New solution to viscous evolution of accretion disks in binary systems
Abstract
Analytical investigation of time-dependent accretion in disks is carried out. We consider a time-dependent disk in a binary system at outburst which has a fixed tidally-truncated outer radius. The standard Shakura-Sunyaev model of the disk is considered. The vertical structure of the disk is accurately described in two regimes of opacity: Thomson and free-free. Fully analytical solutions are obtained, characterized by power-law variations of accretion rate with time. The solutions supply asymptotic description of disk evolution in flaring sources in the periods after outbursts while the disk is fully ionized. The X-ray flux of multicolor (black-body) alpha-disk is obtained as varying quasi-exponentially. Application to X-ray novae is briefly discussed concerning the observed faster-than-power decays of X-ray light curves. The case of time-dependent advective disk when the exponential variations of accretion rate can occur is discussed.
Cite
@article{arxiv.astro-ph/0103274,
title = {New solution to viscous evolution of accretion disks in binary systems},
author = {G. V. Lipunova and N. I. Shakura},
journal= {arXiv preprint arXiv:astro-ph/0103274},
year = {2011}
}
Comments
14 pages, 3 figures, typos are corrected in formulae (17),(26),(29),(31),(34),(46)