Francisco Virgili, Ying Qin, Bing Zhang, Enwei Liang
Using the gamma-ray bursts simultaneously detected by Swift/BAT and Fermi/GBM
we perform a joint spectral and temporal analysis of the prompt emission data.
Using derived spectral parameters, we confirm the rough correlation between the
BAT-band photon index Gamma^BAT and the peak spectral energy E_peak. With the
redshift known sub-sample, we derive the isotropic gamma-ray energy E_gamma,iso
and confirm the E_gamma,iso - E_peak,rest relation, with a larger scatter than
the Amati sample but consistent with another analysis by the GBM team. We also
compare the T_90 values derived in the GBM band with those derived in the BAT
band. We 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.
View original:
http://arxiv.org/abs/1112.4363
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