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تسجيل مستخدم جديدDecay properties of the X-ray afterglows of Gamma-ray bursts
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B. Gendre
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We present a set of seventeen Gamma-Ray Bursts (GRBs) with known redshifts and X-ray afterglow emission. We apply cosmological corrections in order to compare their fluxes normalized at a redshift of 1. Two classes of GRB can be defined using their X-ray afterglow light curves. We show that the brightest afterglows seem to decay faster than the dimer ones. We also point out evidences for a possible flux limit of the X-ray afterglow depending on the time elapsed since the burst. We try to interpret these observations in the framework of the canonical fireball model of GRB afterglow emission.
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I will review the constraints set by X-ray measurements of afterglows on several issues of GRB, with particular regard to the fireball model, the environment, the progenitor and dark GRB.
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