2002/06/30 by C. Barraud, J-F. Olive, J. P. Lestrade +27 · 1 citation
Physics and Astronomy · #astro-ph
paper · pdf · doi:10.1051/0004-6361:20030074
14 pages, 43 figures, accepted for publication in Astronomy and Astrophysics
arxiv created 2003/01/13 · arxiv updated 2009/12/01
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, epeak . We then discuss the existence and nature of the recently discovered X-Ray Flashes and their relationship with classical GRBs.