A Variety of Decays of Gamma-Ray Burst Pulses

Abstract

We find and study a variety of the spectral-temporal behavior during the decay phase of the light curve of long and bright pulse structures in gamma-ray bursts. It was earlier found that for about half of these decays, the instantaneous photon flux is consistent with a power law in time, where the photon flux $\propto$ 1/time. This decay behavior is a consequence of the validity of both a power law hardness-intensity correlation (HIC) and an exponential hardness-fluence correlation (HFC). Beside this behavior, we find that the other cases approximately behave as 1/(time)${}^3$. For a few of these latter decays, the two correlations (HIC and HFC) are constrained and found to be consistent with the light curve behavior. For these cases, the HIC is still a power law while the HFC is described by a generalized function. We study and describe these behaviors analytically and examine actual burst data from the complete catalog of the BATSE on the CGRO.

arXiv comment3 pages, to appear in "Gamma-Ray Burst in the Afterglow Era: 2nd Workshop" Rome - Italy October 17-20, 2000

Cited by in corpus (1)

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