Evidence for “Chain Reaction” in the Time Profiles of Gamma-Ray Bursts

Abstract

Although the time profiles of gamma ray bursts (GRBs) show extremely diverse behavior, their average statistical properties such as the average peak-aligned profile and the auto-correlation function show simple stretched-exponential behavior. This could indicate that the diversity of all bursts is just due to different random realizations of the same simple stochastic process where the process is scale invariant in time. We illustrate how both the diversity of GRB time profiles and some important average statistical properties can be reproduced in this way using a simple toy model for a stochastic pulse avalanche, which behaves as a chain reaction in a near-critical regime. We suggest that one possibility for the underlying physical process for generating GRBs could be a chain detonation in which reconnecting magnetic turbulent features trigger each other.