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arXiv · 1112.4363

Spectral and temporal analysis of the joint Swift/BAT-Fermi/GBM GRB sample

Francisco Virgili·Ying Qin·Bing Zhang·Enwei Liang
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Abstract

Using the gamma-ray bursts simultaneously detected by Swift/BAT and Fermi/GBM we performed a joint spectral and temporal analysis of the prompt emission data and confirm the rough correlation between the BAT-band photon index Gamma_BAT and the peak spectral energy Epeak. With the redshift known sub-sample, we derived the isotropic gamma-ray energy E_gamma,iso and also confirm the E_gamma,iso - Epeak,rest relation, with a larger scatter than the Amati sample but consistent with GBM team analyses. We also compare the T_90 values derived in the GBM band with those derived in the BAT band and find that for long GRBs the BAT T_90 is usually longer than the GBM T_90, while for short GRBs the trend reverses. This is consistent with the soft/hard nature of long/short GRBs and suggests the importance of an energy-dependent temporal analysis of GRBs.

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Francisco Virgili, Ying Qin, Bing Zhang, Enwei Liang. 2012-06-04. Spectral and temporal analysis of the joint Swift/BAT-Fermi/GBM GRB sample. https://doi.org/10.1111/j.1365-2966.2012.21411.x

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