Updated Transfer Coefficients for Magnetized Plasmas
Andrew Marszewski2021, The Astrophysical Journal
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Abstract
Accurate radiative transfer coefficients (emissivities, absorptivities, and rotativities) are needed for modeling radiation from relativistically hot, magnetized plasmas such as those found in Event Horizon Telescope sources. Here we review, update, and correct earlier work on radiative transfer coefficients. We also describe an improved method for numerically evaluating rotativities and provide convenient fitting formulae for the relativistic κ distribution of electron energies. Here α S and ρ S are absorption and Faraday mixing coefficients, respectively, in the Stokes basis. We use a Cartesian coordinate system in the calculation of the transfer coefficients. We setẑ parallel to the magnetic field B. The observer angle θ is the angle between B and the photon wavevector k which we choose to lie in the x − z plane. Note that we have chosen a coordinate system (in the plasma rest frame) such that all Stokes U coefficients are zero.
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