Optimization Design of the Magnetron Injection Gun for the Gyrotron with a Pulsed Magnet

The magnetron injection gun (MIG) of the gyrotron is a complex particle dynamics system. It is a tedious and difficult task to design the MIG, especially under a pulsed high magnetic field. In this paper, the design process of the MIG for the gyrotron with a pulsed magnet is proposed based on the idea of optimization. The pulsed magnet is optimized by considering the efficient factor, field homogeneity, electrical parameters, thermal and mechanical strength. With the obtained magnetic field distribution, the electrode of the MIG is automatically designed by using constrained multiobjective optimization. Based on this process, a case study of the MIG with a 15 T pulsed magnet for a 400 GHz gyrotron is given.