The dependence of general relativistic accretion on black hole spin

We propose a novel approach to the investigation of how black hole spin influences the behavior of astrophysical accretion. We examine the terminal behavior of general relativistic, multitransonic, hydrodynamic advective accretion in the Kerr metric, by analyzing various dynamical as well as thermodynamic properties of accreting matter extremely close to the event horizon, as a function of Kerr parameter a. The examination of the transonic properties of such flows can be useful in self-consistently discriminating between prograde and retrograde relativistic accretion and in studying the spectral signatures of black hole rotation.