Volume 96, Number 1, October 2011
|Number of page(s)||6|
|Section||Geophysics, Astronomy and Astrophysics|
|Published online||16 September 2011|
Ring sequence decomposition of an accretion disk: The viscoresistive approach
Department of Physics, “Sapienza” Università di Roma - Piazzale A. Moro, 5, 00185, Rome, Italy, EU
2 ENEA, C.R. Frascati (Department UTFUS-MAG) - Via Enrico Fermi, 45, 00044, Frascati (Rome), Italy, EU
3 Istituto Nazionale di Fisica Nucleare (INFN), Sezione di Roma 1 - Rome, Italy, EU
Accepted: 12 August 2011
We analyze a two-dimensional viscoresistive magnetohydrodynamical (MHD) model for a thin accretion disk which reconciles the crystalline structure outlined in Coppi B., Phys. Plasmas, 12 (2005) 7302 and Coppi B. et al., Astrophys. J., 641 (2006) 458, with real microscopic and macroscopic features of astrophysical accreting systems. In particular, we consider small dissipative effects (viscosity and resistivity, characterized by a magnetic Prandtl number of order unity), poloidal matter fluxes and a toroidal component of the magnetic field. These new ingredients allow us to set up the full equilibrium profile including the azimuthal component of the momentum conservation equation and the electron force balance relation. These two additional equations, which were identically satisfied in the original model, permit us to deal with non-zero radial and vertical matter fluxes, and the solution we construct for the global equilibrium system provides a full description of the radial and vertical dependence within the plasma disk. The main issue of our analysis is outlining a modulation of the matter distribution in the disk which corresponds to the formation of a ring-like sequence, here associated with a corresponding radial oscillation of the matter flux.
PACS: 97.10.Gz – Accretion and accretion disks / 95.30.Qd – Magnetohydrodynamics and plasmas / 52.30.Cv – Magnetohydrodynamics (including electron magnetohydrodynamics)
© EPLA, 2011
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.