Spectral analysis of 35 GRBs/XRFs observed with HETE-2/FREGATE

C. Barraud; J-F. Olive; J. P. Lestrade; J-L. Atteia; K. Hurley; G. Ricker; D. Q. Lamb; N. Kawai; M. Boer; J-P. Dezalay; G. Pizzichini; R. Vanderspek; G. Crew; J. Doty; G. Monelly; J. Villasenor; N. Butler; A. Levine; A. Yoshida; Y. Shirasaki; T. Sakamoto; T. Tamagawa; K. Torii; M. Matsuoka; E. E. Fenimore; M. Galassi; T. Tavenner; T. Q. Donaghy; C. Graziani; J. G. Jernigan

doi:10.1051/0004-6361:20030074

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Spectral analysis of 35 GRBs/XRFs observed with HETE-2/FREGATE

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Abstract

We present a spectral analysis of 35 GRBs detected with the HETE-2 gamma-ray detectors (the FREGATE instrument) in the energy range 7-400 keV. The GRB sample analyzed is made of GRBs localized with the Wide Field X-ray Monitor onboard HETE-2 or with the GRB Interplanetary Network. We derive the spectral parameters of the time-integrated spectra, and present the distribution of the low-energy photon index, alpha, and of the peak energy, e_peak . We then discuss the existence and nature of the recently discovered X-Ray Flashes and their relationship with classical GRBs.

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C. Barraud, J-F. Olive, J. P. Lestrade, J-L. Atteia, K. Hurley, G. Ricker, D. Q. Lamb, N. Kawai, M. Boer, J-P. Dezalay, G. Pizzichini, R. Vanderspek, G. Crew, J. Doty, G. Monelly, J. Villasenor, N. Butler, A. Levine, A. Yoshida, Y. Shirasaki, T. Sakamoto, T. Tamagawa, K. Torii, M. Matsuoka, E. E. Fenimore, M. Galassi, T. Tavenner, T. Q. Donaghy, C. Graziani, J. G. Jernigan. 2003-01-13. Spectral analysis of 35 GRBs/XRFs observed with HETE-2/FREGATE. https://doi.org/10.1051/0004-6361%3A20030074

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