Design Study of Electron Gun for CEPC 650 MHz Klystron

This paper presents the design and simulation of an electron gun for 800 kW CW klystron of which frequency is 650 MHz for CEPC project. An electron gun with a modulating anode is designed using DGUN software. The uniform beam trajectories, with a beam perveance of 0.64μA/V 3/2 are simulated. We employed a Ba-dispenser cathode of radius 35 mm with Φ10 hole at the center and obtained a current density on cathode less than 0.45 A/cm². The beam trajectories were also simulated over whole tube length with a magnetic field of 207 Gauss. Expecting functions using the modulating anode gun are also described. Proposed beam tester and whole CEPC klystron layout are also shown in this paper.
Proceedings of the 7th Int. Particle Accelerator Conf., IPAC2016, Busan, Korea