The international review meeting on the Radio Frequency (RF) system for the High Energy Photon Source (HEPS) project was held at IHEP on Dec. 19-20, 2023. Eight experienced scientists and technical experts from European Organization for Nuclear Research (CERN), the Paul Scheer Institute (PSI) in Switzerland, Deutsches Elektronen-Synchrotron (DESY) in Germany, the High Energy Accelerator Research Organization (KEK) in Japan, Peking University, Tsinghua University and Shanghai Advanced Research Institute, formed the review committee chaired by Dr. Rama Calaga from CERN and co-chaired by Dr. Zheqiao Geng from PSI. More than 30 people attended the meeting including the review committee, HEPS management, HEPS RF team, and HEPS Project Management Office.

The deputy director of IHEP and deputy manager of the HEPS project, Yuhui Li, welcomed the review committee and the participants. He pointed out that the RF system is one of the key building blocks of the HEPS accelerator responsible for the storage-ring RF and the booster RF. Much progress has been made in the past few years. He hoped that the review committee would provide professional opinions and advice on the HEPS RF system.

Pei Zhang, the RF system leader, first introduced the design, management and overall progress of the HEPS RF system, followed by 10 dedicated presentations given by the RF team members covering the entire scope of the RF system including cavities, power couplers, higher order modes, high-power RF, low-level RF, commissioning and operations. In addition, warm discussions and in-depth communications with the RF team were conducted between the review committee and the RF team during the meeting.

The committee congratulated the RF team for the very significant progress and achievements on all fronts of the RF system and was impressed by the very motivated and dynamic team covering a huge range of technologies. The committee also emphasized that the HEPS project is indirectly contributing to the SRF community by pushing the performance limits of low-frequency (β=1) SCRF technology for high-current storage rings. Important constructive opinions and recommendations on technical issues were presented by the committee while a full review report will be submitted to the RF team in Jan 2024. The experts also gave recommendations on planning and direction for the technical design stage. The meeting was closed by Ping He, Head of HEPS Accelerator.

The review committee also visited the HEPS site and the Platform of Advanced Photon Source Technology R&D (PAPS) in Huairou.

Participants of the International Review Meeting on HEPS RF System

 Members of the review committee visiting HEPS storage ring