Radiative Efficiencies Derived from the Swift Data : GRBs vs . XRFs , Long vs . Short
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چکیده
We systematically analyze the prompt emission and the early afterglow data of a sample of 31 GRBs detected by Swift before September 2005, and estimate the GRB radiative efficiency. BAT’s narrow band inhibits a precise determination of the GRB spectral parameters, and we have developed a method to estimate these parameters with the hardness ratio information. The shallow decay component commonly existing in early X-ray afterglows, if interpreted as continuous energy injection in the external shock, suggests that the GRB efficiency previously derived from the late-time X-ray data were not reliable. We calculate two radiative efficiencies using the afterglow kinetic energy EK derived at the putative deceleration time (tdec) and at the break time (tb) when the energy injection
منابع مشابه
GRB RADIATIVE EFFICIENCIES DERIVED FROM THE SWIFT DATA: GRBs VERSUS XRFs, LONG VERSUS SHORT
We systematically analyze the prompt emission and the early afterglow data of a sample of 31 GRBs detected by Swift before 2005 September and estimate the GRB radiative efficiency. BAT’s narrow band inhibits a precise determination of the GRB spectral parameters, and we have developed a method to estimate these parameters with the hardness ratio information. The shallow decay component commonly...
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تاریخ انتشار 2006