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arXiv · 1502.07134

Numerical Models of Blackbody-Dominated GRBs

Carlos F. Cuesta-Martínez·Miguel-Ángel Aloy·Petar Mimica·Christina C. Thöne·Antonio de Ugarte-Postigo
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Abstract

Blackbody-dominated (BBD) gamma-ray bursts (GRBs) are events characterized by the absence of a typical afterglow, long durations and the presence of a significant thermal component following the prompt gamma-ray emission. GRB 101225A (the `Christmas burst') is a prototype of this class. A plausible progenitor system for it, and for the BBD-GRBs, is the merger of a neutron star (NS) and a helium core of an evolved, massive star. Using relativistic hydrodynamic simulations we model the propagation of an ultrarelativistic jet through the enviroment created by such a merger and we compute the whole radiative signature, both thermal and non-thermal, of the jet dynamical evolution. We find that the thermal emission originates from the interaction between the jet and the hydrogen envelope ejected during the NS/He merger.

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Carlos F. Cuesta-Martínez, Miguel-Ángel Aloy, Petar Mimica, Christina C. Thöne, Antonio de Ugarte-Postigo. 2015-02-25. Numerical Models of Blackbody-Dominated GRBs. https://arxiv.org/abs/1502.07134

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