ESA Science & Technology - GRB 040403: A faint X-ray rich gamma-ray burst discovered by INTEGRAL

Publication date: 02 March 2005

Authors: Mereghetti, S., et al.

Journal: A&A
Volume: 433
Issue: 2
Page: 113-116
Year: 2005

Copyright: ESO 2005

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 h after the burst, indicates a rather faint afterglow, similar to those seen in other relatively soft and faint bursts.