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Magnetically Heated Accretion Disk Coronae
Expect strong B:
Keplerian Shear+convectionBouyancy Loops
Observe:
Power law flickeringEmission Lines (Horne & Saar)Jets
Ueno et al.
Early Scenario
Galeev, Rosner & Vaiana
Black Hold Disk: Cygnus X-1
Scaling like solar coronal loops
Thermal Conduction + Radiation or Compton Cooling
B in equipartion within disk
T ~ 5x108 , ne ~ 10 19
Magnetorotational Instability
Balbus & Hawley
Viscosity >> MolecularConvection doesn’t work
Miller & Stone
Poynting flux ~ 25% Ediss
Sheets?
Low β Corona
Nanoflares? Pavlidou et al.
Cellular automaton model
Naturally gives power law
Angular momentum transfer byReconnection in corona alone
CMEs?? Strong winds sometimes
Can collimate flow (Williams)
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