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Cosmological Uses of Gamma-Ray Bursts

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

Studies of the cosmic gamma-ray bursts (GRBs) and their host galaxies are starting to provide interesting or even unique new insights in observational cosmology. GRBs represent a new way of identifying a population of star-forming galaxies at cosmological redshifts. GRB hosts are broadly similar to the normal field galaxy populations at comparable redshifts and magnitudes, and indicate at most a mild luminosity evolution out to z ~ 1.5 - 2. GRB optical afterglows seen in absorption provide a powerful new probe of the ISM in dense, central regions of their host galaxies, complementary to the traditional studies using QSO absorbers. Some GRB hosts are heavily obscured, and provide a new way to select a population of cosmological sub-mm sources, and a novel constraint on the total obscured fraction of star formation over the history of the universe. Finally, detection of GRB afterglows at z > 6 may provide a unique way to probe the primordial star formation, massive IMF, early IGM, and chemical enrichment at the end of the cosmic reionization era.

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S. G. Djorgovski, S. R. Kulkarni, D. A. Frail, F. A. Harrison, J. S. Bloom, E. Berger, P. A. Price, D. Fox, A. M. Soderberg, R. Sari, S. Yost, A. A. Mahabal, S. M. Castro, R. Goodrich, F. Chaffee. 2003-01-31. Cosmological Uses of Gamma-Ray Bursts. https://arxiv.org/abs/astro-ph/0302004

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