Progress in the development of high performance 1.3 GHz superconducting cavities

[ Instrument Network Instrument Development ] The research and development personnel of the RF Superconducting and Low Temperature Research Center of the Institute of High Energy Physics, Chinese Academy of Sciences continue to tackle the problem, continuously optimize the processing technology, process and manufacturing process of the superconducting cavity, improve and improve the superconducting cavity surface treatment and testing. Technology, recently, the development work has made a breakthrough, and the performance of the 1.3 GHz superconducting cavity has been greatly improved.

Two 1.3 GHz single-cell superconducting cavities were developed. The acceleration gradient Eacc reached 37 MV/m under 2K vertical test, corresponding to Q0 of about 1×1010; Q0 was about 1.9×1010 under the gradient of 16 MV/m. This is the highest acceleration gradient after processing in the domestic processing and electropolishing process, and its performance is equal to the international advanced level. The test gradients and Q values ​​of the two superconducting cavities are basically the same, which indicates that the development process and electropolishing process of the superconducting cavity explored and created by the research team are stable, and the quality control has achieved remarkable results. There was no significant radiation dose during the vertical test of the superconducting cavity.

In addition, the 1.3 GHz 9-cell liquid-tank superconducting cavity with the same measurement is basically the same as the bare cavity test, which meets the requirements of the first stage of the Shanghai hard X-ray free electron laser project, which will be used for practical projects in the future. The cavity and its batch development laid the foundation.

The 1.3 GHz superconducting cavity is the main cavity type of the Shanghai hard X-ray free electron laser device and the future annular positive and negative electron collider. The acceleration gradient is fully prepared for the implementation of the nitrogen doping process in the next superconducting cavity.

(Original title: Institute of High Energy Physics)