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تسجيل مستخدم جديدExtinction Corrected Star Formation Rates Empirically Derived from Ultraviolet-Optical Colors
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Using a sample of galaxies from the Sloan Digital Sky Survey spectroscopic catalog with measured star-formation rates (SFRs) and ultraviolet (UV) photometry from the GALEX Medium Imaging Survey, we derived empirical linear correlations between the SFR to UV luminosity ratio and the UV-optical colors of blue sequence galaxies. The relations provide a simple prescription to correct UV data for dust attenuation that best reconciles the SFRs derived from UV and emission line data. The method breaks down for the red sequence population as well as for very blue galaxies such as the local ``supercompact UV luminous galaxies and the majority of high redshift Lyman Break Galaxies which form a low attenuation sequence of their own.
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