New progress on beam availability and reliability of PKU high intensity CW proton ECR ion source

• Published in: Chinese physics B Vol. 26; no. 2; pp. 345 - 348
• Main Author: 彭士香 张艾霖 任海涛 徐源 张滔 张景丰 温佳美 郭之虞 陈佳洱
• Format: Journal Article
• Language: English
• Published: 01.02.2017
• Subjects: ECR离子源; 光束功率; 北京大学; 可用性; 可靠性; 操作过程; 质子源; 高强度
• ISSN: 1674-1056; 2058-3834
• DOI: 10.1088/1674-1056/26/2/025206

The stability and reliability of an ion source and its beam availability are extremely significant for any accelerator,especially for those high current long term CW operation ones like ADS. Although the first high quality 306-hours continuous wave（CW） operating curve at 50 m A@35 ke V has been successfully obtained with a standard compact 2.45 GHz ECR ion source at Peking University（PKU）, but the uncertainties that caused beam trips before are unacceptable during an accelerator real operation and should be eliminated. Meanwhile, no permission will be given when the beam power is upgraded from 50 m A@35 ke V to 50 m A@50 ke V. To improve the PKU CW proton source quality, several upgrades were done recently. After those improvements, a new long term CW proton beam experiment at 50 m A@50 ke V was carried out in June 2016. The total running time is 300.5 hours, including near 6 hours ion source preparation and 294 hours non-disturb continuous operation. Within the continuous 13 days operation, no beam-off happened, no spark was observed,no beam drop appeared, no interrupting action was needed, and only a few beam fluctuations caused by the air conditional failure occurred. Beam availability and reliability within the 294 hours is 100%. The root-mean-square（RMS） emittance of this 50 m A@50 ke V CW proton beam is about 0.186 π.mm.mrad. A careful inspection of the ion source was done after this long term operation and no obvious damage was found. The restart experimental results obtained after the ion source inspection prove the high repeatability of PKU PMECRIS. In addition, a 130-m A H＋beam was obtained at 50 k V with duty factor of 10%（100 Hz/1 ms） with this source. Details will be presented in this paper.