Session B16 - Neutrino and Gamma Ray Astrophysics.
MIXED session, Saturday morning, April 29
202C, Convention Center
Observing gamma-ray bursts (GRBs) in the TeV energy range can be extremely valuable in providing insight into GRB radiation mechanisms and in constraining source distances. The Milagrito detector was an air shower array which used the water Cherenkov technique to search for TeV sources. Unlike other detectors which have attempted to search for GRBs at TeV energies, Milagrito combined the characteristics of a low energy threshold, a large field of view, and a high duty cycle, making it a practical instrument for detecting gammay ray events which lasted but fleetingly and which were unpredictable in both time and position of occurrence. Data from this detector was analyzed to look for TeV emission from 54 BATSE GRBs which were in the field of view of the Milagrito detector during its lifetime (January 1997 to May 1998). Results from this analysis, including evidence for TeV emission from GRB 970417a, will be presented.