Global Structures of Advection-Dominated Two-Temperature Accretion Disks

Models of steady transonic global flows of optically thin, advection-dominated, two-temperature accretion onto black holes have been constructed. The physical quantities integrated over the vertical direction are treated with the Shakura-Sunyaev type α-viscosity. Bremsstrahlung and Compton cooling are considered, but synchrotron-Compton cooling is not taken into account. It has been found that the electron temperature in the inner part of the disk is fairly high in our model, because the surface density is low and the cooling there is rather inefficient. We have obtained Ṁcrit above which no steady solution is allowed, and have found that it is necessary to consider the relativistic cooling effect in the state that the electron temperature is higher.