Resonant Cherenkov emission of whistlers by a modulated electron beam

Emission of whistler waves through the Cherenkov resonance mechanism has be en studied in a laboratory experiment modeling the interaction of a modulat ed electron beam with a magnetized plasma under conditions relevant to spac e experiments involving electron beam injection. The characteristics of the emission and the propagation of the radiated whistlers, and namely the fea tures of their directive radiation patterns, have been controlled as a func tion of the beam and plasma parameters. This beam radiation process can be distinguished from another mechanism of wave emission, the nonresonant tran sition radiation from the beam injection point, owing to adequate choices o f the physical conditions. (C) 1999 American Institute of Physics. [S1070-6 64X(99)00607-2].