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تسجيل مستخدم جديدEvidence for gravitational lensing of GRB 200716C
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Observationally, there are a small fraction GRBs prompt emission observed by Fermi/GBM that are composed of two pulses. Occasionally, the cosmological distance of GRB may be lensed when a high mass astrophysical object reside in path between GRB source and observer. In this paper, we are lucky to find out GRB 200716C with two-pulse emission which duration is a few seconds. We present a Bayesian analysis identifying gravitational lensing in both temporal and spectral properties, and calculate the time decay ($Delta tsim 1.92$ s) and magnification ($gammasim 1.5$) between those two pulses based on the temporal fits. One can roughly estimate the lens mass is about $2.38times 10^{5}~M_{odot}$ in the rest frame. If the first pulse of this GRB near triggered time is indeed gravitationally echoed by a second pulse, GRB 200716C may be a short GRB candidate with extended emission.
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