Design And Optimization Of A High-Power S-Band Klystron

Abstract

With the increasing energy demands of facilities such as the Circular Electron Positron Collider (CEPC) and the Hefei Advanced Light Facility (HALF), existing S-band klystrons face challenges in meeting performance requirements. This necessitates the development of high-power, high-efficiency S-band klystrons. This paper presents the design process and parameter optimization of an 80 MW S-band high-power compact klystron, focusing on the electron gun, focusing magnetic field, and cavities. To ensure accuracy, simulations were conducted using 1D, 2D, 2.5D, and 3D codes, cross-validated for consistency. The simulation results demonstrate that the klystron design is optimized in terms of beam dynamics, frequency sensitivity, and power transfer curves, meeting the design specifications. CST 3D particle-in-cell (PIC) simulations achieved an output power of 84 MW with a saturation efficiency of 47.2%.

Keywords: klystron, electron gun, focusing magnetic field, cavity