The blue colors of Gamma-ray burst host galaxies

E. Le Floc'h; P. -A. Duc; I. F. Mirabel

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arXiv · astro-ph/0211252

The blue colors of Gamma-ray burst host galaxies

E. Le Floc'h·P. -A. Duc·I. F. Mirabel

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Abstract

There is now an increasing number of evidence supporting the idea that the cosmic Gamma-ray Bursts (GRBs) originate from the collapse of massive stars in distant star-forming galaxies. Because GRBs are likely detectable up to very high redshift, and because the gamma-rays are not attenuated by intervening columns of gas and dust, these phenomena thus offer a unique perspective to probe the star formation in the early Universe independently of the biases associated with dust extinction. We report on the R-K colors of the GRB host galaxies. We find that they are very blue sources, with colors comparable to those of the faint blue star-forming galaxies at high redshift.

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E. Le Floc'h, P. -A. Duc, I. F. Mirabel. 2002-11-12. The blue colors of Gamma-ray burst host galaxies. https://arxiv.org/abs/astro-ph/0211252

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