Shock Formation in Adiabatic Accretion Flows around a Kerr Black Hole

Abstract

Shock formation in adiabatic accretion flows around a Kerr black hole is analytically proved for two cases, i.e. Rankine-Hugoniot shocks and isothermal shocks. In the former case it is shown that for given flow parameters (the specific total energy and the specific angular momentum) there can be no more than one stable standing shock, and the global flow solution can only be of α-x type. However, the solution topology in the latter case shows new remarkable characteristics: for given flow parameters there can be two stable standing shocks, and the global solution can be of three types, namely α-x, x-α, and α-α type. It is also significant that the effects of frame-dragging of Kerr geometry on the shock formation are found out. Finally, some comments are made on the reason why numerous authors who have studied advection dominated accretion flows have found no shocks, and on the observational significance of the shock study.KeywordsBlack HoleGlobal SolutionKerr Black HoleShock LocationSonic PointThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.