MHD turbulence in accretion disks is thought to cause outward angular momentum transport and cascading of energy to smaller scales where the energy is dissipated. We have computed the dispersion relation for MHD waves including the effects of radiation, and we conclude that if radiation pressure is larger than any other pressure in the disk, then photon diffusion can damp compressive waves, causing dissipation of the turbulence and heating of the disk. This mechanism depends on coupling incompressive and compressive turbulence, and radiation pressure domination which occurs in optical thick, geometrically thin disks with large (near-Eddington) accretion rates onto compact objects.
American Astronomical Society Meeting Abstracts #192
- Pub Date:
- September 1998