1 Introduction  

INTEGRAL (Inte rnational Ga mma R ay A strophysical L aboratory), an ESA $\gamma$-ray astronomy mission to be launched in 2001 [(Winkler 1997)], is expected to add significantly to the current understanding of GRBs. Its three coaligned high energy instruments (JEM-X, SPI, IBIS) use coded mask imaging technology to cover the energy range 3 keV through 10MeV; the optical monitor (OMC) supplements the coverage in the band of 500nm to 850nm (Table 1).

The good imaging capabilities of IBIS, its large field of view and high sensitivity around 100 keV, coupled with a continuous telemetry flow and a highly excentric 72h orbit allow for long uninterrupted observations and permit both fast and accurate localizations of GRB events.

 

Table 1:  Main instrument characteristics. FOV = (Partially coded) Field of View; FCFOV = Fully Coded Field of View; the angular resolution is given at FWHM; the spectral resolution is measured in ($\Delta E/E$)