WFC + GRBM detections of GRB

The GRBM has become world wide popular in the last two years thanks to the simultaneous detection of some (15 up to now) GRB with the WFC and the consequent capability of quickly locating the GRB in the sky with a 3 arc-minutes accuracy. The co-alignment of GRBM detectors LS1 and LS3 offers the possibility not only to precisely localize GRBs and detect very faint X-ray afterglow emission of a GRB event down to $1 \times 10^{-13}\, {\rm erg/(cm^2\,s)}$, but also to perform in a broad energy band (1.5-700 keV) temporal and spectral study of those primary events from which afterglow emission is originated. In chapter 5 we show results of GRBM joint data analysis spectral data analysis of GRB.
The first simultaneous detection of a GRB was GRB960720, discovered by means of off-line screening of GRBM and WFC data. After this discovery, an operative strategy was developed in order to examine on-line each orbit the WFC light curves in correspondence of GRBM trigger. This search has been successively extend to trigger from GRB experiments other than the GRBM (e.g. BATSE triggers). Up to now, the GRB simultaneously detected by the two instruments are 15 (Tab. 5.1), the last (but not least) being the very recent and interesting GRB990123.