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arXiv · astro-ph/0205144

X-ray Rich GRB, Photospheres and Variability

P. Meszaros·E. Ramirez-Ruiz·M. J. Rees·B. Zhang
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Abstract

We investigate the relationship between the quasi-thermal baryon-related photosphere in relativistic outflows, and the internal shocks arising outside them, which out to a limiting radius may be able to create enough pairs to extend the optically thick region. Variable gamma-ray light curves are likely to arise outside this limiting pair-forming shock radius, while X-ray excess bursts may arise from shocks occurring below it; a possible relation to X-ray flashes is discussed. This model leads to a simple physical interpretation of the observational gamma-ray variability-luminosity relation.

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P. Meszaros, E. Ramirez-Ruiz, M. J. Rees, B. Zhang. 2002-06-19. X-ray Rich GRB, Photospheres and Variability. https://doi.org/10.1086/342611

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