Stability of MRI Turbulent Accretion Disks

Details Stability of MRI Turbulent Accretion Disks Stability of MRI Turbulent Accretion Disks

Dec 2010

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2010fym..confp...9t&link_type=abstract

"The First Year of MAXI: Monitoring Variable X-ray Sources", Poster Presentations, 4th International MAXI Workshop held November

Physics

Scientific paper

We study the stability of geometrically thin accretion disks with non-standard α parameter, which characterizes the efficiency of the angular momentum transport. Following recent results of numerical simulations of the Magnetorotational instability (MRI) driven turbulence, we assume that α increases with the magnetic Prandtl number. By adopting Spitzer's microscopic diffusivities, we obtain local structures of geometrically thin accretion disks consistently including effects of MRI-driven turbulence. Since the magnetic Prandtl number increases with the temperature, the efficiency of the angular momentum transport and thus viscous heating rate are smaller for a larger radius when δ > 0. We find that such disks can be unstable to gravitational, thermal, and secular instabilities. It is most remarkable feature that the thermal and secular instabilities can grow in the middle part of accretion disks even when the radiation pressure is negligible, while the standard Shakura & Sunyaev's accretion disk (constant α) is stable to these instabilities. We conclude that it would be difficult to maintain the steady mass accretion state unless the Pm-dependence of the MRI-driven turbulence is weak. Consideration of Pm dependence of α due to the MRI-driven turbulence may make the phase transition of accretion disks less mysterious.

Affiliated with

Also associated with

No associations

Rating

Stability of MRI Turbulent Accretion Disks does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Stability of MRI Turbulent Accretion Disks, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Stability of MRI Turbulent Accretion Disks will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1290385