Strong-gravity effects acting on polarization from orbiting spots

TL;DR

This paper investigates how strong gravity near black holes influences the polarization signals from orbiting accretion disc clumps, highlighting relativistic effects on observed polarization variability.

Contribution

It introduces a model analyzing polarization changes caused by relativistic effects on inhomogeneous, orbiting accretion disc clumps near black holes.

Findings

Relativistic effects significantly modulate polarization signals.

Polarization variability correlates with orbital motion and gravity effects.

Model predicts rapid polarization changes observable in light curves.

Abstract

Accretion onto black holes often proceeds via an accretion disc or a temporary disc-like pattern. Variability features, observed in the light curves of such objects, and theoretical models of accretion flows suggest that accretion discs are inhomogeneous and non-axisymmetric. Fast orbital motion of the individual clumps can modulate the observed signal. If the emission from these clumps is partially polarized, which is likely the case, then rapid polarization changes of the observed signal are expected as a result of general relativity effects.