HR: 1330h
AN: SP43B-02 [Abstracts]
TI: 3D MHD Shear instabilities in the Solar Tachocline
AU: * Miesch, M
EM: miesch@ucar.edu
AF: HAO/NCAR, 3450 Mitchell Lane, Boulder, CO 80027 United States
AB:
In the past decade, linear analysis has shown that the latitudinal differential rotation in the solar tachocline is unstable
in the presence of a toroidal field under a wide range of field amplitudes and configurations. The most unstable modes are
generally tipping modes whereby a band of toroidal field evolves such that its central axis tips away from the rotation axis. Previous studies of these instabilities have been based on two-dimensional (latitude-longitude) models or on the MHD
shallow-water approximation in which horizontal velocities and fields are still independent of height but are no longer
required to be divergenceless. Recently we have extended these linear analyses to 3D using a thin-shell model. Here we
present nonlinear simulations of these 3D MHD shear instabilities.
DE: 7524 Magnetic fields
DE: 7544 Stellar interiors and dynamo theory
SC: Solar Physics Division - AAS [SP]
MN: 2005 Joint Assembly