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Synchrotron and SSC Emission and the Blast-Wave Model of Gamma-Ray Bursts

J. Chiang·C. D. Dermer
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Abstract

We investigate the dynamics and radiation from a relativistic blast-wave which decelerates as it sweeps up ambient matter. The bulk kinetic energy of the blast-wave shell is converted into internal energy by the process of accreting external matter. If it takes the form of non-thermal electrons and magnetic fields, then this internal energy will be emitted as synchrotron and synchrotron self-Compton radiation. We perform analytic and numerical calculations for the deceleration and radiative processes and present time-resolved spectra throughout the evolution of the blast-wave. We also examine the dependence of the burst spectra and light curves on various parameters describing the magnetic field and non-thermal electron distributions. We find that for bursts such as GRB~910503, GRB~910601 and GRB~910814, the spectral shapes of the prompt gamma-ray emission at the peaks in $νF_ν$ strongly constrain the magnetic fields in these bursts to be well below ($\la 10^{-2}$) the equipartition values. These calculations are also considered in the context of the afterglow emission from the recently detected gamma-ray burst counterparts.

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J. Chiang, C. D. Dermer. 1998-03-31. Synchrotron and SSC Emission and the Blast-Wave Model of Gamma-Ray Bursts. https://doi.org/10.1086/306789

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