The observation of X-ray excesses greater than 5 sigma above an assummed model spectrum in about 15% of 86 bright bursts observed by BATSE has been verified in recent work. We have looked at a further 64 events, and observe the same behavior of a 15% excess rate for the statiscally-independent sample. We have examined the time-history of excesses for 10 bursts from the overall BATSE sample that had an overall greater than 8 sigma excess, in order to compare the behavior with other spectral parameters. In addition, we have looked at 17 bursts that exhibit no global excess, to determine the expected temporal variations in the BATSE low-energy data.
American Astronomical Society Meeting Abstracts
- Pub Date:
- December 1999