A Study of the Influence of the Beam and Field Parameters on the Terahertz Multiwave Cherenkov Generator Efficiency

The interaction of a relativistic electron beam with an energy of 280–1500 keV and electromagnetic resonances in a multiwave Cherenkov generator with a diffraction reflector is studied using a 2.5D hybrid code. The main calculations are performed with a 5 kA tubular beam current injected into an electrodynamic system with a diameter of 40 mm. The frequencies are varied within 358–368 GHz. The parameter regions of stable radiation generation during synchronization of electromagnetic resonances by an electron beam and the power self-modulation mode are found. The total radiation power in the calculations, excluding ohmic losses, reaches 2.32 GW with a generation efficiency of 42%. The radiation power decreases by two orders of magnitude with an increase in the electron energy from 1100 keV to 1150 keV. The optimal beam and electrodynamic system parameters in the electron energy range up to 500 keV are found.