It has recently been suggested that the BATSE gamma-ray burst catalog contains several groups of bursts clustered in space (Quashnock and Lamb, MNRAS 265, L59, 1993) or in space and time (Wang and Lingenfelter, ApJ 416, L13, 1993), which provide evidence that a substantial fraction of the classical GRB sources repeat. If this is true, it may be taken as strong evidence against cosmological models of burst sources. We apply the network synthesis method to these events to test the repeating burst hypothesis. It consists of defining a grid of RA and Dec values, and for each BATSE detection of a burst from a repeater, predicting the arrival time of the burst at Ulysses and concatenating individual stretches of Ulysses data. This concatenated time history is then cross-correlated with the corresponding concatenated BATSE time history and tested for the presence of a statistically significant correlation coefficient. Although we find no evidence for repeating sources, the method must be refined and applied under more general conditions before reaching any definite conclusions about the existence of classical repeating GRB sources.
American Astronomical Society Meeting Abstracts
- Pub Date:
- December 1994