Stimulated Cherenkov effect and dissipative-radiative instabilities in superluminal motion of a relativistic electron beam in a layered medium

Dissipative–radiative instabilities and instabilities caused by the stimulated Cherenkov effect of a relativistic electron beam in an unbounded layered electrodynamic system are considered. While for the stimulated Cherenkov effect the beam energy is used to excite waves in the electrodynamic system, for dissipative–radiative instabilities, the beam energy is radiated away from the system to infinity. Such irreversible energy transfer from the beam manifests itself as a kind of effective dissipation and makes the dissipative–radiative instability an analogue of the usual dissipative beam instability in a system without radiation. Growth rates and frequency ranges of the instabilities are found for various structures of layered electrodynamic systems, including plasma systems.