IMPROVED LIMITS ON GAMMA-RAY BURST REPETITION FROM BATSE

We tighten previous upper limits on gamma-ray burst repetition by anal yzing the angular power spectrum of the BATSE 3B catalog of 1122 burst s. At 95% confidence, we find that no more than 2% of all observed bur sts can be labeled as repeaters, even if no sources are observed to re peat more than once. If a fraction f of all observed bursts can be lab eled as repeaters that are observed to burst nu times each, then all m odels with (nu - 1)f greater than or equal to 0.05 are ruled out at 99 % confidence, as compared to the best previous 99% limit (nu - 1)f gre ater than or equal to 0.27. At 95% confidence, our new limit is (nu - 1)f greater than or equal to 0.02. Thus, even a cluster of six events from a single source would have caused excess power above that present in the 3B catalog. We conclude that the current BATSE data are consis tent with no repetition of classical gamma-ray bursts and that any rep eater model is severely constrained by the near-perfect isotropy of th eir angular distribution.