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Behavior of X-Ray Dust Scattering and Implications for X-Ray Afterglows of Gamma-Ray Bursts

L. Shao·Z. G. Dai
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Abstract

The afterglows of gamma-ray bursts (GRBs) have commonly been assumed to be due to shocks sweeping up the circum-stellar medium. However, most GRBs have been found in dense star-forming regions where a significant fraction of the prompt X-ray emission can be scattered by dust grains. Here we revisit the behavior of dust scattering of X-rays in GRBs. We find that the features of some X-ray afterglows from minutes to days after the gamma-ray triggers are consistent with the scattering of prompt X-ray emission from GRBs off host dust grains. This implies that some of the observed X-ray afterglows (especially those without sharp rising and decaying flares) could be understood with a dust-scattering--driven emission model.

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L. Shao, Z. G. Dai. 2007-03-30. Behavior of X-Ray Dust Scattering and Implications for X-Ray Afterglows of Gamma-Ray Bursts. https://doi.org/10.1086/513139

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