First operational experience with the HIE-Isolde helium cryogenic system including several RF cryo-modules

[摘要] The High Intensity and Energy ISOLDE (HIE-ISOLDE) upgrade project at CERN includes the deployment of new superconducting accelerating structures operated at 4.5 K (ultimately of six cryo-modules) installed in series, and the refurbishing of the helium cryo-plant previously used to cool the ALEPH magnet during the operation of the LEP accelerator from 1989 to 2000. The helium refrigerator is connected to a new cryogenic distribution line, supplying a 2000-liter storage dewar and six interconnecting valve boxes (i.e jumper boxes), one for each cryo-module. After a first operation period with one cryo-module during six months in 2015, a second cryo-module has been installed and operated during 2016. The operation of the cryo-plant with these two cryo-modules has required significant technical enhancements and tunings for the compressor station, the cold-box and the cryogenic distribution system in order to reach nominal and stable operational conditions. The present paper describes the commissioning results and the lessons learnt during the operation campaign of 2016 together with the preliminary experience acquired during the 2017 operation phase with a third cryo-module.

[发布机构] European Organization for Nuclear Research, CERN, Technology Department, Geneva 23; CH-1211, Switzerland^1

[效力级别] 物理学 [学科分类] 材料科学（综合）

[关键词] Accelerating structure;Compressor stations;Distribution lines;Distribution systems;Helium refrigerators;Operational conditions;Operational experience;Technical enhancements