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A Variety of Decays of Gamma-Ray Burst Pulses

Felix Ryde·Roland Svensson
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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.

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Felix Ryde, Roland Svensson. 2001-02-23. A Variety of Decays of Gamma-Ray Burst Pulses. https://doi.org/10.1007/10853853_22

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