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arXiv · 0905.0524

Optical Classification of Gamma-Ray Bursts in the Swift Era

A. J. van der Horst·C. Kouveliotou·N. Gehrels·E. Rol·R. A. M. J. Wijers·J. K. Cannizzo·J. Racusin·D. N. Burrows
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Abstract

We propose a new method for the classification of optically dark gamma-ray bursts (GRBs), based on the X-ray and optical-to-X-ray spectral indices of GRB afterglows, and utilizing the spectral capabilities of Swift. This method depends less on model assumptions than previous methods, and can be used as a quick diagnostic tool to identify optically sub-luminous bursts. With this method we can also find GRBs that are extremely bright at optical wavelengths. We show that the previously suggested correlation between the optical darkness and the X-ray/gamma-ray brightness is merely an observational selection effect.

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A. J. van der Horst, C. Kouveliotou, N. Gehrels, E. Rol, R. A. M. J. Wijers, J. K. Cannizzo, J. Racusin, D. N. Burrows. 2009-05-05. Optical Classification of Gamma-Ray Bursts in the Swift Era. https://doi.org/10.1088/0004-637x%2F699%2F2%2F1087

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