Excitation of Electromagnetic Waves from a Rotating Annular Relativistic E-Beam.

摘要

Propagation of a thin rotating relativistic electron beam through a circular waveguide is shown to excite both the transverse electric and transverse magnetic modes of the guide. The beam is guided by and rotates symmetrically about a constant uniform external magnetic field. Both the synchronous and cyclotron modes associated with the beam can interact with either waveguide mode to excite electromagnetic radiation. The dispersion relations for the four coupling processes are derived and analyzed. Finally, application of this mechanism to the generation of intense microwave radiation is discussed in the light of recent experiments.