Behaviors of X-ray Dust-Scattering and Implications for X-ray Afterglows of Gamma-Ray Bursts
نویسنده
چکیده
The afterglows of gamma-ray bursts (GRBs) have been commonly assumed to be due to shocks sweeping up circum-stellar medium. However, most of them have been found to be hosting 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 behaviors of X-ray dust-scattering in GRBs. We find that the features of some X-ray afterglows about minutes to days after the gamma-ray triggers are consistent with 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 in this dustscattering-driven emission model. Subject headings: dust, extinction — gamma rays: bursts — interstellar medium — X-rays: general
منابع مشابه
Behavior of X-Ray Dust Scattering and Implications for X-Ray Afterglows of Gamma-Ray Bursts
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 afterg...
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