Stability of Accretion Disc around a Black Hole: effects of Bremsstrahlung and Synchrotron Cooling

Abstract

We perform stability analysis of an accretion disc around a stellar mass black hole. The cooling of the accretion flow due to bremsstrahlung and synchrotron radiation processes are considered. The solutions with shock are perturbed at the shock location and the radial dependence of perturbation is obtained by solving the equations numerically using fourth-order Runge-Kutta method. The perturbations are assumed to be infinitesimal, thereby allowing a linear analysis. The frequencies that solve the equations are found and the existence of unstable frequencies implies instability.