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test mail - pls ignore - this should *fail*
by Boud Roukema 15 Nov '02

15 Nov '02

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czesc
by Ewa Pilichowski 15 Nov '02

15 Nov '02

Tak to prawda zosta³e¶/a¶ wybrany/a! Ten mail oznacza ¿e prawdopodobnie staniesz siê cz³onkiem najwspanialszej grupy internautów w polsce... A to dlatego ¿e Ewa22 zaprasza Ciê na stronê epuls.pl! ;) Wiadomo¶æ od Ewa22: Witam! Zapraszam na nowa polska strone www.epuls.pl! Swietne miejsce na spotykanie ciekawych ludzi, nawiazanie nowych relacji i kontaktow, albo po prostu pogadac ze starymi znajomymi! www.epuls.pl - siec tetni naszym pulsem moj adres: http://ewa22.epuls.pl Kliknij tutaj: http://www.epuls.pl/recruitments.php?rid=2eb3dccb

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wyklade kosmologia - lista mejla + wikipedia
by Boud Roukema 29 Aug '02

29 Aug '02

<cross-post cosmo-pl,cosmo-intro> ** STRESZCZENIE - dla wyk�ad�w kosmologia obserwacyjnej [pl], istnieje dw�ch cyber-miesjce: lista mejla - http://www.astro.uni.torun/sympa/cosmo-intro/ szkic stron encyklopedia - http://pl.wikipedia.com/wiki.cgi?Kosmologia_obserwacyjna ** Cze�� wszystkim, P�niej urlop, do pracy... :) Wsp�cze�stwo kosmologii w po polsku jeszcze jest ma�e, my�l� �e uczy� kosmologia obserwacyjna do studenci jest bardzo wa�ny. Trwa� nowy semestr, b�d� najmniejszy dwa kurs wyk�adowy o kosmologii: * Bronek Rudak - w UMK - Toru� * Staszek Bajtlik - w UW - Warszawa Czy te� b�dzie wyk�ady kosmologii w Krakowie? Lub w po polsku w inne miejsce? Moim skromnym zdaniem, cel wyk�ade potrzeba by� (1) �e studenci uczy� si� kilka najwa�niejsze zdanie i dane kosmologia obserwacyjne (2) �e studenci uczy� si� *jak* uczy� si� z technologi� moderna internetowy: - szuka� informacji kosmologi� w sajcie jak http://www.google.com/ - koordynowa� uczenie si� *dla siebie* z - tworzy� pliki tekstowy z emacs-em, systeme GNU/Linux http://www.gnu.org - z listami mejla kosmologi� http://www.astro.uni.torun.pl/sympa/ - robi� syntezis i analyz informacja kosmologiego My�l� �e Bronek i Staszek zgadzaj� si�... ? (3) Wi�c, (3a) Andrzej Marecki i ja tworzyli�my lista mejla z archiwami otwarte (http://www.sympa.org) dla ca�a dyskusja o ten temat, np data, czas i miejsce wyk�ade, komunikacja wolna mi�dzy studenci warszawskiego i toru�skiego, URLy do "dobre" sajte jak ju� istnieje o tre�� wyk�ade, itd. Jest tu: http://www.astro.uni.torun/sympa/cosmo-intro/ Prosz� praszajcie studenci wyk�ade cosmologii (i wyk�ad�wce!) do subscribe-owa� (mailto:sympa@astro.uni.torun.pl?subject="subscribe%20cosmo-intro%20FirstName%20FamilyName")! (3b) Z inspiracj� z wyk�adem Broneka, ju� istnieje stron encyclopedia wolna (z GFDLem, jak GPL dla dokumente) o kosmologii obserwacyjnej. Witamy wszystkim, studenci lub wyk�adowce, dla poprawi� lub dla pisa� kilka akapicie lub kilka linie w wikipedia: http://pl.wikipedia.com/wiki.cgi?Kosmologia_obserwacyjna Cel jest �e te strone s� skuteczne dla rozumie� i uczy� si� - wszystko jak ma zdanie dla poprawi�, mo�e robi�! Zawsze b�d� stare wersje, wi�c mo�e zmieni� z wolno�ci... Pozdrawiam boud

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data base of clusters of galaxies
by Boud Roukema 29 Mar '02

29 Mar '02

A data base for clusters of galaxies has been created in Toulouse. This will be complementary to existing databases such as NED http://ned.ipac.caltech.edu and the CDS http://cdsweb.u-strasbg.fr It should contain bibliographic data and published observed properties of clusters, it started in October 2001 (according to the announcement, in French, it started in "October 2002" ;) ) and apparently contains a little more than 1500 clusters of which 1470 have flux measurements and 205 have estimated temperatures. The cluster database is here: http://webast.ast.obs-mip.fr/bax (BAX = Base de donn�es des Amas en rayons X, I guess) Boud

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Another confirmation of the existence of dark energy.
by Andrzej Marecki 27 Mar '02

27 Mar '02

----- Forwarded message from NewsAlert ----- NEWSALERT: Friday, March 22, 2002 @ 1504 GMT --------------------------------------------------------------------- The latest news from Astronomy Now and Spaceflight Now [...] NEW EVIDENCE: EXPANSION OF UNIVERSE IS ACCELERATING --------------------------------------------------- A team of UK and Australian astronomers has discovered new, independent evidence that the expansion of the universe is accelerating. Their findings have just appeared in the Monthly Notices of the Royal Astronomical Society. A team of 27 astronomers led by Professor George Efstathiou of the University of Cambridge has published strong evidence for the existence of dark energy using an entirely different technique. Their results show that the universe is full of dark energy, completely consistent with the earlier supernovae results. "Dark energy appears to exist and to dominate over more conventional types of matter" says Professor Efstathiou. "An explanation of the dark energy may involve String Theory, extra dimensions or even what happened before the Big Bang. At present nobody knows. The ball is now firmly in the theorists court." http://spaceflightnow.com/news/n0203/22expansion/ [...] ----- End of forwarded message from NewsAlert ----- -- Andrzej Marecki

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Re: rozmawianie w CAMKu-Warszawy dzisiaj
by bp＠astro.princeton.edu 14 Mar '02

14 Mar '02

There are two independent observing projects going on in Warsaw which have cosmological implications. Janusz Kaluzny of CAMK discovered (with his associates) a number of detached eclipsing binaries in several globular clusters. These are ideal objects to measure the ages, far superior to the traditional "isochrone fitting" method, which suffers from uncontrollable errors due to lack of understanding of convective envelopes (mixing length "theory". The method used by Kaluzny is based on the very robust mass-luminosity relation for stars near the main sequence turn-off point. Enclosed is the abstract of a relevant paper: astro-ph/0111089. This is the most reliable (so far) determination of the age of any globular cluster. More work will be done soon by Janusz Kaluzny and his collaborators. Another project is OGLE, and enclosed are two papers by its leader, Andrzej Udalski of the Warsaw University Observatory. The project provides the best (so far) determination of the distance to the Large Magellanic Cloud, which is the first step towards the determination of Hubble constant by the HST Key Project and other groups. OGLE will keep refining the LMC distance determination using variety of methods - stay tuned. Bohdan Paczynski ------------------------------------------------------ Astrophysics, abstract astro-ph/0111089 From: Janusz Kaluzny <jka(a)camk.edu.pl> Date: Mon, 5 Nov 2001 15:46:09 GMT (123kb) Photometry and Spectroscopy of Eclipsing Binaries in omega Centauri Authors: J. Kaluzny, I. Thompson, W. Krzeminski, A .Olech, W. Pych, B. Mochejska Comments: 5 pages, 3 figures, newpasp.sty, to appear in the "Omega Centauri: a Unique Window into Astrophysics" (Cambridge, Aug. 2001), ASP Conf. Ser. edited by F. van Leeuwen, G. Piotto,and J. Hughes Detached eclipsing double line spectroscopic binaries are accurate distance indicators. They can be used for the direct determination of distances to globular clusters in which such systems can be identified. The results of major photometric surveys aimed at identification of variable stars in omega Cen are summarized. Over 43 eclipsing binaries have been identified so far in the cluster field of which only 8 objects are true detached systems. Distance and age determinations are presented for the system OGLEGC-17. The apparent distance modulus is (m-M)_{V}=14.09\pm 0.04 and the age of this binary is tau=11.8\pm 0.6 Gyr. ------------------------------------------------------ Astrophysics, abstract astro-ph/9910167 From: Andrzej Udalski <udalski(a)astrouw.edu.pl> Date (v1): Fri, 8 Oct 1999 16:33:32 GMT (33kb) Date (revised v2): Sun, 10 Oct 1999 11:58:20 GMT (33kb) Date (revised v3): Fri, 14 Jan 2000 15:35:00 GMT (36kb) The Optical Gravitational Lensing Experiment. Red Clump Stars as a Distance Indicator Authors: A. Udalski Comments: 11 pages. Latex+psfig. Accepted for publictation in ApJ Letters. Major revision: 30% larger sample of Hipparcos red giants with spectroscopic metallicities and extended photometry of the LMC field red clump stars (9 lines-of-sight). Due to journal space limitation, sections on comparison of the LMC red clump distance modulus with previous determinations and relations between the color indices and metallicity removed from this version We present relation of the mean I-band brightness of red clump stars on metallicity. Red clump stars were proposed to be a very attractive standard candle for distance determination. The calibration is based on 284 nearby red giant stars whose high quality spectra allowed to determine accurate individual metal abundances. High quality parallaxes (\sigma_\pi / \pi < 10%) and photometry of these very bright stars come from Hipparcos measurements. Metallicity of the sample covers a large range: -0.6<[Fe/H]<+0.2 dex. We find a weak dependence of the mean I-band brightness on metallicity (about 0.13 mag/dex). What is more important, the range of metallicity of the Hipparcos sample partially overlaps with metallicity of field giants in the LMC, thus making it possible to determine the distance to the LMC by almost direct comparison of brightness of the local Hipparcos red clump giants with that of LMC stars. Photometry of field red clump giants in nine low extinction fields of the LMC halo collected during the OGLE-II microlensing survey compared with the Hipparcos red clump stars data yields the distance modulus to the LMC: (m-M)_LMC=18.24+/-0.08 mag. ------------------------------------------------------ Astrophysics, abstract astro-ph/0010151 From: Andrzej Udalski <udalski(a)astrouw.edu.pl> Date: Sat, 7 Oct 2000 09:34:13 GMT (161kb) The Optical Gravitational Lensing Experiment. Stellar Distance Indicators in the Magellanic Clouds and Constraints on the Magellanic Cloud Distance Scale Authors: A. Udalski Comments: 26 pages, 8 figures (3 in 'jpg'format), LaTex Journal-ref: Acta Astronomica, 50, 279 BVI photometry of the Magellanic Clouds collected during the OGLE-II microlensing experiment makes it possible to study in detail photometric properties of the "major" stellar distance indicators in the Magellanic Clouds. In addition to Cepheids, RR Lyr and red clump stars, which photometry was presented in the earlier OGLE papers, we present the so far most accurate determination of brightness of the tip of the red giant branch in the LMC and SMC. We analyze the ratios of brightness of all four distance indicators in the LMC and SMC. Additionally, we include in our analysis, when possible, photometric data of the distance indicators in the metal poor Carina dwarf galaxy for which photometry was also collected during the OGLE-II experiment. The analysis is largely differential, free from zero point and extinction uncertainties. The main conclusion is that the distance scales resulting from all four stellar distance indicators are fully consistent with each other. Therefore the distance scale problem is not a problem resulting from different distances yielded by distance indicators, but rather a problem of the proper zero point of this common distance scale. All four stellar distance indicators have to be treated as an ensemble, and any determination of the zero point for one of them must predict reasonable luminosities of the others. This puts strong constraints on many proposed calibrations of distance indicators. For example, very bright calibrations of Cepheids or RR Lyr can practically be ruled out. (Abridged). ------------------------------------------------------

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Re: rozmawianie w CAMKu-Warszawy dzisiaj
by bp＠astro.princeton.edu 11 Mar '02

11 Mar '02

I got it! Thanks a lot, Bohdan

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rozmawianie w CAMKu-Warszawy dzisiaj
by Boud Roukema 11 Mar '02

11 Mar '02

Cze�� wszysce, Dzisiaj robili�my rozmawianie informalne mi�dzy kilka ludzie kosmologyczne lub sympatyczne w CAMKu-Warsawie. Pami�tajcie �e ta lista mejla ma archiv publiczne, i lista jest dla ca�a dyskusja o badaniu kosmologia w Polsce (i oczywi�cie, morzecie zaprasa� inne kosmology dla subscribe o lista): http://www.astro.uni.torun.pl/sympa/cosmo-pl/ Bohdan m�wi� o kilka astronomy w Warszawie jak� robi� badanie bardzo interesuj�ce dla nasz, i kilka zdania o komunikacja mi�dzy astronome w samo miasto... Bohdan: prosz� pisa� jak mowi�isz o lista! (mailto:cosmo-pl@astro.uni.torun.pl) Pozdrawiam Boud PS: Przepraszam dla odmian przypadk�w jak� niedobre... ;)

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