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arXiv · 1404.5319

Photospheric emission from long duration gamma-ray bursts powered by variable engines

Diego López-Cámara·Brian Morsony·Davide Lazzati
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Abstract

We present the results of a set of numerical simulations of long-duration gamma-ray burst jets aimed at studying the effect of a variable engine on the peak frequency of the photospheric emission. Our simulations follow the propagation of the jet inside the progenitor star, its break-out, and the subsequent expansion in the environment out to the photospheric radius. A constant and two step-function models are considered for the engine luminosity. We show that our synthetic light-curves follow a luminosity-peak frequency correlation analogous to the Golenetskii correlation found in long-duration gamma-ray burst observations. Within the parameter space explored, it appears that the central engine luminosity profile does not have a significant effect on the location of a gamma-ray burst in the Luminosity-peak frequency plane, bursts from different central engines being indistinguishable from each other.

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Diego López-Cámara, Brian Morsony, Davide Lazzati. 2014-05-20. Photospheric emission from long duration gamma-ray bursts powered by variable engines. https://doi.org/10.1093/mnras%2Fstu1016

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