New Trapped-Electron Instability

We have found a new instability that is driven by a radial gradient of the electron temperature or by the electron drift in the "unfavorable" curvature of the magnetic field lines for high-temperature confined plasmas in which a fraction of the electron population is magnetically trapped. The relevant mode is standing along the magnetic field, is symmetric about the point of minimum field, and has relatively short wavelengths across the magnetic field.