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arXiv · 1308.2868

Revisiting the Light Curves of Gamma-ray Bursts in the Relativistic Turbulence Model

Abstract

Rapid temporal variability has been widely observed in the light curves of gamma-ray bursts (GRBs). One possible mechanism for such variability is related to the relativistic eddies in the jet. In this paper, we include the contribution of the inter-eddy medium together with the eddies to the gamma-ray emission. We show that the gamma-ray emission can either lead or lag behind the observed synchrotron emission, where the latter originates in the inter-eddy medium and provides most of seed photons for producing gamma-ray emission through the inverse-Compton scattering. As a consequence, we argue that the lead/lag found in non-stationary short-lived light curves may not reveal the intrinsic lead/lag of different emission components. In addition, our results may explain the lead of gamma-ray emission with respect to optical emission observed in GRB 080319B.

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Da-Bin Lin, Wei-Min Gu, Shu-Jin Hou, Tong Liu, Mou-Yuan Sun, Ju-Fu Lu. 2013-08-13. Revisiting the Light Curves of Gamma-ray Bursts in the Relativistic Turbulence Model. https://doi.org/10.1088/0004-637x%2F776%2F1%2F41

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