Development of high efficiency klystron at IHEP*

After the discovery of the Higgs boson at LHC, Chinese scientists have planned to build a “Great Collider,” which is a next-generation multinational particle accelerator research facility proposed as a circular electron-positron collider (CEPC) and a super proton-proton collider (SPPC). The CEPC synchrotron radiation power is supposed to be more than 60MW. The efficiency from direct current (DC) to beam power is a very important aspect of the cost of project implementation. Institute of High Energy Physics (IHEP) is developing a higher efficiency klystron of frequency 650 MHz/800 kW with an efficiency goal of around 80%. Different klystron prototypes have been manufactured in the last five years to achieve this goal. Moreover, the beam dynamics of 2860MHz (80MW) klystron is completed and will be manufactured in 2023. The design of 5720 MHz (80 MW &50 MW) klystron for CEPC Linac is also in progress.