THE LOCATIONS OF GAMMA-RAY BURSTS MEASURED BY COMPTEL

The COMPTEL instrument on the Compton Gamma Ray Observatory is used to measure the locations of gamma-ray bursts through direct imaging of M eV photons. In a comprehensive search, we have detected and localized 29 bursts observed between 1991 April 19 and 1995 May 31. The average location accuracy of these events is 1.degrees 25 (1 sigma), including a systematic error of similar to 0.degrees 5, which is verified throu gh comparison with Interplanetary Network (IPN) timing annuli. The com bination of COMPTEL and IPN measurements results in locations for 26 o f the bursts with an average ''error box'' area of only similar to 0.3 deg(2) (1 sigma). We find that the angular distribution of COMPTEL bu rst locations is consistent with large-scale isotropy and that there i s no statistically significant evidence of small-angle autocorrelation s. We conclude that there is no compelling evidence for burst repetiti on since no more than two of the events (Or similar to 7% of the 29 bu rsts) could possibly have come from the same source. We also find that there is no significant correlation between the bust locations and ei ther Abell clusters of galaxies or radio-quiet quasars. Agreement betw een individual COMPTEL locations and IPN annuli places a lower limit o f similar to 100 AU (95% confidence) on the distance to the stronger b ursts.