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Stability of an Ultra-Relativistic Blast Wave in an External Medium with a Steep Power-Law Density Profile

Xiaohu Wang·Abraham Loeb·Eli Waxman
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Abstract

We examine the stability of self-similar solutions for an accelerating relativistic blast wave which is generated by a point explosion in an external medium with a steep radial density profile of a power-law index > 4.134. These accelerating solutions apply, for example, to the breakout of a gamma-ray burst outflow from the boundary of a massive star, as assumed in the popular collapsar model. We show that short wavelength perturbations may grow but only by a modest factor <~ 10.

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Xiaohu Wang, Abraham Loeb, Eli Waxman. 2002-12-22. Stability of an Ultra-Relativistic Blast Wave in an External Medium with a Steep Power-Law Density Profile. https://doi.org/10.1086/377154

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