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Evidence for a Canonical GRB Afterglow Light Curve in the Swift/XRT Data

J. A. Nousek·C. Kouveliotou·D. Grupe·K. Page·J. Granot·E. Ramirez-Ruiz·S. K. Patel·D. N. Burrows·V. Mangano·S. Barthelmy·A. P. Beardmore·S. Campana·M. Capalbi·G. Chincarini·G. Cusumano·A. D. Falcone·N. Gehrels·P. Giommi·M. Goad·O. Godet·C. Hurkett·J. A. Kennea·A. Moretti·P. O'Brien·J. Osborne·P. Romano·G. Tagliaferri·A. Wells
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Abstract

We present new observations of the early X-ray afterglows of the first 27 gamma-ray bursts (GRBs) detected with the Swift X-ray Telescope (XRT). The early X-ray afterglows show a canonical behavior, where the light curve broadly consists of three distinct power law segments: (i) an initial very steep decay (t^{-alpha} with 3 4, and augments the already severe requirements for the efficiency of the prompt gamma-ray emission.

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J. A. Nousek, C. Kouveliotou, D. Grupe, K. Page, J. Granot, E. Ramirez-Ruiz, S. K. Patel, D. N. Burrows, V. Mangano, S. Barthelmy, A. P. Beardmore, S. Campana, M. Capalbi, G. Chincarini, G. Cusumano, A. D. Falcone, N. Gehrels, P. Giommi, M. Goad, O. Godet, C. Hurkett, J. A. Kennea, A. Moretti, P. O'Brien, J. Osborne, P. Romano, G. Tagliaferri, A. Wells. 2006-01-27. Evidence for a Canonical GRB Afterglow Light Curve in the Swift/XRT Data. https://doi.org/10.1086/500724

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