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arXiv · astro-ph/0107535

The GRB Host Galaxies and Redshifts

S. G. Djorgovski·S. R. Kulkarni·J. S. Bloom·D. A. Frail·F. A. Harrison·T. J. Galama·D. Reichart·S. M. Castro·D. Fox·R. Sari·E. Berger·P. Price·S. Yost·R. Goodrich·F. Chaffee
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Abstract

Observations of GRB host galaxies and their environments in general can provide valuable clues about the nature of progenitors. Bursts are associated with faint, ~ 25 mag, galaxies at cosmological redshifts, ~ 1. The host galaxies span a range of luminosities and morphologies, and appear to be broadly typical for the normal, evolving, actively star-forming galaxy populations at comparable redshifts and magnitudes, but may have somewhat elevated SFR per unit luminosity. There are also spectroscopic hints of massive star formation, from the ratios of [Ne III] and [O II] lines. The observed, unobscured star formation rates are typically a few M_sun/yr, but a considerable fraction of the total star formation in the hosts may be obscured by dust. A census of detected optical afterglows provides a powerful new handle on the obscured fraction of star formation in the universe; the current results suggest that at most a half of the massive star formation was hidden by dust.

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S. G. Djorgovski, S. R. Kulkarni, J. S. Bloom, D. A. Frail, F. A. Harrison, T. J. Galama, D. Reichart, S. M. Castro, D. Fox, R. Sari, E. Berger, P. Price, S. Yost, R. Goodrich, F. Chaffee. 2001-07-27. The GRB Host Galaxies and Redshifts. https://doi.org/10.1007/10853853_60

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