The impact of Faraday effects on polarized black hole images of Sagittarius A*

Understand

We study model images and polarization maps of Sagittarius A* at 230 GHz.

• We post-process GRMHD simulations and perform a fully relativistic radiative transfer calculation of the emitted synchrotron radiation to obtain polarized images for a range of mass accretion rates and electron temperatures.
• At low accretion rates, the polarization map traces the underlying toroidal magnetic field geometry.
• At high accretion rates, we find that Faraday rotation internal to the emission region can depolarize and scramble the map.