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arXiv · 1109.5218

Shallow decay phase of the early X-ray afterglow from the external shock in wind environment

Hai-Dong Lei·Jin-Zhou Wang·Jing Lv·Yuan-Chuan Zou
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Abstract

The shallow decay phase of the early X-ray afterglow in gamma-ray bursts discovered by {\it Swift} is a widely discussed topic. As the spectral index does not change at the transferring of the shallow decay phase to a normal phase, it implies this transferring should be a dynamical change rather than a spectral evolution. We suggest both the shallow decay phase and the normal phase are from the external shock in a wind environment, while the transferring time is the deceleration time. We apply this model to GRBs 050319 and 081008, and find them can be well explained by choosing a proper set of parameters.

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Hai-Dong Lei, Jin-Zhou Wang, Jing Lv, Yuan-Chuan Zou. 2011-09-24. Shallow decay phase of the early X-ray afterglow from the external shock in wind environment. https://doi.org/10.1088/0256-307x%2F28%2F12%2F129801

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