An accretion disc instability induced by a temperature sensitive α parameter

  title={An accretion disc instability induced by a temperature sensitive $\alpha$ parameter},
  author={William J Potter and Steven A. Balbus},
  journal={Monthly Notices of the Royal Astronomical Society},
  • W. Potter, S. Balbus
  • Published 31 March 2014
  • Physics
  • Monthly Notices of the Royal Astronomical Society
In the standard thin disc formalism the dimensionless $\alpha$ parameter is usually assumed to be constant. However, there are good theoretical reasons for believing, as well as evidence from simulations, that $\alpha$ is dependent on intrinsic disc properties. In this paper we analyse the conditions for the stability of a thin accretion disc in which $\alpha$ is a function of the magnetic Prandtl number, the ratio of collisional viscosity to resistivity. In the inner disc, where the free… 

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