منابع مشابه
Ab initio Simulations of Accretion Disc Boundary Layers
I discuss the results of simplified three dimensional magnetohydrodynamic simulations of the boundary layer between a disc and a non-rotating, unmagnetized star. Strong magnetic fields, possibly approaching equipartition with the thermal energy, occur in the boundary layer due to the shearing of disc-generated fields. The mean boundary layer magnetic field, which is highly variable on an orbita...
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We use three dimensional magnetohydrodynamic simulations to study the structure of the boundary layer between an accretion disc and a non-rotating, unmagnetized star. Under the assumption that cooling is efficient, we obtain a narrow but highly variable transition region in which the radial velocity is only a small fraction of the sound speed. A large fraction of the energy dissipation occurs i...
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A first-order correction in the α-viscosity parameter of Shakura & 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 p...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2013
ISSN: 0035-8711,1365-2966
DOI: 10.1093/mnras/stt182