Generation of large-orbit electron beam using magnetron type injection gun

Abstract

The generation of axis-encircling large-orbit electron beam using magnetron type injection gun is studied theoretically and numerically. Since the cathode emission band is parallel not only to the system’s axis but also to the magnetic field lines, it eliminates the initial angular momentum spread at the cathode and helps to reduce the velocity spread greatly. Through numerical simulation by EGUN, a large-orbit electron beam with axial velocity spread of 1.82%, guiding center deviation of 6.1%, and velocity ratio of 1.67 is obtained. By adjusting the voltages of the two anodes, the beam quality can be modulated easily to meet the specific requirements of different gyro-devices. The scheme provides a new electron gun candidate for the large-orbit devices.

Acknowledgement

This work is supported by the National Natural Science Foundation of China (Grant No. 60971035).