Experimental Studies On Two Types Of Magnetic Potential Wells

Abstract

In several gyrotron prototype tubes, harmful voltage stand-off instabilities were observed during the test campaign period1. It has been shown that the formation of magnetic potential wells in the design of the gyrotron magnetron injection gun (MIG) can initiate such instabilities2. However, it is still not clear which type of the potential wells create these problems and the detailed mechanism to explain that behavior is not known. In the context of this work, two different types of potential wells are theoretically and experimentally investigated. Numerical studies have been performed using the Ariadne code3, while a mock-up device has been designed and manufactured for the experimental investigation of both types of magnetic potential wells in several regimes of operating parameters. The deeper understanding of the magnetic potential well trap behavior is very important for the future design of simpler and robust gyrotron MIGs.