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arXiv · astro-ph/0412012

GRB 040403: a faint X-ray rich Gamma-ray Burst discovered by INTEGRAL

S. Mereghetti·D. Gotz·M. I. Andersen·A. Castro-Tirado·F. Frontera·J. Gorosabel·D. H. Hartmann·J. Hjorth·R. Hudec·K. Hurley·G. Pizzichini·N. Produit·A. Tarana·M. Topinka·P. Ubertini·A. de Ugarte
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Abstract

GRB 040403 is one of the faintest gamma-ray bursts for which a rapid and accurate localization has been obtained. Here we report on the gamma-ray properties of this burst, based on observations with the IBIS instrument aboard INTEGRAL, and the results of searches for its optical afterglow. The steep spectrum (power law photon index = 1.9 in the 20-200 keV range) implies that GRB 040403 is most likely an X-ray rich burst. Our optical limit of R > 24.2 at 16.5 hours after the burst, indicates a rather faint afterglow, similar to those seen in other relatively soft and faint bursts.

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S. Mereghetti, D. Gotz, M. I. Andersen, A. Castro-Tirado, F. Frontera, J. Gorosabel, D. H. Hartmann, J. Hjorth, R. Hudec, K. Hurley, G. Pizzichini, N. Produit, A. Tarana, M. Topinka, P. Ubertini, A. de Ugarte. 2004-12-01. GRB 040403: a faint X-ray rich Gamma-ray Burst discovered by INTEGRAL. https://doi.org/10.1051/0004-6361%3A20042030

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