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Opros ob ideal'nom astrosaite na forume Zvezdocheta
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Soderzhanie i bystryi perehod k razdelam obzora
Karta Vselennoi
Kosmologicheskie parametry soglasno SDSS i WMAP
Putanica s rasshireniem: chastoe neponimanie kosmologicheskih gorizontov i sverhsvetovoe rasshirenie Vselennoi
Vspyshki v blizhnem IK ot akkreciruemogo gaza vokrug sverhmassivnoi chernoi dyry v centre Galaktiki
Otdel'nye stat'i
Iz razdela physics
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.): Poleznye astronomicheskie ssylki. Korotkoe esse ob elektronnyh preprintah. Obzornye stat'i v astro-ph s 2001 g.
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Referaty otdel'nyh statei
Authors: B. McKernan et al. Comments: 4 pages, uses emulateapj.cls, ApJL (accepted) Okolo poloviny barionov vo Vselennoi dolzhny nahoditsya v teplom ili goryachem gaze v mezhgalakticheskom prostranstve. Obnaruzhit' eto veshestvo ochen' nelegko. Ono dolzhno proyavlyat' sebya v vide detalei v spektrah dalekih galaktik. Avtory etoi raboty izuchali rentgenovskii spektr seifertovskoi galaktiki, poluchennyi na Chandre. Issledovateli v samom dele obnaruzhili sil'nuyu spektral'nuyu detal', kotoruyu oni svyazyvayut s teplym/goryachim mezhgalakticheskim gazom. Eto nablyudenie podtverzhdaet raschety, soglasno kotorym sushestvuyut volokna takogo gaza. Himicheskii sostav eto veshestva mozhet zametno otlichat'sya ot solnechnogo.
Authors: Hideki Madokoro, Tetsuya Shimizu, Yuko Motizuki Comments: 5 pages, including 4 figures, to be published in the proceedings of IAU Colloquium 192, `SUPERNOVAE (10 years of SN1993J)'', Valencia, Spain, eds. J.M. Marcaide and K.W. Weiler (Springer Verlag) V fizike vzryva sverhnovoi est' eshe ochen' i ochen' mnogo neponyatnogo. V naibolee prorabotannoi na segodnyashnii den' modeli sbros obolochki proishodit za schet moshnogo potoka neitrino. Odnako, poka v raschetah ne udaetsya poluchit' nuzhnuyu energetiku vzryva pri dannoi neitrinnoi svetimosti. Yaponskie uchenye rassmatrivali zavisimost' energii vzryva ot parametrov fluktuacii neitrinnogo potoka. Pust' u nas zadana polnaya neitrinnaya svetimost'. No pust' my mozhem zadavat' nebol'shie uglovye fluktuacii potoka. Okazyvaetsya, chto eto mozhet pomoch' v reshenii problemy sbrosa obolochki! Poka raschety provedeny dlya dostatochno prostoi modeli. No rezul'taty obnadezhivayut. Neobhodimy bolee detal'nye raschety.
Authors: Joeri van Leeuwen, Frank Verbunt Comments: 4 pages, 2 figures. To appear in "Young Neutron Stars and Their Environments" (IAU Symposium 218, ASP Conference Proceedings), eds F. Camilo and B. M. Gaensler Kak izvestno, neitronnye zvezdy - eto svoeobraznye astrofizicheskie laboratorii, gde veshestvo nahoditsya v ekstremal'nom sostoyanii. Poetomu protekanie razlichnyh fizicheskih processov v etih kompaktnyh ob'ektah predstavlyaet obshii interes. Odnim iz takih processov yavlyaetsya evolyuciya magnitnogo polya. Neitronnye zvezdy obladayut samymi sil'nymi magnitnymi polyami vo Vselennoi (u naibolee zamagnichennyh iz izvestnyh segodnya ob'ektov oni prevoshodyat 1014 Gs). My ne znaem, kak takie polya generiruyutsya (prostym szhatiem s sohraneniem magnitnogo potoka tut ne oboitis'), i ne znaem, kak oni izmenyayutsya so vremenem. Sobstvenno, izmenenie mozhet byt' odno - polya mogut zatuhat'. Polya porozhdayutsya tokami, kotorye tak ili inache dolzhny umen'shat'sya. Vopros v tom naskol'ko bystro i sushestvenno. Pryamye dannye nablyudenii ne dayut odnoznachnogo otveta o povedenii magnitnogo polya neitronnyh zvezd. Naprimer, molodye pul'sary imeyut neskol'ko bOl'shie polya, chem bolee starye istochniki etogo tipa. No statistika nevelika, a krome togo mogut byt' vazhny raznoobraznye effekty selekcii. Poetomu obychno primenyaetsya modelirovanie - populyacionnyi sintez. I tut tozhe raznye gruppy poluchayut raznye rezul'taty. Avtory dannoi zametki polemiziruyut s temi, kto govorit o zametnom umen'shenii magnitnogo polya za vremya poryadka 10 millionov let. Kak pokazano v etoi rabote, vvedenie dopolnitel'nogo parametra - zavisimosti shiriny puchka izlucheniya ot perioda vrasheniya neitronnoi zvezdy - pozvolyaet opisat' dannye nablyudenii bez zatuhaniya polya. Takaya zavisimost' imeet pod soboi horoshuyu osnovu, poetomu k rezul'tatam issledovaniya stoit otnestis' ser'ezno.
Authors: E. S. Rykoff et al. Comments: Five pages, four figures, uses emulateapj class file. Accepted to Astrophysical Journal Letters Poka udalos' zaregistrirovat' lish' neskol'ko rannih opticheskih oreolov (poslesvechenii) kosmicheskih gamma-vspleskov. Odnako dazhe eta malen'kaya vyborka uzhe pokazyvaet raznoobrazie svoistv. Avtory raboty opisyvayut nablyudeniya takih yavlenii, a takzhe obsuzhdayut vozmozhnuyu interpretaciyu razlichii. V predlagaemoi imi modeli, gde gamma-vsplesk svyazan s kollapsom massivnoi zvezdy, klyuchevuyu rol' igraet zvezdnyi veter. Opticheskoe poslesvechenie opredelyaetsya strukturoi, obrazovannoi zvezdnym vetrom v techenie zhizni zvezdy.
Authors: D. J. Thompson Comments: To appear in "Young Neutron Stars and Their Environments" (IAU Symposium 218, ASP Conference Proceedings), eds F. Camilo and B. M. Gaensler Sovremennaya astronomiya - vsevolnovaya. Lyuboi ob'ekt stremyatsya izuchit' v raznyh diapazonah spektra. Pul'sary - ne isklyuchenie.
Profili impul'sov semi pul'sarov v raznyh diapazonah. Na nizhnei osi ukazan period vrasheniya neitronnoi zvezdy v millisekundah. V blizhaishie neskol'ko let budet zapusheno neskol'ko kosmicheskih apparatov, kotorye v chastnosti smogut nablyudat' gamma-izluchenie ot odinochnyh neitronnyh zvezd. Ob etom i rasskkazyvaetsya v obzore.
Authors: J. Richard Gott III et al. Comments: Additional material accessible on the web at: http://www.astro.princeton.edu/~mjuric/universe/ Vot tak! Ni bol'she, ni men'she. Karta prostiraetsya ot okrestnostei nashei planety do kosmicheskogo reliktovogo izlucheniya (po suti imeetsya vvidu "poverhnost' poslednego rasseyaniya", samo-to izluchenie est' i vokrug nas) i vklyuchaet v sebya novye dannye (poyas Koipera, SDSS etc.). Chitaite ob etom otdel'nuyu ANKU.
Authors: Anthony Aguirre Comments: 10 pages, to appear in the proceedings of the IAU Symposium 220 "Dark matter in galaxies", eds. S. Ryder, D.J. Pisano, M. Walker and K. Freeman Avtor rassmatrivaet razlichnye proveryaemye al'ternativy temnoi materii v galaktikah i skopleniyah galaktik. Pokazano, chto mnogie iz nih mogut byt' blagopoluchno otbrosheny. Osoboe vnimanie udeleno MOND-MODified Newtonian Dynamics.
Authors: J.M. Rathborne, M.G. Burton Comments: 8 pages, 1 figure (low resolution), To appear in the IAU Highlights of Astronomy, Volume 13, Edited by O. Engvold & M. Burton, Published by the Astronomical Society of the Pacific SPIREX (South Pole InfraRed EXplorer Telescope) - nebol'shoi 60-santimetrovyi teleskop, ustanovlennyi v 1994 g. v Antarktide na stancii Amundsen-Skott. Odnoi iz zadach instrumenta bylo pokazat' na praktike, chto Yuzhnyi polyus yavlyaetsya kraine udobnoi ploshadkoi dlya nablyudenii v IK diapazone. Deistvitel'no, mnogie uchastki v Antarktide nahodyatsya dostatochno vysoko nad urovnem morya, a krome togo tam ochen' holodno. Avtory privodyat rezul'taty nablyudenii na SPIREX. Konechno, malen'kii instrument ne mozhet tyagat'sya s 8-10-metrovymi gigantami. No ideya sostoit v osnovnom v illyustracii astroklimaticheskih vozmozhnostei Antarktidy dlya nuzhd infrakrasnoi astronomii.
Authors: J. M. Miller et al. Comments: 8 pages, 6 figres, 3 in color, uses emulateapj.sty and apjfonts.sty submitted to ApJ Napomnim, chto eshe neskol'ko let nazad elementom standartnoi kartiny byli tri tipa chernyh dyr: pervichnye (naibolee mnogochislennye na segodnyashnii den' dolzhny imet' massu poryadka 1015 g.), ostavshiesya ot rannei epohi zhizni Vselennoi, zvezdnye (massoi poryadka 5-10 mass Solnca), obrazovavshiesya iz massivnyh zvezd v rezul'tate kollapsa, i sverhmassivnye (s massami ot 106 do 1010 mass Solnca). V poslednee vremya poyavlyayutsya razlichnye ukazaniya na sushestvovanie chernyh dyr promezhutochnyh mass v sotni mass Solnca. Odnimi iz kandidatov v takie ob'ekty yavlyayutsya t.n. sverhmoshnye (Ultraluminous) rentgenovskie istochniki. V dannoi rabote avtory issledovali spektr odnogo iz takih istochnikov. Odna iz komponent spektra interpretiruetsya kak vklad holodnogo (po merkam akkrecii na kompaktnye ob'ekty) diska s temperaturoi 0.17-0.29 keV. Masshtabirovanie svoistv diskov izvestnyh galakticheskih kandidatov v chernye dyry privodit k sleduyushemu rezul'tatu: my vidim akkreciyu na chernuyu dyru s massoi poryadka 1000 mass Solnca. Konechno, eto model'nyi rezul'tat. Neobhodimy dal'neishie issledovaniya. No tak ili inache, a svoistva istochnika X-9 v M81 yavlyayutsya ser'eznym argumentom. Storonnikam anizotropnogo izlucheniya pridetsya potruditsya, chtoby ob'yasnit' dannye nablyudeniya bez privlecheniya stol' massivnoi chernoi dyry.
Authors: Johnny S. T. Ng Comments: 12 pages, To be published in the proceedings of the Joint 28th ICFA Workshop on Quantum Aspects of Beam Physics, Hiroshima, Japan, Jan. 7-11, 2003 Vselennuyu ne zrya nazyvayut "uskoritelem dlya bednyh". Priroda sama predostavlyaet nam chasticy s energiyami do 1020 eV (i dazhe vyshe), kotorye dazhe v mechtah nedostizhimy dlya laboratornoi fiziki. No vse ponimayut preimushestva obychnogo "nastol'nogo" eksperimenta pered astronomicheskimi nablyudeniyami. Eto tochnost', kontroliruemost' i t.p. Poetomu interesno obsudit' takoi povorot sobytii: chto sovremennaya uskoritel'naya fizika mozhet dat' astrofizike. Krome kalibrovki priborov i t.p. avtor obsuzhdaet neskol'ko vozmozhnyh eksperimentov. Odin iz nih - eto elektron-pozitronnye puchki v kachestve relyativistskoi plazmy. Ideya v tom, chtoby smeshat' elektronnyi i pozitronnyi puchki, kotorye dadut potok, analogichnyi relyativistskoi e+e-plazme. Otmetim rabotu "Supernova Science at Spallation Neutron Sources", v kotoroi obsuzhdaetsya rol' laboratornyh eksperimentov dlya ponimaniya fiziki sverhnovyh.
Authors: T. Oosterloo et al. Comments: To appear in the proceedings of the IAU Symposium #217, Recycling Intergalactic and Interstellar Matter, eds. P.-A. Duc, J. Braine, and E. Brinks, 6 pages with low resolution figures. The full paper with high resolution images can be downloaded from http://www.astron.nl/~morganti/Papers/cloud.ps.gz My uzhe pisali o prizrakah galaktik. Vot eshe odin interesnyi primer takih prividenii. Avtory obnaruzhili dva nebol'shih oblaka ionizovannogo vodoroda (HII) v bednoi gruppe galaktik vokrug NGC 1490. Oblasti HII lezhat kak minimum v 100 kpk ot blizhaishei opticheskoi galaktiki. Zato oni svyazany s oblastyami neitral'nogo vodoroda (HI), kotorye obrazuyut cepochku dlinoi 500 kpk. Metallichnost' etih oblakov blizka k solnechnoi, chto ne pozvolyaet govorit' ob ih pervichnoi prirode. Naibolee veroyatno, chto eto ostatki galaktiki, kotoraya byla razrushena prilivnymi silami. Nalichie oblastei ionizacii (HII) govorit o tom, chto imeet mesto process zvezdoobrazovaniya. Avtory polagayut, chto vokrug vzaimodeistvuyushih galaktik mozhet byt' mnogo takih oblakov neitral'nogo vodoroda. A my pozvolim sebe pofantazirovat' o planete na orbite vokrug zvezdy, obrazovavsheisya v takom oblake v mezhgalakticheskom prostranstve. Predstav'te, nebo fakticheski bez zvezd, zato "visit" galaktika, kotoraya svoim prilivnym vozdeistviem vse eto i ustroila... Otmetim, v zaklyuchenie, chto poyavilas' i drugaya stat'ya "Discovery of Intergalactic HII Regions", gde takzhe govoritsya ob otkrytii vnegalakticheskih oblastei HII.
Authors: Ofer Lahav, Yasushi Suto Comments: 79 pages, 29 figures, invited review article submitted to Living Reviews in Relativity, http://relativity.livingreviews.org Bol'shie obzory krasnyh smeshenii galaktik - vazhnoe dostizhenie sovremennoi nablyudatel'noi astronomii. V chastnosti, eto vazhnyi instrument sovremennoi kosmologii. Imenno o etom, a takzhe o razvitii dannogo napravleniya issledovanii, i rasskazyvaetsya v obzore.
Authors: J. P. Mbelek, M. Michalski Comments: 9 pages, no figure Anomal'noe uskorenie sputnikov Pioner do sih por ne daet pokoya mnogim issledovatelyam. Chto tol'ko ne predlagali dlya ob'yasneniya effekta. V dannoi rabote rassmatrivaetsya vopros ob ob'yasnenii effekta bez privlecheniya ekzotiki. Raznicu v povedenii Pionera - 10 i Pionera - 11 udaetsya ob'yasnit' bez novoi fiziki (effekt okazalsya svyazannym s vrasheniem apparatov). A vot sam effekt anomal'nogo uskoreniya vozmozhno taki trebuet ekzotiku. (Blagodarim S.I. Blinnikova za kommentarii po etoi rabote.)
Authors: A. I. Ibrahim et al. Comments: Submitted to ApJL; 4 pages; 4 figures Sobstvenno otkryt novyi rentgenovskii pul'sar s periodom 5.54 sekundy. Period uvelichivaetsya s tempom poryadka 10-11 s/s. Esli eto tormozhenie po magnito-dipol'noi formule, to pole poluchaetsya 3 1014 Gs. Eto magnitarnoe pole. Krome togo, net nikakih sledov vtorogo kompan'ona. Vse vmeste delaet ob'ekt klassicheskim anomal'nym rentgenovskim pul'sarom. Istochnik byl naiden takzhe i v arhivnyh dannyh. No togda on byl gorazdo slabee. Eto oznachaet, chto mozhet byt' dva sostoyaniya anomal'nogo pul'sara: aktivnoe i spokoinoe. A eto, v svoyu ochered', oznachaet, chto mnogo magnitarov mozhet skryvat'sya ot nas.
Authors: L. Clewley et al. Comments: 2 pages, 1 figure, to appear in the proceedings of the IAU Symposium 220: "Dark matter in galaxies", eds. S. Ryder, D.J. Pisano, M. Walker and K. Freeman, Sydney, July 2003, to be published in the ASP conference series Vo mnogom vopros "gde granica nashei Galaktiki?" pohozh na vopros "gde granica Solnechnoi sistemy?". Na vtoroi mnogie otvechayut "za orbitoi Plutona", chto sovershenno neverno. Tochno takzhe klassicheskaya kartinka nashei Galaktiki, obryvayushayasya gde-to na 15-20 kpk ot centra ne sovsem verna. Pokuda est' zvezdy (pust' i nemnogchislennye) ili voobshe chto-to, chto vrashaetsya vokrug Mlechnogo Puti (t.e. gravitacionno s nim svyazano v, skazhem tak, podchinennom sostoyanii) i ne yavlyaetsya otdel'noi galaktikoi (tipa karlikovyh chlenov Mestnoi gruppy), to eto eshe nash Zvezdnyi Dom. Samye dalekie zvezdy sostavlyayut t.n. galo galaktiki. I ih mozhno prosledit' na rasstoyaniya v 100-200 kpk. Avtory ispol'zovali dannye Sloanovskogo obzora (SDSS) po golubym zvezdam gorizontal'noi vetvi (BHB - blue horizontal branch). Blagodarya etim ob'ektam udalos' "propisat'" nashu Galaktiku do rasstoyanii v 130 kpk. Massa Mlechnogo Puti okazyvaetsya ravnoi 1.7(+3 -0.6) 1012 mass Solnca. Rabota prodolzhaetsya. V budushem ozhidaetsya sushestvennoe snizhenie neopredelennosti v opredelenii massy.
Authors: M. Livio, J. E. Pringle Comments: 4 pages Imeyushiesya dannye po ekzoplanetam govoryat o nalichii chetkoi korrelyacii mezhdu veroyatnost'yu uvidet' planetu i metallichnost'yu zvezdy. Mozhno bylo by polagat', chto eto effekt selekcii, svyazannyi vot s chem. Sovremennye metodiki obnaruzhivayut massivnye planety na blizkih orbitah (goryachie yupitery). Polagayut, chto planety migrirovali na eti orbity s bolee dalekih. Znachit, mozhno spekulirovat' o korrelyacii metallichnost'-migraciya. Avtory dannoi raboty vnimatel'no issledovali takuyu vozmozhnost' i ne nashli nikakih osnovanii v pol'zu dannoi gipotezy. Stalo byt', zaklyuchayut oni, est' real'naya korrelyaciya mezhdu metallichnost'yu i planetami.
Authors: Junichiro Makino et al. Comments: 25 pages, Accepted for publication in PASJ, scheduled to appear in Vol.55, No. 6 Daetsya obzor novoi versii parallel'nyh superkomp'yuterov serii GRAPE (GRAvity piPE) dlya modelirovaniya metodom mnogih tel, aktivno primenyayushimsya v astrofizike (struktura i vzaimodeistvie galaktik, zvezdnye skopleniya, krupnomasshtabnaya struktura, ustoichivost' i formirovanie planetnyh sistem i t.p.). Seriya nachalas' v nachale 90-h godov i, razumeetsya, moshnost' komp'yuterov bystro rosla. Komp'yutery GRAPE-3 i -5 proizvodilis' dazhe malymi seriyami, chto pozvolilo sdelat' ih ne ochen' dorogimi (t.e. dostupnymi bol'shinstvu krupnyh universitetov, gde byli sootvetstvuyushie gruppy issledovatelei). GRAPE-6 imeet 2048 processorov. Maksimal'naya skorost' - 64 Teraflopa. Stat'ya budet bezuslovno interesna vsem, kto interesuetsya chislennymi metodami, komp'yuternym modelirovanie i t.p.
Authors: Wolfgang Seidel Comments: 7 pages, Proceedings Physics in Collision, Zeuthen, Germany, 2003 Ochen' korotkii obzor po popytkam neposredstvennoi (laboratornoi) registracii chastic temnoi materii. Po suti sam obzor zanimaet menee 5 stranic, gde perechisleny osnovnye tipy detektorov i privedeny primery deistvuyushih (ili uzhe otrabotavshih) ustanovok.
Authors: Jordi Miralda-Escude, Juna A. Kollmeier Comments: 21 pages, submitted to ApJ Kak my uzhe pisali, sushestvuet problema, kak bystro sozdat' sverhmassivnye chernye dyry v yadrah galaktik. Mehanizm dolzhen ob'yasnyat' diapazon mass, skorost' obrazovaniya (est' dannye po massivnym dyram v epohu poyavleniya samyh pervyh galaktik), a takzhe razlichnye korrelyacii parametrov. V etoi stat'e avtory predlagayut takuyu model'. Vokrug chernoi dyry (kak sozdat' "zachatochnuyu" chernuyu dyru v principe ponyatno) sushestvuet tonkii akkrecionnyi disk. Zvezdy iz central'noi chasti galaktiki dinamicheskim vzaimodeistviem vybrasyvayutsya na vysokie vytyanutye orbity. Sootvetstvenno, zatem oni neskol'ko raz peresekayut disk v svoem vrashenii vokrug galakticheskogo centra. Pri kazhdom takom peresechenii zvezda teryaet uglovoi moment, i nakonec "vlivaetsya" v disk. Avtory obsuzhdayut dostoinstva i nedostatki modeli, i predlagayut nablyudatel'nye testy dlya proverki bazovah predpolozhenii i osnovnyh predskazanii scenariya.
Authors: Matt Visser, David L. Wiltshire Comments: 19 pages, 5 figures; uses iopart.cls, setstack.sty Nedavno v SMI (vklyuchaya Scientific American) proshla novost' (podannaya v neskol'ko preuvelichennom klyuche) o rabote Mazura i Mottoly po al'ternative chernym dyram. Avtory predlozhili model', v kotoroi blagodarya fazovomu perehodu v sostoyanie ves'ma specificheskogo kondensata obrazuetsya ob'ekt bez singulyarnosti, gorizonta sobytii i t.p. Takzhe avtory polagayut, chto oni reshili tem samym problemu bol'shoi entropii chernyh dyr. Sami Mazur i Mottola rassmotreli lish' teplovuyu ustoichivost' naidennogo imi resheniya. V dannoi rabote Visser i Viltshir rassmatrivayut dinamicheskuyu ustoichivost' resheniya, podobnogo poluchennomu Mazurom i Motolloi.
Authors: M. Tegmark et al. Comments: SDSS data and ppt figures available at http://www.hep.upenn.edu/~max/sdsspars.html My mnogo raz pisali ob opredelenii kosmologicheskih parametrov po dannym poslednih eksperimentov, vklyuchaya Sloanovskii cifrovoi obzor neba (SDSS) i sputnik WMAP, izuchayushii reliktovyi fon. Tegmark i soavtory iz komand SDSS i WMAP predstavlyayut po-vidimomu naibolee polnoe na segodnyashnii den' issledovanie.
Ne budem vdavat'sya v detali - oni privedeny v stat'e (a takzhe v
soputstvuyushih rabotah, o kotoryh chut' nizhe).
Privedem rezul'taty: Avtory detal'no opisyvayut parametry, modeli, kotorye oni ispol'zuyut i t.p., soprovozhdaya eto ponyatnymi illyustraciyami. V otdel'noi stat'e "The 3D power spectrum of galaxies from the SDSS" opisyvayutsya rezul'taty Sloanovskogo obzora po issledovaniyu krupnomasshtabnoi struktury na baze izmerenii 205,443 galaktik. Opyat' zhe vnimatel'no issleduyutsya vozmozhnye istochniki oshibok i neopredelennostei. Eto bol'shaya stat'ya, soderzhashaya 40 risunkov. odin iz kotoryh my privodim.
Na risunke privedeno raspredelenie >67000 galaktik vblizi ekvatorial'noi ploskosti. Cvet kodiruet absolyutnuyu zvezdnuyu velichinu. Upomyanem zdes' zhe stat'yu Bonda i dr. "Cosmic microwave background snapshots: pre-WMAP and post-WMAP". V nei, kak yasno iz nazvaniya, rech' idet o nablyudeniyah mikrovolnovogo (reliktovogo) fona do i posle WMAP. Po suti eto obzor. Avtory takzhe vyvodyat osnovnye kosmologicheskie parametry. Vozmozhno, ne lishne upomyantu' i rabotu "Morphology of Mock SDSS Catalogues", v kotoroi dannye SDSS ispol'zuyutsya dlya izucheniya sverhskoplenii. Vazhnym ob'edinyayushim momentom vseh etih rabot yavlyaetsya sozdanie soglasovannoi kosmologicheskoi kartiny (sm. takzhe ANKU "Karta Vselennoi").
Authors: F. Combes, A.-L. Melchior Comments: 2 pages, 2 figures, contribution in Scientific Highlights, SF2A-2003, to be published by EDP-Sciences Korotkii otchet o hode rabot nad interesnym proektom. Avotry postavili svoei zadachei s pomosh'yu chislennogo modelirovaniya poluchit' biblioteku slivayushihsya galaktik. Kak horosho izvestno, vzaimodeistvie galaktik mozhet porozhdat' ves'ma prichudlivye konfiguracii. Bylo by interesno zaranee imet' nabor simulyacii. Dlya togo, chtoby eto davalo otdachu, nuzhno imet' okolo 1000 smodelirovannyh sliyanii. Bol'shaya rabota!
Authors: V. Antonuccio-Delogu, U. Becciani, D. Ferro Comments: 29 pages, 4 figures. Code included in CPC program library Catalogue identifier: ADSC. Comput. Phys. Commun. 155(2003)159 Sushestvuet dostatochno mnogo otkrytyh kodov dlya samyh razlichnyh celei. V tom chisle i dlya kosmologicheskogo modelirovaniya. V dannoi stat'e avtory predstavlyayut opisanie programmy FLY. Rabota, razumeetsya, ochen' tehnicheskaya, no budet interesna tem, kto interesuetsya chislennym modelirovaniem.
Authors: J.-Ch. Hamilton, A. Beno\^{\i}t and the Archeops Collaboration Comments: 8 pages, 6 figures, to appear in C.R. Physique Opisany rezul'taty poslednego poleta balonnogo eksperimenta Archeops po izmereniyu mikrovolnovogo izlucheniya. Krome, estestvenno, kosmologicheskih rezul'tatov, opisany i drugie. Osobyi interes predstavlyaet podrobnaya karta diffuznogo submillimetrovogo izlucheniya v ploskosti nashei Galaktiki (napomnim, chto pri postroenii polnoi karty reliktovogo fona prihoditsya vychitat' vklad Galaktiki, a eto sovsem neprostoe delo).
Karta Galaktiki na volne 353 GGc.
Authors: D.J. Price, J.J. Monaghan Comments: 16 pages, 7 figures, accepted to MNRAS Dve stat'i (vtoraya "Smoothed Particle Magnetohydrodynamics II. Variational principles and variable smoothing length terms"), posvyashennye modelirovaniyu metodom sglazhennyh chastic (Smoothed Particle Hydrodynamics (SPH)). Predlozhen novyi algoritm, kotoryi proveren mnozhestvom odnomernyh testov, predstavlennymi v etih dvuh rabotah. Predpolagaetsya, chto algoritm budet kraine polezen v astrofizicheskih prilozheniyah (vklyuchaya neideal'nuyu MGD).
Authors: G. Nelemans Comments: Invited talk to appear in "The Astrophysics of Gravitational Wave Sources" (Maryland, April 2003), AIP in press, J. Centrella (ed) Dvoinye sistemy yavlyayutsya odnimi iz naibolee ochevidnyh kandidatov v istochniki gravitacionnyh voln (sm. takzhe obzor v UFN na russkom yazyke. Ssylka na spisok obzorov v levoi kolonke). Avtor rassmatrivaet v osnovnom nizkochastotnoe izluchenie, kotoroe smozhet registrirovat' kosmicheskii interferometr LISA (spisok ssylok na stranicy missii takzhe v levoi kolonke). Obsuzhdaetsya vozmozhnost' obnaruzheniya istochnikov LISA v elektromagnitnom diapazone, a takzhe prilozheniya k evolyucii dvoinyh sistem.
Authors: Peter Erwin Comments: LaTeX, 25 pages, 6 EPS figures. Submitted to Astronomy & Astrophysics. Version with full-resolution figures available at http://www.iac.es/galeria/erwin/research/ Katalog iz 67 galaktik s interesnoi morfologiei. V stat'e est' lyubopytnye illyustracii, kotorye pokazyvayut, kak vyglyadyat dvoinye peremychki (bary), i kak raznye struktury maskiruyutsya pod dvoinye bary.
Authors: Gianluca Calcagni Comments: 13 pages, to be published in JCAP Esli vy pridumali "sumasshedshuyu" shemu miroustroistva, to vam srazu nado zadumat'sya nad vozmozhnost'yu proverki vashei teorii. Prichem vazhno ne tol'ko, chtoby vasha teoriya ob'yasnyala vse to, chto i drugie. Vazhno naiti kriticheskii test: chto smoglo by razdelit' proyavleniya raznyh struktur. V etoi rabote avtor rassmatrivaet odin iz variantov brannogo mira Randall-Sandram. Pokazano, kak budushie eksperimenty smogut razlichit' zhivem li my v sootvetstvuyushem mire bran ili net.
Authors: Tamara M. Davis, Charles H. Lineweaver Comments: To appear in Publications of the Astronomical Society of Australia, 26 pages (preprint format), 6 figures Ochen' interesnaya i vazhnaya stat'ya! Ona soderzhit "pedagogicheskii" razbor shiroko rasprostranennyh zabluzhdenii otnositel'no rasshireniya Vselennoi. Rasshirenie Vselennoi - yavlenie nastol'ko neobychnoe i strannoe, chto tut legko zaputat'sya. Korotkii vopros kolleg pokazal, chto v golovah astrofizikov i pravda sushestvuet putanica, opisannaya v stat'e. V pervuyu ochered' rech' idet o voprose: "Mozhno li nablyudat' galaktiki, udalyayushiesya ot nas bystree skorosti sveta?" Pravil'nyi otvet - "da". Nado pokayatsya, chto i my vnesli vklad v rasprostranenie zabluzhdenii. Uspokaivaet lish' privedennyi v stat'e spisok, gde perechisleny naibolee "gromkie" ssylki (vklyuchaya knigi i stat'i Devisa, Liddla i dr.), gde takzhe govoritsya o principial'noi nevozmozhnosti nablyudeniya galaktik, ch'ya skorost' udaleniya ot nas (svyazannaya s rasshireniem Vselennoi) pevyshaet skorost' sveta. Ochen' sovetuem prochest' i razobrat'sya!
Authors: R. Genzel et al. Comments: 5 pages, 3 figures to appear in the Oct 30 issue of Nature Chernaya dyra v centre nashei Galaktiki ochen' "tihaya". Ee aktivnost' yavlyaetsya chrezvychaino nizkoi vo vseh diapazonah spektra. Poetomu, lyuboe novoe obnaruzhennoe proyavlenie yavlyaetsya kraine vazhnym i interesnym. Gruppa avtorov, kotorye uzhe horosho izvestny nashi chitatelyam po ih predydushim rabotam, posvyashennym centru Galaktiki, raportuet ob otkrytii vspyshek v blizhnem infrakrasnom diapazone. Vspyshki nablyudalis' v neposredstvennoi blizosti (neskol'ko millisekund dugi) ot chernoi dyry. U dvuh vspyshek byla otmechena periodichnost' s harakternym vremenem okolo 17 minut. Esli eto svyazano s vrasheniem gaza vokrug chernoi dyry, to my imeem delo s izlucheniem, voznikayushim v neposredstvennoi blizosti ot gorizonta. Krome togo, po etim dannym (esli interpretaciya verna) mozhno skazat', chto chernaya dyra ochen' bystro vrashaetsya.
Authors: Ilya G. Usoskin et al. Comments: 4 pages, LaTeX, revtex4 macros; Phys. Rev. Let., in press S pomosh'yu raznyh metodik mozhno pytat'sya vosstanovit' dannye o solnechnoi aktivnosti v proshlom. Naprimer, mozhno ispol'zovat' koncentraciyu berilliya-10 v arkticheskom i grenladskom l'dah. Avtory raboty smogli vosstanovit' chislo solnechnyh pyaten do serediny 9 veka. Prodelav eto, avtory zamechayut, chto aktivnost' Solnca v poslednie primerno 60 let byla anomal'no vysokoi.
Authors: Scott C. Noble Comments: 228 pages, 66 Postscript figures, Ph.D. Thesis, the University of Texas at Austin, uses utdiss2.sty v5 Dissertaciya posvyashena chislennomu modelirovaniya gravitacionnogo kollapsa. Tema arhislozhnaya i arhiaktual'naya.
Authors: Carsten Weidner, Pavel Kroupa Comments: MNRAS, accepted, 6 pages Ne nablyudayutsya zvezdy s massoi bolee primerno 150 mass Solnca. Tomu mozhet byt' dva ob'yasneniya: ili est' fundamental'nyi predel, t.e. zvezdy bolee vysokih mass ne obrazuyutsya, ili zhe prosto massivnye zvezdy slishkom redki, chtoby nam moglo povezti uvidet' takogo "zverya". Proanalizirovav dannye nablyudenii, avtory prihodyat k vyvodu o tom, chto predel vse-taki sushestvuet (esli tol'ko s funkciei mass ne proishodit chto-to sovsem udivitel'noe v diapazone samyh tyazhelyh zvezd).
Authors: John Ellis Comments: Opening Lecture at the 31st SLAC Summer Institute, July 2003: PSN L01, 19 pages latex, 9 eps figures, uses ssi.sty (included) Eto vvodnaya lekciya, kotoraya prizvana dostatochno populyarno obrisovat' vzaimosvyazi mezhdu fizikoi mikromira i kosmologiei. Na samom dele, eto skoree obzor po kosmologii, gde osoboe vnimanie udeleno problemam, kotorye mogut imet' otnoshenie k mikromiru (temnaya energiya, kosmicheskie luchi sverhvysokih energii i t.p.).
Sm. takzhe vtoruyu stat'yu Ellisa
"Cosmic Connections".
My budem starat'sya hotya by perechislit' interesnye (dlya shirokoi publiki)
stat'i, poyavivshiesya v razdele
physics
(vklyuchaya cross-listing).
Authors: E.P. Bonvin, S. T. Hatamian Comments: 15 pages
V poslednee vremya problema fiziki neitrino stanovitsya vse bolee populyarnoi.
Avtory rassuzhdayut, kak nedorogim sposobom mozhno peredelat' sushestvuyushii
detektor, postroennyi dlya poiska raspada protona, v neitrinnuyu observatoriyu.
Delo v tom, ustanovka nahodtsya vblizi atomnogo reaktora, chto delaet ee
horoshei mishen'yu dlya issledovanii neitrinnyh oscillyacii.
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