DYNAMICAL EVOLUTION OF SPECTRAL AND TIMING PROPERTIES OF COMPACT OBJECTS: SOME EXAMPLES

Abstract

We present examples of rapid changes in spectral and timing properties in accretion flows around compact objects and discuss what could be going on in these systems. We find a new way of quantifying the variation of the flow geometry. We show the evolution of the variation of the Comptonization efficiency computed from the ratio of the Comptonized photons and the injected seed photons. The time evolution is a direct consequence of the variation of the accretion rates which changes the hydrodynamic and radiative properties of the flow and therefore the flow geometry.