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arXiv · 0905.3656

On the Maximal Value of the Turbulent alpha-Parameter in Accretion Discs

P. Abolmasov·N. I. Shakura
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Abstract

In this short paper we show that making turbulence two- rather than three-dimensional may increase effective turbulent viscosity by about 40%. Dimensionless hydrodynamical viscosity parameter up to \alpha\_{max} = 0.25 M_t^2 may be obtained in this approach, that is in better agreement with the observational data on non-stationary accretion than the values obtained in numerical simulations. However, the \alpha-parameter values known from observations are still several times higher.

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P. Abolmasov, N. I. Shakura. 2009-05-22. On the Maximal Value of the Turbulent alpha-Parameter in Accretion Discs. https://doi.org/10.1002/asna.200911230

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