Steady state whistler turbulence and stability of thermal barriers in tandem mirrors

Abstract

The effect of the whistler turbulence on anisotropic electrons in a thermal barrier is examined. The electron distribution function is derived self-consistently by solving the steady state quasilinear diffusion equation. Saturated amplitudes are computed using the resonance broadening theory or convective stabilization. Estimated power levels necessary for sustaining the steady state of a strongly anisotropic electron population are found to exceed by orders of magnitude the estimates based on Fokker–Planck calculations for the range of parameters of tandem mirror (TMX-U and MFTF-B) experiments [Nucl. Fusion 25, 1205 (1985)]. Upper limits on the allowed degree of anisotropy for existing power densities are calculated.