General relativistic polarized radiative transfer with inverse Compton scatterings

TL;DR

This paper introduces { t radpol}, a comprehensive numerical scheme for polarized radiative transfer in curved spacetime, incorporating relativistic Compton scattering and other radiative processes, applicable to modeling emissions near black holes.

Contribution

The scheme is the first to include relativistic Compton scattering with polarization effects in a covariant radiative transfer framework.

Findings

Validated numerical algorithms for polarized light in curved spacetime.

Applied scheme to model broadband spectra around a supermassive black hole.

Demonstrated the scheme's applicability to realistic astrophysical scenarios.

Abstract

We present {\tt radpol} - a numerical scheme for integrating multifrequency polarized radiative transfer equations along rays propagating in a curved spacetime. The scheme includes radiative processes such as synchrotron emission, absorption, Faraday rotation and conversion, and, for the first time, relativistic Compton scatterings including effects of light polarization. The scheme is fully covariant and is applicable to model radio-$\gamma$-ray emission and its polarization from, e.g., relativistic jets and accretion flows onto black holes and other exotic objects described in alternative metric theories and modeled semi-analytically or with time-dependent magnetohydrodynamical simulations. We perform a few tests to validate the implemented numerical algorithms that handle light polarization in curved spacetime. We demonstrate application of the scheme to model broadband emission spectra from a relativistically hot, geometrically thick coronal-like inflow around a supermassive black hole where the disk model is realized in a general relativistic magnetohydrodynamical simulation.