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arXiv · astro-ph/9906145

Quasi-Thermal Comptonization and GRBs

Gabriele Ghisellini·Annalisa Celotti
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Abstract

Quasi-thermal Comptonization is an attractive alternative to the synchrotron process to explain the spectra of GRBs, even if we maintain other important properties of the internal shock scenario, implying a compact emitting region and an equipartition magnetic field. Photon-photon absorption and electron-positron pairs can play a crucial role: this process may lock the effective temperature in a narrow range and may be the reason why burst spectra have high energy cut-offs close to the rest mass-energy of the electron. If the progenitors of GRB are hypernovae, the circum-burst matter is dominated by the wind of the pre-hypernova star. The presence of this dense material has strong effects on the generation of the radiation of the burst and its afterglow.

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Gabriele Ghisellini, Annalisa Celotti. 1999-06-08. Quasi-Thermal Comptonization and GRBs. https://doi.org/10.1051/aas%3A1999339

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