ELECTRON-CYCLOTRON-RESONANCE HEATING NEAR THE TURNING-POINT IN INHOMOGENEOUS MAGNETIC-FIELD

Cyclotron resonance heating of electrons in a magnetic beach is studie d by rigorous numerical analysis of the electron trajectories. It is c onfirmed that a heating response function [Y. Kiwamoto et al., Phys. P lasmas 1 834 (1994)] connecting the velocity distributions in both sid es of the resonance layer can be applied over a wider range of electro n velocities than originally expected. For electrons mirror-reflected close to the resonance layer, however, the electron velocity distribut ion after heating substantially deviates from the prediction of the re sponse function. The deviation is quantitatively evaluated to obtain a criterion of applicability of the response function. (C) 1996 America n Institute of Physics.