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arXiv · 1401.7283

GRB 131231A: Implications of the GeV emission

Bin Liu·Wei Chen·Yun-Feng Liang·Bei Zhou·Hao-Ning He·Pak-Hin Thomas Tam·Lang Shao·Zhi-Ping Jin·Yi-Zhong Fan·Da-Ming Wei
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Abstract

GRB 131231A was detected by the Large Area Telescope onboard Fermi Space Gamma-ray Telescope. The high energy gamma-ray ($> 100$ MeV) afterglow emission spectrum is $F_ν\propto ν^{-0.54\pm0.15}$ in the first $\sim 1300$ s after the trigger and the most energetic photon has an energy $\sim 62$ GeV arriving at $t\sim 520$ s. With reasonable parameters of the GRB outflow as well as the density of the circum-burst medium, the synchrotron radiation of electrons or protons accelerated at an external forward shock have difficulty accounting for the data. The synchrotron self-Compton radiation of the forward shock-accelerated electrons, instead, can account for both the spectrum and temporal behavior of the GeV afterglow emission. We also show that the prospect for detecting GRB 131231A$-$like GRBs with Cherenkov Telescope Array (CTA) is promising.

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Bin Liu, Wei Chen, Yun-Feng Liang, Bei Zhou, Hao-Ning He, Pak-Hin Thomas Tam, Lang Shao, Zhi-Ping Jin, Yi-Zhong Fan, Da-Ming Wei. 2014-04-24. GRB 131231A: Implications of the GeV emission. https://doi.org/10.1088/2041-8205%2F787%2F1%2Fl6

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