The R.A.P. Project (Reviews of Astro-Ph)
Chislennoe modelirovanie
(Arhiv Chislennoe modelirovanie: v.2, 2003,
v.1, 2002-2003)
Authors: William G. Hoover
Comments: 20 pages
Avtoru stat'i seichas 72 goda, a potomu on vpolne mozhet obozrevat' promezhutki vremeni poryadka poluveka. V osnovnom raboty avtora kasalis' modelirovaniya molekulyarnoi dinamiki, o chem on i vspominaet. Voobshe, interesno pochitat' biografiyu uchenogo ....
Kstati, na stranice avtora v otskanirovannom vide est' neskol'ko poleznyh knig po chislennomu modelirovaniyu.
Authors: F. Chris Fragile
Comments: 14 pages, invited review for VII Microquasar Workshop
Nebol'shoi, a potomu neizbezhno nepolnyi, obzor po modelirovaniyu struinyh istechenii ot chernyh dyr. Avtor rassmatrivaet imenno obrazovanie strui, v to vremya kak mnogie issledovaniya svyazany s ustoichivost'yu strui, ih proyavleniyami i tp. V rassmotrennyh modelyah dlya zapuska dzheta neobhodimo magnitnoe pole.
Authors: Julio F. Navarro et al.
Comments: Submitted to MNRAS
Avtory predstavlyayut rezul'taty proekta Aquarius po modelirovaniyu obrazovaniya galaktik. Formirovanie galaktik - eto, v pervuyu ochered', formirovanie galo temnogo veshestva. V predstavlyaemyh modelyah galo sostoit iz bolee chem milliarda chastic, a v nachal'nom modelirovanii uchastvovalo bolee 4 milliardov chastic (prosto ne vse v konce scheta vhodyat v sostav galo). Obnaruzheno nebol'shoe sistematicheskoe otklonenie ot teoreticheskih profilei Navarro, Frenka i Vaita, kotorye aktivno ispol'zuyutsya v raznyh modelyah (vse troe, kstati, vhodyat v chislo avtorov obsuzhdaemoi stat'i).
Authors: Sergei K. Godunov
Comments: 27 pages
Vsem chitat'! Godunov vspominaet o sozdanii godunovskih chislennyh shem, nazvannyh v ego chest'. Ochen' interesno!
Obsudit' v ZhZh-soobshestve
ru_astroph.
Obsudit' na Astroforume v
Nauchnoi panorame.
Authors: Elizabeth J. Tasker et al.
Comments: 18 pages, 15 figures. Accepted for publication in MNRAS
Avtory sravnivayut chetyre koda: Enzo, Flash, Gadget i Hydra. Dlya etogo oni reshayut s ih pomosh'yu nekotorye zadachi s izvestnymi resheniyami. Rech' ne idet o vyyavlenii "chempiona", prosto vazhno ponyat' kakie kody luchshe podhodyat dlya raznyh klassov zadach.
Authors: M. Trenti, P. Hut
Comments: 13 pages, invited refereed review for the Scholarpedia Encyclopedia of Astrophysics
Enciklopedicheskii obzor po odnomu iz samyh chasto ispol'zuemyh metodov v astrofizicheskom modelirovanii: metodu mnogih tel. Etim metodom izuchayut i solnechnuyu sistemu (ravno kak i drugie sistemy), i zvezdnye konglomeraty ot skoplenii do galaktik, i krupnomasshtabnoe raspredelenie samih galaktik.
Authors: K. von Braun et al.
Comments: To appear in the Proceedings of the 253rd IAU Symposium: "Transiting Planets", May 2008, Cambridge, MA. 4 pages, 2 figures
Opisana sluzhba (i baza dannyh) NStED (NASA/IPAC/MSC Star and Exoplanet Database). Privodyatsya dannye po 140 000 yarkim blizkim zvezdam, po izvestnym planetam i tp. Razumeetsya, baza budet rasti, osobenno posle zapuska novyh sputnikov, special'no prednaznachennyh dlya poiska ekzoplanet.
Authors: Luca Baiotti, Bruno Giacomazzo, Luciano Rezzolla
Comments: 33 pages, 29 figures, submitted to Phys. Rev. D
Avtory predstavlyayut novyi detal'nyi raschet sliyaniya dvuh neitronnyh zvezd. Predmet osobogo interesa avtorov ? kollaps v chernuyu dyru. V samom dele, obychno summarnaya massa dvuh neitronnyh zvezd prevoshodit predel ustoichivosti otnositel'no kollapsa v chernuyu dyru. Kollaps mozhet proishodit' srazu posle sliyaniya ili zhe s nekotoroi zaderzhkoi. Zaderzhka svyazana s tem, chto bystroe differencial'noe vrashenie mozhet kakoe-to vremya uderzhivat' ob'ekt ot shlopyvaniya.
Raschety takogo processa kraine slozhny, i dazhe predstavlyaemye rezul'taty daleki ot real'noi situacii. Avtory obsuzhdayut, kakovy mogut byt', naprimer, effekty magnitnyh polei, ne uchityvaemye v dannyh modelyah. Krome togo, poka bylo ispol'zovano dostatochno primitivnoe uravnenie sostoyaniya veshestva neitronnyh zvezd.
Authors: Antoine Petiteau et al.
Comments: 22 pages, Physical Review D 77, 023002 (2008) 11
Trenirovat'sya nado na koshkah. Ili na komp'yuternyh modelyah. Poetomu pri razrabotke krupnyh nauchnyh proektov raznye gruppy zanimayutsya roazrabotkoi komp'yuternyh simulyatorov ustanovki. V dannom sluchae rech' idet o kosmicheskom gravitacionno-volnovom detektore LISA.
Programma pozvolyaet rasschityvat' chuvstvitel'nost' detektora i signaly ot istochnikov s izvestnymi svoistvami. Programma nahoditsya v svobodnom dostupe.
Authors:
Comments:
Predstavlen kod dlya modelirovaniya sliyaniya galaktik i prochih interesnyh yavlenii, gde primenimo priblizhenie mnogih tel. Programma mozhet ispol'zovat'sya kak na obychnyh komp'yuterah, tak i na GRAPE. Yazyk - Fortran 95. Programma takzhe mozhet byt' ispol'zovana dlya issledovaniya kosmologicheskih zadach (t.e. mozhno vklyuchat' kosmologicheskoe rasshirenie).
Sm. takzhe vtoruyu stat'yu, posvyashennuyu etomu kodu: arxiv:0802.4253.
Authors: S. Rosswog, D.J. Price
Comments: 28 pages, 8 Figures; submitted to Springer Lecture Notes in Computational Science and Engineering
Avtory opisyvayut novyi metod chislennogo modelirovaniya, pozvolyayushii uchityvat' magnitnye polya pri trehmernyh raschetah samogravitiruyushih sistem.
Authors: F. K. Roepke
Comments: 10 pages, 1 figure; in "Modelling and Simulation in Science", Proceedings of the 6th International Workshop on Data Analysis in Astronomy "Livio Scarsi", Erice, Italy 15 - 22 April 2007 (World Scientific, 2008)
Inogda pri chislennom modelirovanii uchenye stalkivayutsya s zadachami, gde nado odinakovo podrobno propisyvat' ochen' raznye masshtaby. Eto oznachaet, chto ni o kakoi ravnomernoi setke rechi net. Bolee togo, inogda i neravnomernuyu setku prihoditsya dvigat', poskol'ku ob'ekt, rassmatrivaemyi v zadache, "dyshit". Horoshim primerom takih modelei yavlyaetsya vzryv sverhnovoi. Avtor dostatochno prostym, prozrachnym, yazykom opisyvaet osnovnye svoistva takih modelei.
Authors: Lucio Mayer, Fabio Governato, Tobias Kaufmann
Comments: 41 pages, 15 figures, Invited Review accepted for publication on Advanced Science Letters.
Obzor posvyashen modelirovaniyu (a, stalo byt', i ponimaniyu) processa obrazovaniya diskovyh galaktik. Poskol'ku problema daleka ot okonchatel'nogo resheniya, obzor soderzhit v sebe intrigu, chto delaet chtenie interesnym.
Authors: Pierre Morel, Yveline Lebreton
Comments: 13 pages, 1 figure, accepted for publication in Astrophysics & Space Science, ESTA/CoRoT Volume
Podrobno opisyvaetsya paket programm dlya rascheta zvezdnoi evolyucii. Raschety odnomernye. Ne uchityvaetsya vyrozhdenie elektronov.
Navernoe, mnogiem budet interesno takzhe prosmotret' stat'yu arxiv:0801.2022. V nei avtor rassuzhdaet o perspektivah mikrosekundnoi zvezdnoi astrometrii (na takom urovne budet rabotat' sputnik GAIA). Okazyvaetsya, eta zadacha brosaet vyzov i zvezdnym modelyam. Kogda astrometriya vyidet na mikrosekundnyi uroven', odnomernymi modelyami budet uzhe ne oboitis'.
Authors: K. Dolag, S. Borgani, S. Schindler, A. Diaferio, A.M. Bykov
Comments: 42 pages, 16 figures, accepted for publication in Space Science Reviews, special issue "Clusters of galaxies: beyond the thermal view", Editor J.S. Kaastra, Chapter 12; work done by an international team at the International Space Science Institute (ISSI), Bern, organised by J.S. Kaastra, A.M. Bykov, S. Schindler & J.A.M. Bleeker
Poyavilsya celyi ryad statei, posvyashennyh razlichnym aspektam issledovaniya
skoplenii galaktik. Pri etom bol'shinstvo statei yavlyayutsya obzorami, imeyushimi
bolee shirokuyu oblast' primenimosti, chem tol'ko skopleniya. Vmeste oni
formiruyut celuyu knigu.
Perechislyu nekotorye iz nih.
Nonthermal radiation
mechanisms,
Thermal radiation processes,
Equilibration processes in the
Warm-Hot Intergalactic Medium ,
Cosmological shock waves,
Observations of extended radio
emission in clusters,
Nonthermal phenomena in clusters
of galaxies,
Clusters of galaxies: setting the
stage ,
Clusters of galaxies: beyond the
thermal view,
Future instrumentation for the
study of the Warm-Hot Intergalactic Medium,
Metal enrichment processes,
Numerical simulations of the
Warm-Hot Intergalactic Medium.
Authors: Zachariah B. Etienne et al.
Comments: 22 pages, 14 figures, submitted to Phys.Rev.D
Avtory predstavlyayut rezul'taty chislennogo modelirovaniya sliyaniya chernoi dyry i neitronnoi zvezdy, poluchennye s pomosh'yu novogo koda. Napomnyu, chto takie sobytiya vo-pervyh, sovershenno tochno yavlyayutsya moshneishimi istochnikami gravitacionnyh voln (i, skoree vsego, LIGO pervymi uvidit imenno ih), a vo-vtoryh, kakoe-to vremya takie sobytiya obsuzhdalis' kak istochniki korotkih gamma-vspleskov.
Rezul'taty podtverzhdayut, chto gamma-vsplesk sdelat' trudno, t.k. pochti vse veshestvo neitronnoi zvezdy srazu provalivaetsya v dyru, i lish' zhalkie procenty idut na obrazovanie diska. Razumeetsya, avtory rasschityvayut formu gravimpul'sa. Sravnenie rezul'tatov raschetov s dannymi o budushih "otlovlennyh" vspleskah gravizlucheniya pozvolit dat' vazhnye ogranicheniya na uravnenie sostoyaniya neitronnyh zvezd.
Authors: W. Schmidt
Comments: 18 pages, 7 figures; proceedings contribution to "Structure formation in the Universe: Chamonix 2007"
Nebol'shoi obzor, posvyashennyi dostatochno populyarnomu izlozheniyu togo, kak modeliruyut turbulentnost' voobshe, a v osobennosti v sluchae mezhzvezdnoi sredy.
Authors: Alexander Shirokov
Comments: 90 pages
Dano pisanie novoi versii programmy dlya kosmologicheskih vychislenii (metodom mnogih tel).
Programma dostupna na stranice proekta.
Authors: J.R. Zaurin et al.
Comments: MNRAS, 12 pages
ULIRGs (UltraLuminous InfraRed Galaxies) - tak nazyvayut galaktiki so svetimostyami, prevyshayushimi v infrakrasnom diapazone LIR > 1012 svetimostei Solnca. Stol' moshnoe izluchenie voznikaet blagodarya pylevym chasticam, pereizluchayushim v infrakrasnom diapazone opticheskoe i ul'trafioletovoe izluchenie aktivnyh galakticheskih yader i oblastei intensivnogo zvezdoobrazovaniya. Samoi blizkoi k nam galaktikoi iz klassa ULIRG yavlyaetsya Arp220 (z = 0.018). Spektroskopicheskih nablyudenii ULIRGs poka nemnogo, i blizost' Arp220 predstavlyaet unikal'nuyu vozmozhnost' dlya izucheniya zvezdnogo sostava etoi galaktiki. Spektry Arp220 byli polucheny avtorami na 4.2 metrovom teleskope WHT. Dlya interpretacii spektrov byli ispol'zovany chislennye modeli populyacionnogo sinteza. Rezul'taty modelirovaniya pokazali, chto v galaktike dominiruet izluchenie zvezd s vozrastami ot 0.5 do 0.9 mlrd let, a takzhe molodyh zvezd s vozrastom menee 0.1 mlrd let. Po mneniyu avtorov, eti zvezdnye naseleniya harakterizuyut aktivnye etapy galakticheskogo sliyaniya, rezul'tat kotorogo my i nablyudaem kak galaktiku Arp220.
Authors: M. Cervino & V. Luridiana
Comments: conf.proceedings, 4 pages
Nebol'shaya zametka, poyasnyayushaya detali generacii sinteticheskih spektrov galaktik v ramkah proekta Virtual'noi Observatorii. Otdel'noe vnimanie udelyaetsya obsuzhdeniyu sistematicheskih oshibok ispol'zuemyh modelei. Nektorye osobennosti raboty Virtual'noi Observatorii obsuzhdayutsya takzhe v preprintah:
arXiv:0711.0412 3D Spectroscopy in the Virtual Observatory: Current Status;
arXiv:0711.1889 Visualization of Complex Observational and Theoretical Datasets in the Virtual Observatory;
arXiv:0711.1892 Middleware for Data Visualization in VO-enabled Data Archives;
arXiv:0711.2629 Theoretical models in the Virtual Observatory.
Authors: S. Recchi1 & G. Hensler
Comments: A&A, 13 pages
Bogatye gazom karlikovye galaktiki podrazdelyayut na karlikovye irregulyarnye nizkoi poverhnostnoi yarkosti (dIrr), i yarkie golubye karlikovye galaktiki (BCD). I te, i drugie imeyut nizkuyu metallichnost' i slozhnuyu mnogokomponentnuyu gazovuyu strukturu. Ih mezhzvezdnaya sreda sostoit iz holodnoi, teploi i goryachei diffuznoi faz. Avtory dannoi raboty issledovali, kak uchet holodnyh oblakov povliyaet na dinamicheskuyu i himicheskuyu evolyuciyu karlikovyh galaktik. Rezul'taty modelirovaniya sravnivalis' avtorami s ih zhe rezul'tatami, no poluchennymi v ramkah standartnogo obsheprinyatogo podhoda. Chislennye eksperimenty pokazali, chto uchet holodnoi oblachnoi fazy umen'shaet teplovuyu energiyu MZS na 20-40%, chto sushestvenno umen'shaet veroyatnost' obrazovaniya krupnomasshabnyh istechenii. Obshaya metallichnost' MZS karlikovoi galaktiki pri etom ponizhaetsya na 0.2-0.4 poryadka dex, hotya otnositel'nye soderzhaniya elementov ostayutsya prezhnimi.
Authors: P. Demarque, D.B. Guenther, L.H. Li, A. Mazumdar, C.W. Straka
Comments: 10 pages, 2 figures, ApSS accepted
Dano opisanie odnogo iz kodov, opisyvayushih evolyuciyu normal'nyh zvezd. Sushestvuet neskol'ko modifikacii etogo nabora programm. Nekotorye iz nih dostatochno detal'ny dlya prilozheniya k astroseismologii i issledovaniyam vnutrennego stroeniya Solnca.
Authors: Masahiro N. Machida, Kohji Tomisaka, Tomoaki Matsumoto, Shu-ichiro Inutsuka
Comments: 45 pages,12 figures, Submitted to ApJ
Avtory provodyat trehmernoe chislennoe modelirovanie evolyucii zamagnichennogo molekulyarnogo oblaka s cel'yu vyyasneniya togo, kak obrazuyutsya dvoinye zvezdy. Avtory predskazyvayut, chto u zvezd v ochen' molodyh gruppah dolzhno nablyudat'sya dva pika v raspredelenii po bol'shim poluosyam orbit dvoinyh.
Sm. takzhe arxiv:0709.2886 i arxiv:0709.2887, posvyashennye analogichnym issledovaniyam - obrazovanie zvezd. Zdes' avtory detal'no issleduyut rol' magnitnyh polei pri kollapse oblaka. Vyvody otlichayutsya ot poluchennyh v opisannoi vyshe stat'e.
Authors: Igor Chilingarian
Comments: 2 pages, 1 figure, Stellar Populations as Building Blocks of Galaxies, Proceedings of IAU Symposium #241. Edited by A. Vazdekis and R. F. Peletier. Cambridge: Cambridge University Press, 2007, pp.177-178
Sravnivayutsya dva podhoda pri organizacii dostupa k dannym o zvezdnyh populyaciyah v Virtual'noi observatorii. K sozhaleniyu, zametka ochen' korotkaya, poetomu, po suti, prihoditsya dovol'stvovat'sya lish' vyvodami avtora. Vse detali ostayutsya za bortom.
Authors: Daniel J. Price
Comments: 14 pages, 11 figures, accepted to PASA
Avtor opisyvaet (i reklamiruet) soft dlya vizualizacii gidrodinamicheskih raschetov metodom sglazhennyh chastic. Programma dostupna dlya skachivaniya.
Authors: Paul Arthur Navratil, Jarrett L. Johnson, Volker Bromm
Comments: 7 pages, to appear in IEEE Transactions on Visualization and Computer Graphics (Proceedings of IEEE Visualization 2007), Nov/Dec 2007.
Dovol'no interesno, kak lyudi pytayutsya optimizirovat' vizualizaciyu rezul'tatov raschetov formirovaniya pervyh zvezd i tp.
Authors: Hsi-Yu Schive, Chia-Hung Chien, Shing-Kwong Wong, Yu-Chih Tsai, Tzihong Chiueh
Comments: 30 pages, 20 figures, submitted to NewAstronomy, 20 July, 2007
Bukval'no neskol'ko dnei nazad izvestnyi rossiiskii nauchnyi zhurnalist Aleksandr Sergeev, zaidya v GAISh rasskazyval mne v 31-i komnate za chashkoi chaya o vozmozhnosti sozdaniya klasterov s proizvoditel'nost'yu neskol'ko teraflop na videokartah NVIDIA. Ya kak-to skepticheski otnessya k etomu (proizvoditel'nost'-to bol'shaya, no vot kak tam s pamyat'yu.... Vse ravno eto ne deshevo po nashim merkam, vozni mnogo i tp.). No vot - kitaicy uzhe blagopoluchno gonyayut takie sistemy na astrofizicheskih zadachah.
Hotya, vse ravno, samaya krasivaya ideya - eto klastery na XBOX pod Linux. Delo v tom, chto igrovye pristavki v principe mozhno kupit' deshevle sebestoimosti, esli proizvoditel' vedet nekotoruyu rynochnuyu igru i dumaet v pervuyu ochered' ob osnovnyh potrebitelyah, kotorye pokupayut po odnoi pristavke, a potom kuchu igr :)
Obsudit' v ZhZh-soobshestve
ru_astroph.
Obsudit' na Astroforume v
Nauchnoi panorame.
Authors: Piet Hut, Shin Mineshige, Douglas C. Heggie, Junichiro Makino
Comments: 23 pages, to appear in Prog. Theor. Phys
Rassmotreny razlichnye aspekty modelirovaniya tesnyh zvezdnyh sistem, v kotoryh vozmozhny chastye vzaimodeistviya zvezd (zahvaty, obmeny i tp.).
Authors: Katrin Heitmann et al.
Comments: 28 pages, 14 figures
Seichas v mire sushestvuet dostatochno mnogo grupp, zanimayushihsya chislennym modelirovaniem formirovaniya krupnomasshtabnoi struktury. Dlya vnyatnogo obsuzhdeniya rezul'tatov, poluchennyh etimi gruppami, neobhodimo sravnivat' sami komp'yuternye programmy. Dlya etogo nado provodit' nekotorye standartnye vychisleniya, i detal'no razbirat'sya net li protivorechii v raznyh kodah. Etim uzhe neskol'ko let zanimayutsya. V stat'e predstavleny ocherednye rezul'taty sravneniya. Vrode by vse horosho.
Authors: Michael L. Norman et al.
Comments: 22 pages, 6 figures. To appear in Petascale Computing: Algorithms and Applications, Ed. D. Bader, CRC Press LLC (2007)
Podrobno, no ochen' ponyatno (bez massy formul i tp.) opisana komp'yuternaya programma i ee primeneniya dlya kosmologicheskih vychislenii. Rekomenduyu vsem, kto interesuetsya tem, kak provodyatsya moshnye vychisleniya v sovremennoi astrofizike.
Authors: S. Rosswog, D. Price
Comments: 18 pages, 17 Figures
Predstavleno opisanie novoi programmy, prednaznachennoi dlya rascheta sliyanii neitronnyh zvezd (a takzhe neitronnyh zvezd s chernymi dyrami).
Authors: V.M. Lipunov, K.A. Postnov, M.E. Prokhorov, A.I. Bogomazov
Comments: 32 pages, 3 figures
Dano podrobnoe opisanie formul, zalozhennyh v programmu populyacionnogo sinteza dvoinyh sistem "Mashina scenariev".
Authors: A. G. Hoekstra, et al.
Comments: 20 pages, To appear in D. Bader (Ed.) Petascale, Computing: Algorithms and Applications, Chapman & Hall / CRC Press, Taylor and Francis Group
"Vpered, k pobede kommunizma!" (s)
Chto-to v etom duhe prihodit v golovu v svyazi s nazvaniem stat'i.
Avtory obsuzhdayut raspredelennye vychisleniya
(grid computing) s
proizvoditel'nost'yu poryadka
petaflop v sekundu.
Grid computing trebuet razrabotki special'nyh algoritmov. Avtory kratko ih obsuzhdayut i razvernuto illyustriruyut.
Etot podhod aktualen dlya samyh raznyh oblastei. Stat'ya poyavilas' imenno v astronomicheskoi chasti Arhiva, poskol'ku chast' avtorov yavlyaetsya astrofizikami, i primer dlya illyustracii oni vybrali astronomicheskii - modelirovanie galaktiki.
Authors: P. Cerd-Durn, J. A. Font, H. Dimmelmeier
Comments: 25 pages, 14 figures, submitted to Astronomy & Astrophysics on March 7, 2007
Predstavleny rezul'taty raschetov sverhnovoi dlya magnito-rotacionnogo mehanizma. Kak ya uzhe ne raz podcherkival, nakonec-to etot mehanizm stal aktivno issledovat'sya raznymi gruppami. Vse eto yasnyi primer togo, kak razvitie vychislitel'noi tehniki (imeetsya vvidu ne tol'ko "zhelezo", no i "soft") privodit k detalizacii modelei i rassmotreniyu bolee shirokogo spektra mehanizmov.
Authors: Eric Gourgoulhon
Comments: Lectures given at the General Relativity Trimester held in the Institut Henri Poincare (Paris, Sept.-Dec. 2006) and at the VII Mexican School on Gravitation and Mathematical Physics (Playa del Carmen, Mexico, 26. Nov. - 2 Dec. 2006), 220 pages, 25 figures.
Fakticheski, eto kniga, posvyashennaya ochen' populyarnoi seichas tematike - chislennomu modelirovaniyu effektov OTO. Nikakogo "obshego" interesa rabota ne predstavlyaet, no, po vsei vidimosti, yavlyaetsya polezneishim rukovodstvom dlya teh, kto v samom dele etim zanimaetsya.
Authors: A. Ciardi et al.
Comments: 34 Pages, 10 Figure, Submitted to Physics of Plasmas
Zamechatel'nyi sintez laboratornyh eksperimentov i chislennogo modelirovaniya, sozdannyi dlya luchshego ponimaniya feericheskih astrofizicheskih fenomenov - struinyh istechenii, nablyudaemyh, v osnovnom, ot akkreciruyushih chernyh dyr.
Authors: Masaru Shibata, Koji Uryu
Comments: 14 pages. To appear in a special issue of Classical and Quantum Gravity: New Frontiers in Numerical Relativity
Predstavleny rezul'taty novyh chislennyh raschetov sliyanii sistem, sostoyashih iz neitronnyh zvezd i chernyh dyr. Vazhno, chto avtory nahodyat novye argumenty v pol'zu togo, chto takie sistemy mogut porozhdat' korotkie gamma-vspleski.
Authors: Oscar Agertz et al.
Comments: 15 pages, 13 figures, to be submitted to MNRAS. For high-resolution figures, please see this http URL
Sushestvuyut razlichnye metody chislennogo modelirovaniya v kosmologii. Avtory stat'i sravnivayut dva podhoda: SHP (smoothed particle hydrodynamics) i setochnye metody. Rassmatrivayutsya model'nye zadachi s izvestnymi resheniyami. Proizveditsya chislennyi schet s pomosh'yu razlichnyh metodik.
Rezul'taty nedvusmyslenno govoryat o tom, chto setochnye metody kuda kak luchshe opisyvayut real'nost'. Svyazano eto s tem, chto oni luchshe mogut opisyvat' razvitie neistoichivostei (naprimer, Relei-Teilorovskoi). V kosmologii eto vazhno, naprimer, dlya raschetov dvizheniya galaktik v skopleniyah.
Authors: Piet Hut
Comments: 16 pages
Po-moemu, ochen' interesnaya stat'ya o sovremennom podhode k chislennomu modelirovaniyu voobshe i v astrofizike, v chastnosti. Ya sam v etom otnoshenii chelovek ochen' dremuchii. Poetomu bylo osobenno interesno pochitat' "kak vse moglo by byt'".
Authors: Igor V. Igumenshchev
Comments: 31 pages, 7 figures attached in jpg-format; to appear in ApJ
Teoriya akkrecii razvivaetsya uzhe dostatochno davno. Tem ne menee, dazhe dlya dostatochno prostyh techenii ne dostignuto polnoe ponimanie. Kak yasno iz nazvaniya stat'i, v nei providitsya chislennoe issledovanie trehmernoi sfericheski-simmetrichnoi akkrecii s uchetom magnitnyh polei.
Kak i v bolee rannih issledovaniyah (v tom chisle i samogo avtora stat'i) temp akkrecii konechno zhe men'she, chem v sluchae klassicheskoi akkrecii Bondi. Vazhnym novym vyvodom yavlyaetsya nevozmozhnost' ustanovleniya stacionarnogo sverhzvukovogo sfericheski-simmetrichnogo techeniya pri nalichii melkomasshtabnyh magnitnyh polei.
Authors: Matthew D. Duez et al.
Comments: 27 pages, 30 figures; Journal-ref: Phys. Rev. D73 (2006) 104015
Privodyatsya rezul'taty chislennogo modelirovaniya povedeniya molodyh neitronnyh zvezd s uchetom mnogih detalei.
Authors: K. Belczynski et al.
Comments: 34 pages, 13 figures, submitted to ApJS
Privoditsya podrobnoe opisanie odnoi iz luchshih sovremennyh programm populyacionnogo sinteza tesnyh dvoinyh sistem - StarTrack. Sootvetstvenno, iz opisaniya togo kak i chto schitaetsya, mozhno uznat' mnogo poleznogo ob evolyucii zvezd v dvoinyh sistemah, osobenno o sistemah s kompaktnymi ob'ektami.
Authors: Masaru Shibata et al.
Comments: 4 pages, 2 figures, submitted to Phys. Rev. Letter
V proshlom vypuske ya uzhe pisal o pervoi rabote etoi gruppy avtorov. Imi rassmatrivaetsya kollaps bystrovrashayusheisya massivnoi zamagnichennoi neitronno zvezdy, obrazovavsheisya v reuzl'tate sliyaniya dvuh neitronnyh zvezd. V predydushei stat'e avtorami lish' kratko byla otmechena vozmozhnost' generacii korotkogo gamma-vspleska pri takom kollapse. V etoi zhe stat'e modelirovanie vspelska yavlyaetsya osnovnoi temoi.
Authors: G.S.Bisnovatyi-Kogan, S.G.Moiseenko, N.V.Ardeljan
Comments: 23 pages, 48 figures, Proc. of the workshop "Gravity, Astrophysics and Strings at the Black Sea" June 13-20, 2005, Bulgaria
Ocherednaya stat'ya izvestnoi rossiiskoi gruppy, razrabatyvayushei model' magnitorotacionnogo vzryva sverhnovoi. Poskol'ku model' postoyanno razvivaetsya, sovershenstvuetsya, to novye stat'i soderzhat novye detali. Rekomenduetsya k prochteniyu vsem, kogo interesuet, kak vzryvayutsya massivnye zvezdy (rech' idet tol'ko o takih sverhnovyh, t.e. ne o tipe Ia).
Authors: M. Cervino, V. Luridiana
Comments: 35 pages, 16 figures. Invited review to "Resolved Stellar Populations", Cancun (Mexico) Apr 2005. To appear on the proceedings of the conference edited by D. Valls-Gabaud & M. Chavez, ASP Conf. Ser. (ASP: San Francisco)
oNDPNAMN NAYaSFDYuERYa' NDHM HG BYuFMShU YuYaOE'RNB ONOSK'ZhHNMMShU LNDEKEI B YuYaRPNTHGH'E.
Authors: Stuart L. Shapiro
Comments: to appear in `The Next Chapter in Einstein's Legacy'', Proceedings of YKIS 2005, Kyoto, Japan, eds M. Sasaki, J. Soda and T. Tanaka, in Progress of Theoretical Physics Suppl, in press (2006)
Takoi vot dlinnyi perevod nazvaniya. Sut' raboty konechno v tom, chto zhe novogo est' v chislennom modelirovanii processov, v kotoryh veliki effekty Obshei teorii otnositel'nosti. Zadachi eti vo-pervyh seichas ochen' aktual'ny (naprimer, v svyazi s perspektivoi registracii gravitacionnyh signalov ot slivayushihsya chernyh dyr), vo-vtoryh oin stanovyatsya bolee dostupnymi v smysle togo, chto moshnost' komp'yuterov vse eshe rastet. No odnoi mosh'yu tut krepost' ne vzyat'. Nuzhno razrabatyvat' novye algoritmy. Etomu sobstvenno i posvyashen obzor.
Authors: Volker Springel
Comments: submitted to MNRAS, 31 pages, 20 figures (reduced resolution), code available at http://www.mpa-garching.mpg.de/gadget
Predstavleno detal'noe opisanie odnogo iz kosmologicheskih kodov. Sam kod dostupen.
Authors: M. Cervino, V. Luridiana, N. Cervino-Luridiana
Comments: 20 pages, 8 figures, submitted to A&A.
Migel' Chervin'o sdelal uzhe neskol'ko ochen' interesnyh rabot, posvyashennyh predelam primenimosti evolyucionnogo populyacionnogo sinteza. Kak vidno iz nazvaniya, eto chetvertaya rabota v serii. Rabota dostatochno tehnicheskaya, no na moi vzglyad vazhnaya.
Authors: Douglas C. Heggie
Comments: 29 pages, 4 figures, to appear in Encyclopaedia of Mathematical Physics, Elsevier, 2006
Obshirnaya enciklopedicheskaya stat'ya, posvyashennaya metodu mnogih tel v gravitacii.
Vse znayut, chto uzhe zadacha treh tel v obshem vide ne imeet polnogo analiticheskogo resheniya. Odnako v astronomii splosh' i ryadom vstrechayutsya situacii vzaimodeistviya mnozhestva ob'ektov. Dlya resheniya takih zadach byli razrabotany kak chislennye, tak i priblizhennye analiticheskie metody. Obo vsem etom - v stat'e.
Authors: Marina M. Romanova et al.
Comments: 5 pages with 4 figures, LaTeX, macros: emulapj.sty, avi movies are available at http://www.astro.cornell.edu/us-russia/disk_prop.htm; Journal-ref: ApJ Letters, 616, L151-L154, 2004
Chestno govorya, vsegda nravilis' kartinki i fil'my, demonstriruyushie diskovuyu
akkreciyu.
Rassmotren rezhim propellera pri diskovoi akkrecii na zamagnichennuyu zvezdu.
Rezul'taty mogut primenyat'sya kak dlya akkrecii na neitronnye zvezdy i belye
karliki, tak i dlya issledovaniya zvezd tipa T Tel'ca.
Na pervoi serii risunkov pokazano, kak izmenyaetsya konfiguraciya magnitnogo polya. Na levom risunke (T=0, vremya otschityvaetsya v uslovnyh edinicah, sootvetstvuyushih odnomu oborotu s keplerovskoi skorost'yu na rasstoyanii 2.86 radiusa zvezdy) pokazana nachal'naya konfiguraciya polya. Zatem nachinaetsya raschet, i vidno, kak silovye linii formiruyut "magnitnye bashni". V nizhnei chasti dano uvelichennoe izobrazhenie linii vblizi diska dlya T=70.
Na vtoroi serii risunkov prodemonstrirovano, chto nesmotrya na to, chto sistema nahoditsya na stadii propellera, kogda bystrovrashayusheesya magnitnoe pole prepyatstvuet proniknoveniya veshestva na poverhnost' zvezdy, nekotoraya akkreciya tem ne menee vozmozhna. Na srednem risunke otchetlivo vidno eto "proniknovenie".
Authors: James M. Stone, Thomas A. Gardiner
Comments: 11 pages, style files included, Conference Proceedings: "Magnetic Fields in the Universe: from Laboratory and Stars to Primordial Structures", More information on Athena can be found at http://www.astro.princeton.edu/~jstone/athena.html
Authors: Thomas A. Gardiner, James M. Stone
Comments: 45 pages, 13 figures, accepted for publication in J. Comp. Phys.
Dve stat'i, v kotoryh opisyvaetsya chislennaya shema i kod dlya modelirovaniya magnito-gidrodinamicheskih processov. Krome opisaniya predstavleny rezul'taty testov programmy. Veroyatno, etot kod pridet na smenu znamenitomu ZEUS.
Authors: Charles F. F. Karney
Comments: 52 pages, 13 figures. Presented at 3rd European Workshop on Problems in the Numerical Modeling of Plasmas, Varenna, Italy, September 10-13 (1985). Reprinted in "Problems in the Numerical Modeling of Plasmas", edited by K. Appert (1986)
Staraya, no aktual'naya stat'ya, posvyashennaya vzaimodeistviyu radiovoln s plazmoi.
Authors: Alexander Knebe
Comments: 8 pages, 4 figures, accepted for publication in PASA (refereed proceedings contribution for the meeting "Gravity 2004" held in Sydney, April 15-16, 2004)
Kratko opisany osnovnye metody kosmologicheskogo modelirovaniya metodom mnogih tel (N-body). Poskol'ku dannye po krupnomasshtabnoi strukture yavlyayutsya odnim iz kitov, na kotoryh stoit sovremennaya kosmologiya, sovetuem oznakomit'sya s etim obzorom.
Authors: J.S. Bagla
Comments: Invited Review; To appear in Current Science (special issue on Cosmology, Guest editor T.Padmanabhan)
Naravne s dannymi po reliktovomu izlucheniyu i pervichnomu nukleosintezu issledovaniya krupnomasshtabnoi struktury yavlyayutsya odnim iz stolpov, na kotoryh stoit zdanie sovremennoi kosmologii. S teoreticheskoi tochki zreniya rassmotrenie modelei obrazovaniya galaktik i ih skoplenii i sverhskoplenii svoditsya v osnovnom kak raz k metodu mnogih chastic (N-Body simulations). V stat'e provoditsya obstoyatel'nyi obzor dannogo metoda komp'yuternogo modelirovaniya.
Otmetim, chto poyavilos' eshe neskol'ko obzorov, kotorye budut napechatany
v special'nom vypuske
Current Science.
Authors: Daisuke Nagai, Andrey V. Kravtsov
Comments: 3 pages, 2 figures. Use iaus style. To appear in the proceedings of IAU Colloquium 195 - "Outskirts of galaxy clusters: intense life in the suburbs", Torino, Italy, March 12-16, 2004
Ochen' korotkaya zametka v trudah konferencii. My vydelyaem ee potomu, chto uzhe v abstrakte kompaktno i chetko perechisleny osnovnye elementy i trudnosti v modelirovanii processa formirovaniya galaktik i skoplenii, a takzhe vozmozhnye puti razresheniya etih problem.
Trudnosti svyazany s pravil'nym uchetom ohlazhdeniya gaza za schet izlucheniya i nagreva gaza za schet obratnogo vliyaniya obrazuyushihsya zvezd. Dlya vosproizvedeniya nablyudayushihsya svoistv galaktik neobhodim kakoi-to dopolnitel'nyi mehanizm nagreva. Vozmozhno, on svyazan s aktivnost'yu galakticheskogo yadra.
Authors: Theodore Liolios
Comments: 9 RevTex pages, 8 figures.
Eta stat'ya opisyvaet dve programmy na FORTRAN'e, kotorye pozvolyayut stroit' diagrammy Gercshprunga-Rassela i evolyucionnye treki otdel'nyh zvezd na nei. Programma pozvolyaet zadavat' takie parametry "risuemoi" zvezdy, kak himsostav (central'nyi i fotosfernyi), svetimost', effektivnuyu temperaturu, radius fotosfery i massu zvezdy. Sami programmy dostatochno prosty, no snabzheny ochen' bol'shim naborom failov s dannymi. A za grafiku otvechaet horosho izvestnyi svobodno rasprostranyaemy paket programm PGPLOT.
Authors: Michael L. Norman
Comments: 21 pages, 0 figures.
AMR (Adaptive Mesh Refinement) oznachaet "metod adaptivnyh setok" odin iz samyh prodvinutyh metodov chislennogo gidrodinamicheskogo i magnitogidrodinamicheskogo modelirovaniya, kogda trebuetsya smodelirovat' processy v dostatochno bol'shom ob'eme prostranstva i pri etom prosledit' za melkimi detalyami, voznikayushimi v nekotoryh ego mestah.
A primenyayutsya eti metody dlya modelirovaniya Solnca, mezhzvezdnoi sredy, vspyshek Sverhnovyh, processov nukleosinteza, zvezdoobrazovaniya, dzhetov, obrazovaniya i evolyucii galaktik i krupnomasshtabnoi struktury Vselennoi. I tak dalee ...
(Pri etom ni odnogo risunka.)
Authors: M.M.Romanova et al.
Comments: 26 pages, 22 figures, ApJ, 595 (2003), 1009-1031
Eto ne pervaya rabota dannyh avtorov po chislennoi MGD, do etogo byla akkreciya na soosnyi dipol', na bystro dvizhushuyusya, no nevrashayushuyusya zvezdu i t.d.
Stat'yu mozhno chitat' dvumya sposobami: vnimatel'no vchityvat'sya v ispol'zovannye granichnye usloviya i parametry sredy - eto dlya specialistov gidrodinamikov, fizikov plazmy i astrofizikov, ili prosto smotret' na kartinki - ih mnogo i nizhe privedena odna iz samyh prostyh i ne krasochnyh.
Na saite avtorov mozhno posmotret' fil'm, sledannyi po etim raschetam: http://www.astro.cornell.edu/us-rus/inclined.htm.
Authors: H.-Th. Janka et al. Astrophysics, Garching)
Comments: 8 pages, 3 figures, high-quality available upon request; contribution to Procs. IAU Coll. 192, "Supernovae", Eds. J.M. Marcaide ad K.W. Weiler, Springer
Ochen' malen'kii obzor odnoi iz samyh avtoritetnyh grupp po chislennomu modelirovaniyu Sverhnovyh. Chto stalo yasno na segodnyashnii den': dvumernye osesimmetrichnye modeli, dazhe s ochen' izoshrennym perenosom neitrino, ne priveli k uspehu. No est' yavnye priznaki togo, chto (v trehmerii) dannaya problema blizka k resheniyu.
(Arhiv Chislennoe modelirovanie: v.2, 2003,
v.1, 2002-2003)
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