), vliyanie magnitnyh polei, relyativistskie dzhety, mehanizmy kollimacii i, nakonec, nereshennye voprosy.


    miniobzor astro-ph/0406320 Pervichnyi nukleosintez dlya peshehodov (BBN For Pedestrians)
    Authors: James P. Kneller, Gary Steigman
    Comments: 10 pages, 15 figures, submitted to New Journal of Physics

    Prosteishaya, standartnaya model' pervichnogo nukleosinteza (Big Bang Nucleosynthesis =BBN) predpolagaet nalichie 3 sortov neitrino i otsutstvie sushestvennoi asimmetrii elektronnyh neitrino. Pri takih predpolozheniyah v etoi modeli ostaetsya tol'ko odin parametr: otnoshenie chisla barionov k chislu fotonov η. Znaya zavisimost' kolichestva pervichnyh nuklidov (D, 4He, 7Li, 3He) mozhno popytat'sya opredelit' znachenie η. No opredelit' kolichestva pervichnyh nuklidov ne prosto: popadaya v zvezdy nekotorye iz nih oni vygorayut, a mezhzvezdnaya sreda (s pervichnymi elementami) zasoryaetsya (vetrom teh zhe zvezd). V ne standartnyh BBN-modelyah bol'she svobody i parametrov. Vse eto rassmatrivaetsya v obzore, ob'em kotorogo rasschitan na nebol'shuyu peshehodnuyu progulku.


    astro-ph/0406323 Otkrytie klassov galaktik pri avtomaticheskoi klassifikacii (Class Discovery in Galaxy Classification)
    Authors: David Bazell and David J. Miller

    Novye massovye obzory astrofizicheskih ob'ektov (v pervuyu ochered' galaktik i zvezd) postavili problemu avtomaticheskoi ih klassifikacii, poskol'ku delat' eto v ruchnuyu teper' fizicheski nevozmozhno. Mnogie algoritmy klassifikaciya prohodyat period "obucheniya", kogda na vhod algoritma podayutsya special'nye, klassificirovannye vruchnuyu vyborki ob'ektov. Odnako praktika podobnoi klassifikacii pokazala, chto sdelannye vruchnuyu vyborki ne slishkom horoshi: v gruppah ob'ektov, otnesennyh v etih vyborkah k odnomu klassu, algoritm nahodit vazhnye dlya klassifikacii razlichiya. Samoe interesnoe, mogut okazat'sya polnost'yu propushennymi celye novye klassy ob'ektov! V dannoi rabote avtory privodyat takoi "novyi klass" galaktik obnaruzhennyi sistemoi avtomaticheskoi klassifikacii.


    astro-ph/0406340 Pervye nablyudeniya Yupitera na XMM-Newton (First observation of Jupiter by XMM-Newton)
    Authors: G. Branduardi-Raymont et al.
    Comments: 7 pages, 9 figures; to be published in Astronomy & Astrophysics

    Polucheny pervye izobrazheniya Yupitera na sputnike XMM-Newton.


    Rentgenovskoe (avroral'noe) izluchenie Yupitera bylo otkryto eshe v 80-e gg. na observatorii Einshtein. Zatem v 90-e Yupiter aktivno izuchalsya s borta sputnika ROSAT. Sovsem nedavno byli provedeny nablyudeniya Yupitera na Chandre.

    Na verhnem risunke dano summarnoe izobrazhenie, sozdannoe putem slozheniya signala ot priborov EPIC-pn, MOS1, MOS2.

    Na nizhnem risunke privedeno sglazhennoe izobrazhenie, poluchennoe priborom EPIC-pn (European Photon Imaging Camera-PN). Krasnyi cvet sootvetstvuet bolee myagkim rentgenovskim lucham (0.2-0.5 keV), sinie - bolee zhestkim (0.7-2 keV). Vidno, chto izluchenie ot ekvatorial'noi oblasti zhestche. Svoistva etogo izlucheniya okazalis' blizki k svoistvam rentgena iz ekvatorial'noi zony Saturna. A vot izluchenie ot polyusov u dvuh gigantov razlichno.


    astro-ph/0406353 Energetika sistem chernaya dyra - akkrecionnyi disk s magnitnoi svyaz'yu pri nizkih tempah akkrecii (Energetics of Black Hole-Accretion Disk System with Magnetic Connection: Limit of Low Accretion Rate)
    Authors: Li-Xin Li
    Comments: 28 pages, including 11 figures; accepted in PASJ

    Rassmotrena model' chernoi dyry, okruzhennoi akkrecionnym diskom, s umerenno sil'noi magnitnoi svyaz'yu, kogda samaya vnutrennyaya chast' akkrecionnogo diska vrashaetsya tverdotel'no iz-za krupnomasshtabnogo magnitnogo polya. Pokazano, chto esli moment vrasheniya chernoi dyry prevoshodit nekotoroe kriticheskoe znacheniya

    a > acr = 0.3594 M,

    to energiya vrasheniya chernoi dyry nachinaet vkachivat'sya v disk i mozhet povysit' ego svetimost' na poryadki velichiny.

    V protivopolozhnom sluchae (pri a < acr) dvizhenie vnutrennei oblasti diska opredelyaetsya magnitnym polem, a ego vnutrennyaya granica raspolagaetsya na radiuse korotacii (tam, gde Keplerovskaya orbital'naya uglovaya skorost' stanovitsya ravnoi skorosti vrasheniya chernoi dyry). Svetimost' diska v etom sluchae rezko snizhaetsya po sravneniyu so standartnoi (al'fa) model'yu.


    miniobzor astro-ph/0406373 Raschety nelineinyh zvezdnyh pul'sacii: Zvezdy RR Lyrae (Automated Nonlinear Stellar Pulsation Calculations: Applications to RR Lyrae stars. The Slope of the Fundamental Blue Edge and the First RRd Model Survey)
    Authors: R. Szabo et al.
    Comments: 13 pages, 6 figures, accepted in A&A

    V dannoi stat'e opisana metodologiya raschetov pul'sacii zvezd i izmeneniya ih povedeniya vdol' evolyucionnyh trekov.


    astro-ph/0406374 Poluchenie sverhvysokokontrastnyh izobrazhenii s pomosh'yu gaussovoi aperturnoi maski (High Contrast Imaging with Gaussian Aperture Pupil Masks)
    Authors: J.H. Debes & J. Ge
    Comments: 19 pages, 5 figures, accepted to PASP

    Pri poiske vnesolnechnyh planet po otrazhennomu imi svetu nado kak-to borot'sya so sverhmoshnym i ochen' blizko raspolozhennym istochnikom sveta - zvezdoi, ryadom s kotoroi i ishutsya planety. Gaussova aperturnaya maska - metod obrabotki izobrazhenii, snizhayushii blesk zvezdy na bol'shih rasstoyaniyah ot nee. V chastnosti, v eksperimentah na 100" teleskope Maunt Vilson (Mt.Wilson) v infrakrasnom diapazone udalos' dostich' kontrasta ~4x10-5 na masshtabe 10λ/D.




    My budem starat'sya hotya by perechislit' interesnye (dlya shirokoi publiki) stat'i, poyavivshiesya v razdele physics (vklyuchaya cross-listing).

    physics/0406079 Feierabend i fizika (Feyerabend and physics)
    Authors: Karl Svozil
    Comments: 14 pages, presented at the International Symposium Paul Feyerabend 1924-1994. A philosopher from Vienna, University of Vienna, June 18-19, 2004

    Korotkoe esse, posvyashennoe izvestnomu filosofu Polu Feierabendu.


    Publikacii s klyuchevymi slovami: astro-ph - elektronnye preprinty
    Publikacii so slovami: astro-ph - elektronnye preprinty
    Sm. takzhe:
    Vse publikacii na tu zhe temu >>

    Ocenka: 2.5 [golosov: 31]
     
    O reitinge
    Versiya dlya pechati Raspechatat'

    Astrometriya - Astronomicheskie instrumenty - Astronomicheskoe obrazovanie - Astrofizika - Istoriya astronomii - Kosmonavtika, issledovanie kosmosa - Lyubitel'skaya astronomiya - Planety i Solnechnaya sistema - Solnce


    Astronet | Nauchnaya set' | GAISh MGU | Poisk po MGU | O proekte | Avtoram

    Kommentarii, voprosy? Pishite: info@astronet.ru ili syuda

    Rambler's Top100 Yandeks citirovaniya