Interaction of the accretion disk with the rotating stellar magnetic field: plasma diffusion and angular momentum transfer across the Alfvén surface.
Abstract
By starting with a general consideration for the force-balance condition between the accretion disk and the rotating stellar magnetic field, the plasma diffusion and angular momentum transfer across the Alfven surface is investigated. The accreting plasma penetrates into the boundary layer through the diffusion process caused by the anomalous electric resistivity, which in turn results from the magnetic-field fluctuations created in the accretion disk. A formalism is provided by which the position of the Alfven surface and the thickness of the boundary layer are explicitly determined. Those calculations are applied to the accretion model of the X-ray pulsars, and the theoretical results on the spin-up rate are compared with the observational data. In addition to reproducing the well-known agreement on the slow pulsars, the results indicate a way in which the spin-up characteristics of Her X-1 may be quantitatively explained.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- August 1978
- DOI:
- 10.1086/156366
- Bibcode:
- 1978ApJ...224..198I
- Keywords:
-
- Magnetohydrodynamics;
- Plasma Diffusion;
- Stellar Magnetic Fields;
- Stellar Mass Accretion;
- Stellar Rotation;
- Angular Momentum;
- Binary Stars;
- Boundary Layers;
- Electrical Resistivity;
- Neutron Stars;
- Pulsars;
- X Ray Astronomy;
- Astrophysics;
- Accretion:X-Ray Pulsars;
- Accretion Disks:Stellar Magnetic Fields