Optimization of a Compact Gyrotron with an Axis-Encircling Beam for Spectroscopic Applications

A new version of a compact gyrotron with an axis-encircling beam is discussed. This gyrotron has an azimuthally asymmetric electron gun, which forms an axis-encircling helical electron beam (HEB). Non-adiabatic effects are not used to form a HEB in a compact gyrotron in contrast to a conventional gyrotron with an axis-encircling beam. However, there is no azimuthal symmetry of the system electrodes. The power of the formed HEB is relatively low, but sufficient for spectroscopic applications. This gyrotron modification can be used with “budget” cryogen free magnet with a small bore. An example of a compact gyrotron with a radiation frequency of 395 GHz is presented.