Poster details
» Hot-spot model for accretion disc variability as random process
Presenter: Tomáš Pecháček
Radiation from accreting black holes varies on different time-scales. In X-rays, the observed light-curve, is a complicated noisy curve that can be represented by a broad-band power spectrum. The `hot spots' on the accretion disc have been identified a possible contributor to this variability. These spots are supposed to occur on the surface of an accretion disc following its irradiation by coronal flares. Various schemes have been proposed in which spots are mutually interconnected in some way. We discuss the statistical properties of model light-curves, constructed as a sum of contributions from many point-like sources that are orbiting above an underlying accretion disc. Particularly, we examine the power spectral profiles generated by different kinds of avalanching mechanisms, using the framework of the theory of point processes.
Authors:- T. Pecháček
- V. Karas
- B. Czerny