GRB 021125: The first GRB imaged by INTEGRAL

In the late afternoon of November 25th, 2002 a gamma-ray burst (GRB) was detected in the partially coded field of view (about 7.3degrees from the centre) of the imager IBIS on board the INTEGRAL satellite. The instruments on-board INTEGRAL allowed, for the first time, the observation of the prompt gamma-ray emission over a broad energy band from 15 to 500 keV. GRB 021125 lasted similar to 24 s with a mean flux of similar to 5.0 photons cm(-2) s(-1) in the 20 - 500 keV energy band, and a fluence of similar to 4.8 x 10(-5) erg cm(-2) in the same energy band. Here we report the analysis of the data from the imager IBIS and the spectrometer SPI.