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arXiv · 1308.5157

The beaming pattern of External Compton Emission from relativistic outflows

S. R. Kelner·E. Lefa·F. M. Rieger·F. A. Aharonian
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Abstract

The beaming pattern of radiation emitted by a relativistically moving source like jets in microquasars, AGN and GRBs, is a key issue for understanding of acceleration and radiation processes in these objects. In this paper we introduce a formalism based on a solution of the photon transfer equation to study the beaming patterns for emission produced by electrons accelerated in the jet and upscattering photons of low-energy radiation fields of external origin (the so-called External Compton scenario). The formalism allows us to treat non-stationary, non-homogeneous and anisotropic distributions of electrons, but assuming homogeneous/isotropic and non-variable target photon fields. We demonstrate the non-negligible impact of the anisotropy in the electron distribution on angular and spectral characteristics of the EC radiation.

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S. R. Kelner, E. Lefa, F. M. Rieger, F. A. Aharonian. 2013-08-23. The beaming pattern of External Compton Emission from relativistic outflows. https://doi.org/10.1088/0004-637x%2F785%2F2%2F141

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