In this study we have developed a method that allows us to search for GRBs common to two catalogues of sources, each one based on a different instrument. The method makes use of the GRBs detected simultaneously by both experiments, so it is necessary that the experiments overlap in time. We have applied the method to the WATCH (WATCH/GRANAT + WATCH/EURECA) and BATSE (BATSE 4B + bursts detected after August 1996) catalogues.
We conclude that there is no evidence of recurrent activity of WATCH bursts in the BATSE sample. We claim (with a 94% confidence level) that no more than a 15.8% of the 57 GRBs detected by WATCH are present in the sample of 1905 BATSE bursts (excluding the simultaneous bursts). However, the possibility of finding repeaters in each single catalogue cannot be ruled out. Our results support models which do not predict repetitions of GRBs (for instance the merging of neutron stars at cosmological distances).
© European Southern Observatory (ESO) 1998
Online publication: July 7, 1998