SPECTRAL EVOLUTION OF GRB PULSES

We perform time-resolved spectral analysis on 26 multi-pulse BATSE GRB s. By fixing two parameters of a a-parameter fit to the time-integrate d values, we achieve a robust spectral hardness measure and physical f luxes. 28 pulse decay phases in 15 GRBs show significant correlation b etween peak power energy and instantaneous energy flux (characterized by F-E proportional to E(p)(1.7)). We compare peak energy fluxes, peak hardnesses, and pulse durations and separation for pulse pairs in our sample. There may be some indication of a ''recovery timescale'' for the bursters' energy source or environment.