Deceleration of the disk by the accreting magnetized star in the corotation approximation

Abstract

We analyze the process of interaction of the viscous keplerian accretion disk with the dipole magnetic field of the accretor within the corotation approximation. We estimate the radial dependence of the gaseous pressure in such non-magnetized accretion disk. We calculate the equilibrium radius at which the gaseous pressure in the disk is balanced by the pressure of the dipole magnetic field of the accreting star. We show that this radius depends on the disk viscosity and is significantly smaller than the canonical Alfvén radius realized in the process of spherical accretion.