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arXiv · 1410.8560

A novel paradigm for short gamma-ray bursts with extended X-ray emission

Luciano Rezzolla·Pawan Kumar
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Abstract

The merger of a binary of neutron stars provides natural explanations for many of the features of short gamma-ray bursts (SGRBs), such as the generation of a hot torus orbiting a rapidly rotating black hole, which can then build a magnetic jet and provide the energy reservoir to launch a relativistic outflow. Yet, this scenario has problems explaining the recently discovered long-term and sustained X-ray emission associated with the afterglows of a subclass of SGRBs. We propose a new model that explains how an X-ray afterglow can be sustained by the product of the merger and how the X-ray emission is produced before the corresponding emission in the gamma-band, although it is observed to follow it. Overall, our paradigm combines in a novel manner a number of well-established features of the emission in SGRBs and results from simulations. Because it involves the propagation of an ultra-relativistic outflow and its interaction with a confining medium, the paradigm also highlights a unifying phenomenology between short and long GRBs.

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Luciano Rezzolla, Pawan Kumar. 2015-01-21. A novel paradigm for short gamma-ray bursts with extended X-ray emission. https://doi.org/10.1088/0004-637x%2F802%2F2%2F95

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