Effects of a low electron distribution cutoff on multiwavelength spectra and light curves of GRB afterglows

TL;DR

This paper explores how a low maximum electron energy affects the multiwavelength spectra and light curves of GRB afterglows, revealing X-ray plateaus due to spectral component transitions.

Contribution

It introduces a model allowing the maximum electron energy to vary freely, demonstrating its impact on GRB afterglow light curves and spectra.

Findings

X-ray light curves exhibit a plateau when maximum electron energy is low.

Transition from synchrotron to synchrotron self-Compton dominates X-ray band.

Model explains observed features in GRB afterglow light curves.

Abstract

Aims: We investigate the behavior of the frequency-centered light curves expected within the standard model of Gamma Ray Bursts allowing the maximum electron energy to be a free parameter permitted to take low values. Methods: We solve the spatially averaged kinetic equations which describe the simultaneous evolution of particles and photons, obtaining the multi-wavelength spectra as a function of time. From these we construct the frequency-centered light curves giving emphasis in the X-ray and optical bands. Results: We show that in cases where the maximum electron energy takes low values, the produced X-ray light curves show a plateau as the synchrotron component gives its place to the Synhro Self-Compton one in the X-ray band.