High-Energy Electron Production by Vp × B Acceleration in Microwave-Plasma Interaction Experiments

Detailed experimental observations on the microwave plasma interaction in a nonuniform plasma with weak magnetic field (Ω/ω ≦ 10-2) have revealed that high-energy electrons are produced by a process of the VP × B acceleration, where Ω and ω are, respectively, electron cyclotron and microwave frequencies. The maximum energy of hot electrons increases almost linearly to about 1 keV with the RF power up to 8 kW. Hot electrons are produced from typically two regions; one in the underdense region (several centimeters down the critical layer for the resonance absorption) and the other in the resonance absorption area. The theoretical predictions have interpreted the experimental results in reasonable agreement.