The influence of jet geometry on light curves and spectra of GRB afterglows

TL;DR

This paper investigates how jet geometry affects the observed light curves and spectra of gamma-ray burst (GRB) afterglows by performing detailed relativistic radiative transfer calculations within a shock model.

Contribution

It introduces a comprehensive numerical method to compute GRB afterglow spectra and light curves considering jet geometry and relativistic effects.

Findings

Jet geometry significantly influences afterglow light curves.

Relativistic transfer calculations provide accurate modeling of observed spectra.

The model helps interpret diverse GRB afterglow observations.

Abstract

We have performed detailed calculations of spectra and light curves of GRB afterglows assuming that the observed GRBs can have a jet geometry. The calculations are based on an expanding relativistic shock GRB afterglow model where the afterglow is the result of synchrotron radiation of relativistic electrons with power-law energy distribution at the front of external shock being decelerated in a circumstellar medium. To determine the intensity on the radiation surface we solve numerically the full time-, angle-, and frequency-dependent special relativistic transfer equation in the comoving frame using the method of long characteristics.