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The nearby universe observed in far-infrared and in ultraviolet: an analysis of the dust attenuation and the star formation activity

V. Buat
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Abstract

We discuss the dust attenuation and the star formation rates in the nearby universe obtained from a comparison of far-infrared (IRAS) and ultraviolet (GALEX) observations. The ratio of the dust to UV flux ratio is used to derive the dust attenuation: this dust attenuation is found to increase with the luminosity of the galaxies and from z=0 to z=1. The slope of the UV continuum is found to be a very poor tracer of the dust attenuation in "normal" galaxies. Galaxies selected by their UV emission are found to be rather quiescent with a recent star formation rate equal to only 25-30% of the past averaged one. Galaxies selected in FIR appear slightly more active in star formation.

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V. Buat. 2004-11-23. The nearby universe observed in far-infrared and in ultraviolet: an analysis of the dust attenuation and the star formation activity. https://doi.org/10.1063/1.1913943

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