A systematic description of shocks in gamma-ray bursts - II. Simulation

Abstract

In Paper I, we presented a detailed formulation of the relativistic shocks and synchrotron emission in the context of gamma-ray burst (GRB) physics. To see how well this model reproduces the observed characteristics of the GRBs and their afterglows, here we present the results of some simulations based on this model. They are meant to reproduce the prompt and afterglow emissions in some intervals of time during a burst. We show that this goal is achieved for both short and long GRBs and their afterglows, at least for part of the parameter space. Moreover, these results are evidence of the physical relevance of the two phenomenological models we have suggested in Paper I for the evolution of the active region - synchrotron emitting region in a shock. The dynamical active region model seems to reproduce the observed characteristics of prompt emissions and late afterglow better than the quasi-steady model which is more suitable for the onset of afterglows. Therefore, these simulations confirm the arguments presented in Paper I about the behaviour of these models based on their physical properties. © 2009 RAS.