FREE ELECTRON SOURCES OF HIGH FREQUENCY RADIATION (LASER-STIMULATED, RAMAN SCATTERING, CYCLOTRON MASER)

The stimulated Raman scattering free electron laser, the elec- tron cyclotron maser and an aspect of the transmission system are analyzed with aims to optimize their performance in the microwave to ultraviolet. This thesis has four major parts.;The pump depletion nonlinearity and the parametric approxi- mation are exploited for stimulated Raman scattering from an unbounded and a bounded (parallel-plate waveguide) relativistic electron beam. Exact analytical expressions for the saturation periods are derived. Mismatch, wall and/or dissipative losses are accounted for. In the unbounded case, increases in the uniform focusing field (B(,0)) enhances the growth rate and reduces the saturation power and time and amplitude threshold. Different sets of parameters lead to enhanced saturation powers and times when B(,0) is increased. The instability is purely convective. A fully focused beam was assumed in the bounded case. The saturation period for this was over two magnitudes greater than that in the unbounded B = 0 case. Varying the plate separation optimizes the parametric traits. A cylindrical waveguide mode converter with radius periodi- cally perturbed in axial direction is optimized. Correcting the corru- gation period or design frequency, efficiency enhancement of 32% is observed. Coupling coefficients for forward propagating modes are expressed analytically.;A kinetic treatment of the electron cyclotron maser interaction between a tenuous annular relativistic electron beam and the TE(,0L) mode in a cylindrical waveguide is presented. Including all guiding center trajectory function effects, an improved dispersion relation is obtained. Adding the TM(,0n) mode, the derived dispersion relation, valid at all harmonic cyclotron frequencies, exhibits coupling between the two waveguide modes. The electron cyclotron maser gyrotron is analyzed with respect to coupling performance.;A unified set of energy, linear and angular momentum transport equations are derived for a dispersive medium capable of supporting weakly decaying or growing waves. Reactive sources are shown to alter the commonly used definition of group velocity.