A note on magnetized coronae

TL;DR

This paper explores how strong vertical magnetic fields influence the structure and heating of coronae in AGN and X-ray binaries, proposing magnetic pumping as a key energy transfer mechanism.

Contribution

It introduces the concept that magnetic pumping can extract energy from accretion disks to heat magnetized coronae, challenging existing models.

Findings

Magnetic fields significantly affect corona structure and heating.

Magnetic pumping can transfer energy from disks to coronae.

Reconsideration of corona models is necessary with strong magnetic fields.

Abstract

X-ray binaries and AGN show observational evidence for magnetized hot plasmas. Despite years of data, very little is known on these {\it coronae} especially on the mechanisms responsible for their heating, and most models simply assume their existence. However, understanding its properties has now become a key issue of the AGN and microquasars modelling. Here we consider the effect of a strong vertical magnetic field on the corona AGN and X-ray binaries and show that its modeling (structure, heating) must be reconsidered. As a first step, we present one mechanism that could extract energy from the accretion disks and deposits it in the coronae: the {\it magnetic pumping