A MULTI-MEGAWATT MILLIMETER-WAVE SOURCE FOR PLASMA HEATING AND CONTROL

THIS PROJECT IS INVESTIGATING THE FEASIBILITY OF GYROHARMONIC CONVERSION USING A SPATIOTEMPORALLY MODULATED ELECTRON BEAM FOR EFFICIENT GENERATION OF MULTI-MEGAWATT MILLIMETER WAVELENGTH RADIATION FOR ELECTRON CYCLOTRON RESONANCE HEATING (ECRH) PLASMA HEATING AND CONTROL. FEASIBILITY HINGES ON DEMONSTRATION OF REASONABLE HIGH HARMONIC CONVERSION EFFICIENCY AND SUPPRESSION OF COMPETING MODES. PREVIOUS THEORETICAL WORK HAS SHOWN HIGH EFFICIENT FIFTH HARMONIC CONVERSION AT 94 GHZ, PRODUCING MEGAWATT-LEVEL POWER. THE NONLINEAR ANALYSIS AND PARTICLE SIMULATIONS WILL EXTENDED TO 13TH AND HIGHER HARMONICS DURING PHASE I TO OBTAIN THE DESIGN PARAMETERS OF A HARMONIC CONVERTER FOR THE PRODUCTION OF POWER AT 140 GHZ AND ABOVE USING AN X-BAND (8 TO 12 GHZ) RF DRIVER. METHODS TO INHIBIT POWER FLOW TO COMPETING CONVERTER MODES WILL BE EXPLORED. SUCCESSFUL RESULTS OF THE PHASE I STUDY ARE EXPECTED TO LEAD TO DESIGNS FOR PROOF-OF-PRINCIPLE EXPERIMENTS TO BE CARRIED OUT DURING PHASE II.