Prompt and afterglow emission from the X - ray rich GRB 981226 observed with
نویسندگان
چکیده
We discuss observations of the prompt X– and γ–ray emission and X–ray afterglow from GRB981226. This event has the weakest gamma-ray peak flux detected with the BeppoSAX Gamma-Ray Burst Monitor. It shows an isolated X-ray precursor and the highest X-ray to gamma-ray fluence ratio measured thus far with the BeppoSAX Wide Field Cameras. The event was followed up with the BeppoSAX Narrow Field Instruments, and the X-ray afterglow was detected up to 10 keV. The afterglow flux is observed to rise from a level below the sensitivity of the MECS/LECS telescopes up to a peak flux of (5±1) × 10 −13 erg cm −2 s −1 in the 2-10 keV energy band. This rise is followed by a decline according to a power law with index of 1.31 +0.44 −0.39. We discuss these results in the light of the current GRB models. – 2 –
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تاریخ انتشار 2000