Possibilities of Creating a Relativistic Terahertz Gyrotron with a Multi-megawatt Power Level

Calculations of a three-electrode magnetron-injection gun with a thermionic cathode for a relativistic gyrotron in the 300 GHz range have been performed. The possibility of forming a helical electron beam with an energy of 250 keV, a current of 100–300 A and a pitch factor of 1.1 has been demonstrated. Calculations of electron-wave interaction were performed for various versions of the gyrotron cavity. Both the classic version of a regular cylindrical cavity and a promising version of a longitudinal slot-type cavity are considered. The possibility of generating radiation in the range of 0.3 THz with a power of more than 7 MW has been demonstrated.