Numerical study of drift-Alfvén waves in a sheared magnetic field

Abstract

The coupled radial eigenmode equations for electromagnetic drift waves in a sheared magnetic field are solved numerically. In addition to the familiar drift eigenmodes, a different set of eigenmodes was found which is the analog of the sheared Alfvén waves of local theory in a sheared magnetic field. The drift mode is mainly electrostatic, and the shear Alfvén mode is mainly electromagnetic and closely related to the high-order tearing modes.