Ballooning Instabilities in Hot Electron Plasmas

The stability of short‐wavelength, low‐frequency modes in a hot electron plasma is investigated. Particular attention is devoted to the effect of the dependence of perturbed quantities along the equilibrium magnetic field lines. Two types of modes in a bumpy torus are considered: modes which are nearly flutes in each mirror cell but vary in phase from cell to cell, and modes which have significant variation in each cell. Generally speaking, allowing perturbations to vary along the field lines is destabilizing. However, sufficiently large hot electron gyroradii can stabilize all short perpendicular wavelength modes.