General Physics Physics Seminar 26 February 2004


Physics of Accretion and Ejection of matter flow around Black holes

Indranil Chattopadhyay

Centre for Plasma Astrophysics, Department of Mathematics
K. U. Leuven, Leuven, Belgium


Black holes (BH) are black, and one of the ways to see them, is to study the `funny' behaviour of matter accreting onto it. Matter accreting onto BHs undergoes centrifugal pressure mediated shocks in much of the parameter space. These shock solutions naturally explain the two `spectral' states of BH candidates, namely the `hard' and the `soft' states. This model also generates the `weak' power law part of spectrum in soft states, which is perhaps the only explanation for the existance of the `horizon'.

The unbalanced thermal gradient force along z-axis in the post-shock disc in the hard state, drives a part of the infalling matter in the form of jets. We also show that, the photons coming out of the disc in hard states can accelerate these jets to highly relativistic jets.