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arXiv · 1907.08806

Spectral Lag for a Radiating Jet Shell with a High Energy Cut-off Radiation Spectrum

Shen-Shi Du·Da-Bin Lin·Rui-Jing Lu·Rui-Quan Li·Ying-Ying Gan·Jia Ren·Xiang-Gao Wang·En-Wei Liang
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Abstract

Recent research shows that the spectral lag is closely related to the spectral evolution in GRBs. In this paper, we study the spectral lag for a radiating jet shell with a high-energy cut-off radiation spectrum. For the jet shell with a cut-off power-law spectrum, the spectral lag monotonically increases with the photon energy and levels off at a certain photon energy. It is the same for the jet shell with a Band cut-off spectrum (Bandcut). However, a turn-over from the positive lags to negative lags appears in the high-energy range for the jet shell with Bandcut, which is very similar to that observed in GRB~160625B. The dependence of the spectral lags on the spectral shape/evolution are studied in details. In addition, the spectral lag behavior observed in GRB~160625B is naturally reproduced based on our theoretical outcome.

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Shen-Shi Du, Da-Bin Lin, Rui-Jing Lu, Rui-Quan Li, Ying-Ying Gan, Jia Ren, Xiang-Gao Wang, En-Wei Liang. 2019-07-20. Spectral Lag for a Radiating Jet Shell with a High Energy Cut-off Radiation Spectrum. https://doi.org/10.3847/1538-4357%2Fab33fe

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