Plasma-filled gyrotron employing a relativistic supervacuum electron beam

Results are reported for an experimental study of a gyrotron that employs a relativistic supervacuum electron beam with an electron energy of 320 keV, a current of 1.2 kA, and a pulse length of 30 nsec. The space charge of the electron beam was compensated by filling the gyrotron with a previously prepared xenon plasma. In the experiments, microwave emission in the expected TE(13) mode was obtained at a wavelength of 3 + or - 0.1 cm with a maximum output power of 60 MW and a conversion efficiency of approximately 15%. The dependence of output power on plasma density is examined.