Operation of domestic 500 MHz superconducting cavity for BEPC Ⅱ
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摘要: 北京正负电子对撞机二期(BEPCⅡ),国产500 MHz超导腔经过紧张的安装调试于2017年10月正式投入带束流运行。首先对此国产超导腔两次降温调试的相关参数进行了监测和对比分析;其次研究了通过高功率老练的方法改善超导腔的品质因数,并实时监测超导腔老练过程中的辐射剂量;最后对超导腔的带束流运行情况进行了介绍分析。结果表明:BEPCⅡ国产500 MHz超导腔虽然放置了6年,但是状态良好,通过高功率老练能够降低超导腔的辐射剂量,改善其性能,完全满足束流运行要求。Abstract: The domestic 500 MHz superconducting cavity for BEPC Ⅱ has been installed and beam tested in October 2017.The related parameters of cavity during cooling down have been monitored and analyzed, the quality factor of the cavity has been improved by high RF (radio frequency) power aging, and the radiation dose has been monitored, and the situation of cavity running with beam has been analyzed.The results show that the cavity has been working very well though it had been idle for six years, and the performance of the cavity has been improved through high RF power aging.The performance of the cavity completely meets the demands of beam running.
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Key words:
- RF superconducting /
- storage ring /
- beam experiment /
- radiation monitoring
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表 1 BEPCⅡ 500 MHz超导腔主要设计参数
Table 1. Main design parameters of BEPC'sⅡ 500 MHz superconducting cavity
cavity voltage/MV Q0(unloaded quality factor) frequency /MHz QL(loaded quality factor) coupler power (total reflection/kW) HOM power/kW designed 1.5~2.0 >5.0×108 499.8±0.05 1.7×105(1±10%) 50 >4 measured 2.17 7.67×108 499.8 1.33×105 100 9 -
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