THE CONTINUUM SPECTRAL CHARACTERISTICS OF GAMMA-RAY BURSTS OBSERVED BY BATSE

Distributions of the continuum spectral characteristics of 260 bursts in the first BATSE catalog are presented. The data are derived from fl ux ratios calculated from the BATSE Large Area Detector (LAD) four-cha nnel discriminator data. The data are converted from counts to photons using a direct spectral inversion technique to remove the effects of atmospheric scattering and the energy dependence of the detector angul ar response. Although there are intriguing clusterings of bursts in th e spectral hardness ratio distributions, no evidence for the presence of distinct burst classes based on spectral hardness ratios alone is f ound. All subsets of bursts selected for their spectral characteristic s in this analysis exhibit spatial distributions consistent with isotr opy. The spectral diversity of the burst population appears to be caus ed largely by the highly variable nature of the burst production mecha nisms themselves.