van Eerten 2009 数值模拟结果现实密度跳变不能解释X-ray flare

主要内容:
只能是中央引擎

精彩摘抄:


文章信息:

· Find Similar Abstracts (with default settings below)

· arXiv e-print (arXiv:0906.3629)

· References in the Article

·

· Translate This Page

Title:		No visible optical variability from a relativistic blast wave encountering a wind-termination shock
Authors:		van Eerten, H. J.; Meliani, Z.; Wijers, R. A. M. J.; Keppens, R.
Publication:		eprint arXiv:0906.3629
Publication Date:		06/2009
Origin:		ARXIV
Keywords:		Astrophysics - High Energy Astrophysical Phenomena
Comment:		4 figures, submitted to MNRAS letters
Bibliographic Code:		2009arXiv0906.3629V

Abstract

Gamma-ray burst afterglow flares and rebrightenings of the optical and X-ray light curve have been attributed to both late time inner engine activity and density changes in the medium surrounding the burster. To test the latter, we study the encounter between the relativistic blast wave from a gamma-ray burster and a stellar wind termination shock. The blast wave is simulated using a high performance adaptive mesh relativistic hydrodynamics code, AMRVAC, and the synchrotron emission is analyzed in detail with a separate radiation code. We find no bump in the resulting light curve, not even for very high density jumps. Furthermore, by analyzing the contributions from the different shock wave regions we are able to establish that it is essential to resolve the blast wave structure in order to make qualitatively correct predictions on the observed output and that the contribution from the reverse shock region will not stand out, even when the magnetic field is increased in this region by repeated shocks. This study resolves a controversy in recent literature.

---

Bibtex entry for this abstract Preferred format for this abstract (see Preferences)