Tests Of The Extended Range SRF Cavity Tuners For The LCLS-II-HE Project*

C. Contreras-Martinez; T. Arkan; A. Cravatta; B. Hartsell; J. Kaluzny; T. Khabiboulline; Y. Pischalnikov; S. Posen; G. Romanov; JC. Yun

arXiv · 2208.06320

Tests Of The Extended Range SRF Cavity Tuners For The LCLS-II-HE Project*

C. Contreras-Martinez·T. Arkan·A. Cravatta·B. Hartsell·J. Kaluzny·T. Khabiboulline·Y. Pischalnikov·S. Posen·G. Romanov·JC. Yun

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Abstract

The LCLS-II HE superconducting linac can produce multi-energy beams by supporting multiple undulator lines simultaneously. This could be achieved by using the cavity SRF tuner in the off-frequency detune mode. This off-frequency operation method was tested in the verification cryomodule (vCM) and CM 1 at Fermilab at 2 K. In both cases, the tuners achieved a frequency shift of -565$\pm$80 kHz. This study will discuss cavity frequency during each step as it is being assembled in the cryomodule string and finally when it is being tested at 2 K. Tracking the cavity frequency helped enable the tuners to reach this large frequency shift. The specific procedures of tuner setting during assembly will be presented.

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C. Contreras-Martinez, T. Arkan, A. Cravatta, B. Hartsell, J. Kaluzny, T. Khabiboulline, Y. Pischalnikov, S. Posen, G. Romanov, JC. Yun. 2022-08-12. Tests Of The Extended Range SRF Cavity Tuners For The LCLS-II-HE Project*. https://arxiv.org/abs/2208.06320

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