The effects of thermal conduction on the ADAF with a toroidal magnetic field

Abstract

The observation of the hot gas surrounding Sgr $A^*$ and a few other nearby galactic nuclei imply that electron and proton mean free paths are comparable to the gas capture radius. So, the hot accretion flows is likely to proceed under week-collision conditions. Hence, thermal conduction has been suggested as a possible mechanism by which the sufficient extra heating is provided in hot ADAF accretion disks. We consider the effects of thermal conduction in the presence of a toroidal magnetic field in an advection-dominated accretion flow around a compact object. For a steady-state structure of such accretion flows a set of self-similar solutions are presented. We find two types solutions which represent high and slow accretion rate. They have different behaviors with saturated thermal conduction parameter, $\phi$.