Velocity shear stabilization of interchange modes in elongated plasma configurations

Abstract

Interchange modes in magnetized plasmas can be stabilized by cross-field velocity shear. This effect is re-examined for systems with elongated cross-sections. For large elongations, E, the interchange growth drops as E−1/2 while the velocity shear scale is still determined by the short scale size. Consequently, velocity shear stabilization of elongated plasmas is shown to be more efficient by E−1/2.