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| 15.03.03. (vypusk N35) astro-ph za 10 - 15 marta 2003 goda: izbrannye stat'i |
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Authors: R.J. Vanderbei
Authors: R. Buras et al.
Authors: M. Bernardi
Authors: S.L.Bridle, O.Lahav, J.P.Ostriker, P.J.Steinhardt
Authors: A.M.Ghez et al. Commets: 7 pages, 5 figures (abridged abstract) Postroeny orbity eshe neskol'kih zvezd obrashayushihsya vokrug sverhmassivnoi chernoi dyry v centre nashei Galaktiki (predydushie postroeniya sm. zdes'.) Odna iz etih zvezd (S0-16) v 1999 godu proletala na rasstoyanie 60 AU ot chernoi dyry i imela v tot moment skorost' 9000 km/s. Na fotografii oblast' 1"x1" s centrom v Sgr A*.
Authors: R.J. Vanderbei Commets: 16 pages, 2 tables, 6 figures Predlozhen metod nahozhdeniya periodicheskih reshenii v probleme n-tel. S ego pomosh'yu naideny neskol'ko chastnyh reshenii dlya n=3, 4 i 5. Nekotorye iz nih (dlya n=4) pokazany na risunke.
Authors: E. V. Gotthelf Commets: 6 pages, 3 figures, 1 table, LaTex, emulateapj5.sty. To appear in the June 20, 2003 issue of the Astrophysical Journal Novye nablyudeniya trebuyut utochnenii modelei. Dannye Chandry, pozvolivshie podrobno izuchit' 9 krabopodobnyh pul'sarov i ih tumannosti, trebuyut peresmotra modeli rentgenovskih spektrov etih ob'ektov. Vo mnogom eto svyazano s tem, chto predydushie nablyudeniya ne mogli razdelit' spektry samogo pul'sara i tumannosti (iz-za nizkogo uglovogo razresheniya). V stat'e predstavleny rezul'taty popytki postroeniya novoi fenomenologicheskoi modeli.
Authors: R. Buras et al. Commets: 5 pages, PRL submitted; 3 eps figures, 1 colored, high-quality available upon request Na t.n. tehasskoi konferencii vo Florencii v dekabre poshlogo goda porazil kommentarii Virdzhinii Trimbl, chto v obshem-to problema vzryva sverhnovoi reshena Vusli, Viverom i dr. (plyus kak obychno ehidnyi kommentarii, chto esli vy ne otlichaete Vusli-Vivera ot Visli-Vuvera, to slishkom dolgo rabotaete v etoi oblasti). Po ee mneniyu, ostaetsya tol'ko uchityvat' tonkosti: pole, vrashenie, him.sostav i t.d. Odnako, ne vse tak prosto. Gruppa Yanki i dr. davno vyskazyvala pessimizm otnositel'no sushestvuyushih problem v fizike vzryva sverhnovoi, po ih mneniyu slishkom mnogoe zakladyvaetsya rukami. Vot novoe podtverzhdenie ih vzglyadov. Novye detal'nye dvumernye raschety s vrasheniem i bez ne dayut vzryva. Odnimi neitrino vrode kak ne oboitis'. Vozmozhno kritichen uchet magnitnyh polei ili kakoi-to ekzotiki. O neitrino v sverhnovyh sm. takzhe otdel'nuyu stat'yu toi zhe gruppy "Supernova neutrinos: Flavor-dependent fluxes and spectra" astro-ph/0303226.
Authors: Henry E. Kandrup et al. Bohn Commets: 16 pages plus 15 figures Dvoinaya sverhmassivnaya chernaya dyra mozhet zdorovo "peremeshat'" zvezdy v galaktike. Kakie stadii est' u etogo processa? Kakova zona vliyaniya dvoinoi chernoi dyry? Kakie nablyudayushiesya fenomeny mozhno ob'yasnit' v ramkah etoi modeli? Vot osnovnye temy dannogo obzora.
Authors: Pawan Kumar and Jonathan Granot Commets: 22 pages, 6 figures. Accepted for publication in ApJ (scheduled for the v590, June 20, 2003 issue) Avtory - obladateli horoshego relyativistskogo gidrodinamicheskogo koda, kotoryi pozvolyaet im schitat' processy v gamma-vspleskah. Poschitana ocherednaya model', posle chego pokazano, chto ee rezul'taty horosho opisyvayutsya prostym analiticheskim priblizheniem (no do vypolneniya raschetov vyskazat' takoe utverzhdenie bylo nel'zya).
Authors: M. Bernardi Commets: 12 pages, 5 figures. To appear in "Carnegie Observatories Astrophysics Series, Vol. 2: Measuring and Modeling the Universe", ed. W. L. Freedman Poslednie gody v astrofizike otmecheny vazhnym novshestvom: razvitie komp'yuternyh tehnologii pozvolilo provodit' massirovannye avtomaticheskie obzory neba v raznyh diapazonah. Nekotorye iz takih proektov svyazany s kosmologicheskimi issledovaniyami. Napomnim, chto s nablyudatel'noi tochki zreniya sovremennaya kosmologiya baziruetsya na: nablyudeniyah reliktovogo izlucheniya, nablyudeniyah razbeganiya galaktik, dannyh o pervichnom nukleosinteze, dannyh po krupnomasshtabnoi strukture. Prichem, v svyazi s vozmozhnost'yu dostatochno detal'nyh raschetov obrazovaniya struktury poslednii punkt stal gorazdo vazhnee, chem on byl 20-30 let nazad. V stat'e daetsya obzor rezul'tatov Sloanovskogo obzora po krupnomasshtabnoi strukture. S odnoi storony vse standartno: standartnaya ploskaya model' s kosmologicheskoi postoyannoi prekrasno vse opisyvaet. S drugoi - eto ne prosto novyi vazhnyi kusok dannyh, eto eshe i ochen' krasivo.
Authors: Angela V. Olinto et al. Commets: Proceedings of the International Workshopon Extremely High Energy Cosmic Rays, RIKEN, Japan Esli kto-to propustil... Dannye dvuh eksperimentov po kosmicheskim lucham sverhvysokih energii - AGASA i HiRes - ne sovpadayut drug s drugom. Komandy uspeli obmenyat'sya rezkimi stat'yami, posvyashennymi poisku problem v eksperimente-sopernike i ob'yasneniyu svoei pravoty. Na samom dele rashozhdenie ne stol' kritichno. Po vsei vidimosti prosto mala statistika. Etomu i posvyashena stat'ya.
Authors: S.L.Bridle, O.Lahav, J.P.Ostriker, P.J.Steinhardt Commets: 2 pages, 2 figures. See online journal version Dannye WMAP po nablyudeniyu anizotropii relikta vkupe s drugimi eksperimental'nymi dannymi povysili tochnost' opredeleniya kosmologicheskih parametrov primerno v 2 raza. Dostatochno li etogo, chtoby proverit' klyuchevye komponenty standartnoi kosmologicheskoi modeli? Na dvuh stranicah avtory pokazyvayut, chto net.
Authors: Jozef Klacka Avtor vyvel kovariantnye uravneniya dvizheniya chastic pyli proizvol'noi formy v kotoryh uchityvaetsya vliyanie vneshnei elektromagnitnoi radiacii i teplovogo izlucheniya samih chastic. Uravneniya vyrazheny cherez standartnye opticheskie parametry. [Ne ponyatno, zachem dlya pyli vyvodit' relyativistskoe uravnenie dvizheniya? Vprochem eto nikogda i nigde ne meshaet.]
Authors: J. G. Kirk and O. Skjaeraasen Commets: Accepted for publication in ApJ Vnutri svetovogo cilindra energiya vrasheniya pul'sara perenositsya prakticheski polnost'yu elektromagnitnym potokom (potokom Pointinga), eto vyvod vseh sovremenny teorii i modelei. A uzhe nedaleko za svetovym cilindrom eta energiya prakticheski polnost'yu okazyvaetsya zaklyuchennoi v potoke relyativistskih chastic (vzaimodeistvie kotoryh s veshestvom nablyudaetsya). Raspredelenie unosimoi energii mezhdu elektromagnitnym potokom i chasticami opisyvaetsya parametrom sigma. Polnoi modeli dannogo processa na segodnyashnii den' net.
Authors: Robert D. Mathieu Commets: 10 pages, 5 figures, conference proceedings V stat'e dan obzor nablyudatel'nyh rezul'tatov poslednih 10 let o vrashenii malomassivnyh zvezd eshe ne dostigshih glavnoi posledovatel'nosti. Obsuzhdayutsya vozmozhnye mehanizmy ih tormozheniya.
Authors: B. Tingley Commets: Accepted for publications by Astronomy and Astrophysics Navernoe nazvanie stat'i ne sovsem tochno - deistvitel'no rassmatrivayutsya neskol'ko algoritmov obnaruzheniya vnesolnechnyh planet, no tol'ko po ih prohozhdeniyu po disku zvezdy. Dana statisticheskaya ocenka effektivnosti metodov.
Authors: Peter Anninos et al. Commets: 29 pages, 15 figures, to appear in Astrophysical Journal Supplement Series Opisyvaetsya moguchii vychislitel'nyi kod. Stat'ya tehnicheskaya. Privodyatsya rezul'taty testovyh progonov, obsuzhdayutsya uravneniya i t.p. Budet interesno vsem, kto zanimaetsya matmodelirovaniem.
Authors: G.J. Qiao, K.J. Lee, H.G. Wang, R.X. Xu Commets: 4 pages, 1 figure, in the meeting on "Radio Pulsars", Crete 2002, in press Nesmotrya na to, chto pul'sary izvestny uzhe bolee 35 let, mehanizm ih izlucheniya do konca ne ponyat. Avtory stat'i predstavlyayut ocherednuyu popytku opisat' izluchenie pul'sarov ot radio do gamma diapazona v edinoi modeli. Dannaya stat'ya - eto materialy konferencii. potomu tut ochen' kratko, tezisno, perechisleny osnovnye cherty modeli. Osnovnuyu rol' v podhode avtorov stat'i igraet obratnoe komptonovskoe rasseyanie. Podgonkoi parametrov modeli im udaetsya opisat' impul'sy 7 horosho izuchennyh pul'sarov.
Authors: Igor A. Shovkovy, Paul J. Ellis Commets: 7 pages. Talk presented at 2002 International Workshop "On Strong Coupling Gauge Theories And Effective Field Theories" (SCGT 02), 10-13 December 2002, Nagoya, Japan V fizike neitronnyh zvezd ochen' vazhnoi i interesnoi zadachei yavlyaetsya raschet ih ohlazhdeniya. Delo v tom, chto s odnoi storony eta problema trebuet ponimaniya povedeniya veshestva v ekstremal'nyh usloviyah, s drugoi - eto mozhno proverit' v nablyudeniyah (sm., naprimer, raboty Sankt-Peterburgskoi gruppy i ih obzor v UFN). T.n. "strannye zvezdy" ohlazhdayutsya po-drugomu.... Ob etom avtory rasskazyvayut v obsuzhdaemoi stat'e. Eto ne obzor, odnako, mnogie vazhnye ssylki prisutstvuyut. Krome togo v statei "mnogo fiziki, malo formul". T.o. eta korotkaya zametka budet interesna fizikam.
Authors: Andrey V. Kravtsov Commets: submitted to ApJL, 5 pages, 3 figures, LaTeX (uses emulateapj5.sty) Zvezdoobrazovanie - process slozhnyi. Odnako, tam est' prostye zakonomernosti. naprimer, zakon Shmidta: poverhnostnaya plotnost' molodyh zvezd proporcional'na poverhnostnoi plotnosti mezhzvezdnogo gaza v nekotoroi stepeni (poverhnostnaya oznachaet "prosummirovannaya poperek diska"). Eta prostaya zavisimost' byla obnaruzhena bolee 40 let nazad. S teh por bylo mnogo popytok ee ob'yasnit'. I problema ne v tom, chto ob'yasneniya net, a v tom, chto ih mnogo! V dannoi rabote predstavleny rezul'taty chislennogo modelirovaniya, v kotoryh estestvennym obrazom voznikaet zakon Shmidta. Pravda, eto ne oznachaet, chto naideno ob'yasnenie. Odnako, mozhno sdelat' vazhnyi vyvod, chto zvezdoobrazovanie na bol'shim masshtabah opredelyaetsya sverhzvukovoi turbulentnost'yu, kotoraya svyazana s gravitacionnymi neistoichivostyami na bol'shih masshtabah, a ne obratnym vliyaniem zvezd ili teplovymi neistoichivostyami, kotorye sushestvuyut na nebol'shim masshtabah.
Author: Andrei Gruzinov (NYU) Commets: 4 pages, 3 figures Reshenie zadachi o sil'nom vzryve v veshestve so stepennym raspredeleniem plotnosti obladaet avtomodel'nost'yu. Dlya pokazatelya adiabaty 5/3 resheniya v srede s alpha<3 (alpha - pokazatel' stepeni v zavisimosti plotnosti ot radiusa) obladayut avtomodel'nost'yu I roda, pri alpha >3.26 - avtomodel'nost'yu II roda. V stat'e naideno reshenie dlya ostavshegosya intervala (3< alpha <3.26) i ego nel'zya otnesti ni k odnomu iz ukazannyh tipov.
Authors: Andrei Linde Commets: 8 pages, 4 figs., extended version of the talk given at the conference COSMO-01, September 4, 2001, Rovaniemi, Finland "Esli nel'zya, no ochen' hochetsya, to mozhno". Predstavlen klass modelei, gde plotnost' bol'she kriticheskoi. Avtor otmechaet, chto modeli maloprivlekatel'ny i trebuyut podgonki. T.o. predskazanie inflyacii o blizosti plotnosti k kriticheskoi ostaetsya v sile.
Authors: Klaus Maisinger, M.P. Hobson and A.N. Lasenby Commets: 21 pages, 20 figures, submitted to MNRAS Eta stat'ya budet polezna ne tol'ko astronomam. Tam est' i teoriya, i mnogo naglyadnyh primerov. Eto ne obzor, a skoree horoshee nebol'shoe uchebnoe posobie.
Authors: Roelof Bottema Commets: Accepted for publication in: Monthly Notices of the Royal Astron. Soc. The astro-ph copy has a few figures with degraded resolution. A copy with high quality graphics (4281 kb) can be downloaded from the kapteyn institute weg page at http://www.astro.rug.nl (Goto preprints and preprints 2003) Modelirovanie galaktik - neprostoe zanyatie. Dlya togo, chtoby poluchit' strukturu nedostatochno pol'zovat'sya tol'ko metodom mnogih tel, ili naoborot tol'ko gidrodinamikoi. V dannoi stat'e opisyvayutsya vychisleniya, vklyuchayushie v sebya zvezdy, gaz (s uchetom ohlazhdeniya i nagreva), zvezdoobrazovanie i sverhnovye (kotorye v svoyu ochered' vliyayut na gaz). V obshem: slozhno i interesno. Stat'ya bol'shaya (30 zhurnal'nyh stranic), zato s kartinkami....
Authors: Prasenjit Saha (QMW London), Liliya L.R. Williams (U Minnesota) Commets: 26 pages, incl. 15 figs; accepted to AJ; java applet available at http://ankh-morpork.maths.qmw.ac.uk/~saha/astron/lens/ Nablyudatel'nye harakteristiki kvazarov s neskol'kimi izobrazheniyami (iz-za gravitacionnogo linzirovaniya) obladayut celym ryadom model'no-nezavisimyh svoistv, kotorye mozhno vyvesti iz ochen' prostyh soobrazhenii. Eti ideyu illyustriruyutsya na celom ryade real'no nablyudaemyh sistem. Na saite avtora deistvuet java-applet.
Authors: James E. Taylor, Kavilan Moodley & J. M. Diego Commets: 5 pages, 3 figures; submitted to MNRAS Samoe moshnoe proyavleniem effekta Syunyaeva-Zel'dovicha mozhet nablyudat'sya pochti u "nashego poroga" - na galo galaktiki M31. Zona ponizhennoi yarkosti reliktovogo fona budet imet' razmer poryadka 10 gradusov. Takoi bol'shoi razmer ne uproshaet, a zatrudnyaet ee obnaruzhenie.
Authors: Max Pettini Commets: Lectures given at the XIII Canary Islands Winter School of Astrophysics, osmochemistry: The Melting Pot of Elements'. To be published by Cambridge University Press; 42 pages, 33 figures Bol'shoi material, gde v "pedagogicheskoi" forme izlozheny sovremennye dannye po nablyudeniyu obiliya elementov ot nashim okrestnostei do bol'shih krasnyh smeshenii. Konechno zhe, opisyvaetsya i teoretieskoe ponimanie etoi problemy.
Authors: M. Revnivtsev et al. (MPA, Garching, Germany; IKI, Moscow, Russia) Commets: Accepted for publication in Astronomy Letters Eto odna iz pervyh otechestvennyh statei (a mozhet byt' prosto pervaya), napisannaya po dannym zapushennogo v konce 2002 gody sputnika INTEGRAL. Zhestkii rentgenovskii IGR J16318-4848 otkryt s INTEGRALa, zatem ego udalos' obnaruzhit' v arhivnyh dannyh yaponskogo sputnika ASCA (1994), no tam on ne byl identificirovan. Istochnik obladaet sovershenno neobychnymi svoistvami - pohozhe on svetit cherez tolstyi sloi veshestva - ranee takogo nigde ne nablyudalos'. Pervaya predlozhennaya model' - akkreciruyushii iz zvezdnogo vetra istochnik v massivnoi dvoinoi sisteme.
Authors: Robert T. Fisher Commets: 40 pages, 7 figures Opisana poluempiricheskaya model' obrazovaniya dvoinyh sistem. Osnovnye orbital'nye parametry svyazany s parametrami turbulentnosti v materinskom molekulyarnom oblake. Kachestvenno avtoru udaetsya ob'yasnit' osnovnye svoistva raspredelenii dvoinyh po periodam i nekotorye drugie korrelyacii.
Authors: D. Eichler, Y. Lyubarsky, C. Thompson, P.Woods Commets: 8 pages, 1 fig. To appear in Proc. Marsala workshop "Pulsars, AXPs and SGRs observed with BeppoSAX and other observatories" "V mire skazok tozhe est' bulochki". U istochnikov myagkih povtoryayushihsya gamma-vspleskov tozhe est' rentgenovskie poslesvecheniya. Avtory pokazyvayut, kak etot fenomen nahodit svoe ob'yasnenie v ramkah naibolee populyarnyi na segodnyashnii den' magnitarnoi gipotezy.
Authors: Philippe Brax, Carsten van de Bruck Commets: 37 pages; invited topical review for Classical and Quantum Gravity; to appear Bol'shoi obzor s polutorasotnei ssylok. Bez formul v etom dele ne oboitis', no beglyi prosmotr pokazyvaet, chto mozhno prorvat'sya!
Arhiv statei, voshedshih v predydushie vypuski.
Razdely arhiva (s iyulya 2002 g.): Poleznye astronomicheskie ssylki. Obzornye stat'i v astro-ph s 2001 g. |
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