提高超导腔高功率输入耦合器长期稳定运行性能的研究

当前，射频超导加速技术已经成为强流、高能粒子加速器上的主流技术。超导加速器具有加速效率高和束流品质优等突出优点，但是其研制难度和集成复杂度均远超常温加速器，因此对运行稳定性的要求也更高。其中高功率输入耦合器是超导腔系统的关键部件之一，其承担着功率传输和真空隔离等多重功能。实践证明输入耦合器是超导腔系统中最为脆弱的部件之一，其性能优劣是影响超导加速器长期稳定运行的重要因素之一。但当前国内外各大加速器实验室尚未全面、系统地开展提高耦合器长期运行稳定性的研究。本项目将阐明耦合器陶瓷窗体损坏的微观机制，明确其与耦合器宏观性能表现之间的关系。通过一系列特定的高功率对比实验，形成一套耦合器后处理、高功率测试、安装集成以及在线运行的标准，并从监测、连锁和数据分析等方面改进耦合器运行的连锁保护系统。本研究对提高超导加速器的长期稳定运行意义重大。

Nowadays, superconducting radio frequency (SRF) has become the major technology of accelerating high intensity and high energy particles. Superconducting accelerator has obvious virtues of higher acceleration efficiency and better beam quality, however, it’s far more challenging than the normal conducting accelerator due to more difficult to develop, more complicated to integration and the resulted more demanding requirement on operation stability. The multi-function of power transferring, vacuum shielding and temperature bridging makes the high power input coupler the most critical and complex component of the entire SRF system. Based on the operation experience, input coupler is one of the most flimsy component which greatly affects the stability of long-term operation of the superconducting accelerator. However, the research on improving the stability of long-term operation of the input couplers has not been carried out comprehensively and systematically in accelerator laboratories at home and abroad. This project is aiming to explore the window microscopic damage mechanism and its relationship with the macroscopic performance such as outgassing, multipacting, arc discharging and so on. Based on a series of specific high power contrast experiment, a set of standard on post-processing, high power test, assembly and on-line operation of the high power input coupler is expected to be developed. The interlock control system shall be improved from the view of monitoring, interlock and data archiving and analysis. This study is of great significance to improve the long-term stable operation of the superconducting accelerators.