Are Particles in Advection‐dominated Accretion Flows Thermal?
Are Particles in Advection‐dominated Accretion Flows Thermal?
We investigate the form of the momentum distribution function for protons and electrons in an advection-dominated accretion flow (ADAF). We show that for all accretion rates, Coulomb collisions are too inefficient to thermalize the protons. The proton distribution function is therefore determined by the viscous heating mechanism, which is unknown. …