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Register a new userPhysics of non-dissipative ultrarelativistic photospheres
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Added by
Gregory V. Vereshchagin
Publication date
2013
fields
Physics
and research's language is
English
Authors
Gregory Vereshchagin
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Recent observations, especially by the Fermi satellite, point out the importance of the thermal component in GRB spectra. This fact revives strong interest in photospheric emission from relativistic outflows. Early studies already suggested that the observed spectrum of photospheric emission from relativistically moving objects differs in shape from the Planck spectrum. However, this component appears to be subdominant in many GRBs and the origin of the dominant component is still unclear. One of the popular ideas is that energy dissipation near the photosphere may produce a non-thermal spectrum and account for such emission. Before considering such models, though, one has to determine precise spectral and timing characteristics of the photospheric emission in the simplest possible case. Hence this paper focuses on various physical effects which make the photospheric emission spectrum different from the black body spectrum and quantifies them.
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