Beam-plasma interaction during electron beam injection into a symmetrically open plasma system

Amplitude-frequency spectra and localization of oscillations excited when the electron beam (Eb=0.5-2.0 keV) is injected through the symmetrically open plasma system with the independent hot cathode Penning dischargeare experimentally investigated. When crossing in consecutive order the plasma regions with different correlation of the electron plasma frequency and electron cyclotron frequency the electron beam is shown to excite in the system the whole complex of oscillations with different dispersions, thus creating favourable conditions for its consecutive relaxation. The conditions for excitation of the oscillations and the factors determined their localization are discussed