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Relativistic Jets from Collapsars

Miguel A. Aloy·Ewald Mueller·Jose M. Ibanez·Jose M. Marti·Andrew MacFadyen
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Abstract

We have studied the relativistic beamed outflow proposed to occur in the collapsar model of gamma-ray bursts. A jet forms as a consequence of an assumed energy deposition of $\sim 10^{50}- 10^{51}$ erg/s within a $30^{\circ}$ cone around the rotation axis of the progenitor star. The generated jet flow is strongly beamed ($\la$ few degrees) and reaches the surface of the stellar progenitor (r $\approx 3 10^{10} $cm) intact. At break-out the maximum Lorentz factor of the jet flow is about 33. Simulations have been performed with the GENESIS multi-dimensional relativistic hydrodynamic code.

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Miguel A. Aloy, Ewald Mueller, Jose M. Ibanez, Jose M. Marti, Andrew MacFadyen. 1999-10-26. Relativistic Jets from Collapsars. https://arxiv.org/abs/astro-ph/9910466

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