Design studies of a RF interaction cavity for a 4 MW, 170 GHz triangular corrugated coaxial cavity gyrotron

Abstract

Gyrotrons are very powerful coherent sources of radiation. In coaxial cavity gyrotron, an insert is present in the cavity which leads to reduction in the voltage depression and change the eigenvalue, depending on the radii ratio. As a result a coaxial cavity can be fine- tuned for very higher power at very higher frequencies in comparison to cylindrical cavity. In this paper design studies of a coaxial cavity for 170 GHz, 4 MW gyrotron are given. The insert is corrugated with triangular corrugations. The advantage of such a corrugation type is that it allows more number of slots to be included on the insert, without causing the problem of localized heating. Single mode self consistent calculation is carried out for the calculation of output power and efficiency. Wall losses and diffractive quality factors for desired and competing modes have been calculated.