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تسجيل مستخدم جديدMatching the Local and Cosmic Star Formation Histories
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Igor Drozdovsky
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Given the many recent advances in our understanding of the star formation history (SFH) of the Local Group and other nearby galaxies, and in the evolution of star formation with redshift, we present a new comparison of the comoving space density of the star formation rate as a function of look-back time for the Local and Distant Universe. We update the Local SFH derived from the analysis of resolved stellar populations (``fossil records) in individual nearby galaxies, based on our own estimations as well as available in the literature. While the preliminary comparison of SFHs is found to be broadly consistent, some discrepancies still remain, including an excess of the Local SFR density in the most recent epoch.
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In this review I will describe a number of recent advances in extragalactic astronomy. First of all I will describe our current best estimates of the star formation history of the Universe. Then I will describe measurements of local galaxies and thei
r stellar populations, concentrating on measurements of the luminosity functions and stellar population compositions of the different kinds of galaxies. Finally, I will investigate the relationship between these two sets of results. The ultimate aim is to tell at what stage in the history of the Universe the different stars seen in the local galaxies formed. At present much is known but there are significant uncertainties and I will highlight some prospects for the future.
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