LAUSR

The feasibility of a high-power sub-THz gyrotron with smooth wideband frequency tuning suitable for direct measurement of the positronium hyperfine structure is demonstrated numerically using both averaged equations and PIC-code simulations. Analytical estimates show that the frequency-tunable powerful sub-THz radiation can be generated through the excitation of high-order axial modes in a gyrotron with short cavity driven by an electron beam with high current. Simulations show that an output power of 0.5–1 kW can be obtained at a frequency of about 0.2 THz within a 10-GHz band which are the parameters needed for testing of quantum electrodynamics predictions through the spectroscopy of positronium.