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Secular instability in quasi-viscous disc accretion

Jayanta K. Bhattacharjee·Arnab K. Ray
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Abstract

A first-order correction in the $α$-viscosity parameter of Shakura and Sunyaev has been introduced in the standard inviscid and thin accretion disc. A linearised time-dependent perturbative study of the stationary solutions of this "quasi-viscous" disc leads to the development of a secular instability on large spatial scales. This qualitative feature is equally manifest for two different types of perturbative treatment -- a standing wave on subsonic scales, as well as a radially propagating wave. Stability of the flow is restored when viscosity disappears.

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Jayanta K. Bhattacharjee, Arnab K. Ray. 2007-11-07. Secular instability in quasi-viscous disc accretion. https://doi.org/10.1086/521042

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