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arXiv · astro-ph/0202387

Efficient acceleration and radiation in Poynting flux powered GRB outflows

G. Drenkhahn·H. C. Spruit
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Abstract

We investigate the effects of magnetic energy release by local magnetic dissipation processes in Poynting flux-powered GRBs. For typical GRB parameters (energy and baryon loading) the dissipation takes place mainly outside the photosphere, producing non-thermal radiation. This process converts the total burst energy into prompt radiation at an efficiency of 10-50%. At the same time the dissipation has the effect of accelerating the flow to a large Lorentz factor. For higher baryon loading, the dissipation takes place mostly inside the photosphere, the efficiency of conversion of magnetic energy into radiation is lower, and an X-ray flash results instead of a GRB. We demonstrate these effects with numerical one-dimensional steady relativistic MHD calculations.

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G. Drenkhahn, H. C. Spruit. 2002-06-24. Efficient acceleration and radiation in Poynting flux powered GRB outflows. https://doi.org/10.1051/0004-6361%3A20020839

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