English

Dynamical Evolution of an Ultra-relativistic Fireball Colliding with a Freely Expanding Gas

High Energy Astrophysical Phenomena 2015-06-23 v1

Abstract

We investigate the hydrodynamical evolution of an ultra-relativistic fireball colliding with a freely expanding gas. The hydrodynamical interaction of the fireball and the gas results in the formation of a geometrically thin shell. We study the dynamical evolution of the shell by an analytical way and perform a numerical simulation equipped with an adaptive mesh refinement to investigate the internal structure of the shell. The shocked gas can give rise to bright emission in the X-ray and gamma-ray energy range. We propose that the breakout emission from the forward shock and the photospheric emission from the reverse-shocked fireball contribute to early gamma-ray emission from gamma-ray bursts.

Keywords

Cite

@article{arxiv.1409.6826,
  title  = {Dynamical Evolution of an Ultra-relativistic Fireball Colliding with a Freely Expanding Gas},
  author = {Akihiro Suzuki and Toshikazu Shigeyama},
  journal= {arXiv preprint arXiv:1409.6826},
  year   = {2015}
}

Comments

15 pages, 9 figures, accepted for publication in ApJ