Effects of anisotropic thermal conduction on wind properties in hot accretion flow

TL;DR

This study investigates how anisotropic thermal conduction influences wind properties in hot accretion flows around black holes, revealing significant effects on wind energy flux and velocity through two-dimensional MHD simulations.

Contribution

It is the first to analyze the impact of anisotropic thermal conduction on wind production in hot accretion flows using detailed simulations.

Findings

Wind energy flux increases by a factor of ~10 with thermal conduction.

Wind velocity increases due to enhanced driving forces.

Thermal conduction moderately affects wind mass flux.

Abstract

Previous works have clearly shown the existence of winds from black hole hot accretion flow and investigated their detailed properties. In extremely low accretion rate systems, the collisional mean-free path of electrons is large compared with the length-scale of the system, thus thermal conduction is dynamically important. When the magnetic field is present, the thermal conduction is anisotropic and energy transport is along magnetic field lines. In this paper, we study the effects of anisotropic thermal conduction on the wind production in hot accretion flows by performing two-dimensional magnetohydrodynamic simulations. We find that thermal conduction has only moderate effects on the mass flux of wind. But the energy flux of wind can be increased by a factor of $\sim 10$ due to the increase of wind velocity when thermal conduction is included. The increase of wind velocity is because of the increase of driving forces (e.g. gas pressure gradient force and centrifugal force) when thermal conduction is included. This result demonstrates that thermal conduction plays an important role in determining the properties of wind.