Fermilab, Batavia, Illinois, USA
A new test stand dedicated to SRF cryomodule testing, CMTS1, has been commissioned and is now in operation at Fermilab. The first device to be cooled down and powered in this facility is the prototype 1.3 GHz cryomodule assembled at Fermilab for LCLS-II. We describe the demonstrated capabilities of CMTS1, report on steps taken during commissioning, provide an overview of first test results, and survey future plans.
Fermilab, Batavia, Illinois, USA
ANL, Argonne, Illinois, USA
The PIP-II project at Fermilab requires fifteen 650 MHz SRF cryomodules as part of the 800 MeV LINAC that will provide a high intensity proton beam to the Fermilab neutrino program. A total of fifty-seven high-performance SRF cavities will populate the cryomodules and will operate in both pulsed and continuous wave modes. These cavities will be processed and prepared for performance testing utilizing adapted cavity processing infrastructure already in place at Fermilab and Argonne. The processing recipes implemented for these structures will incorporate state-of-the art processing and cleaning techniques developed for 1.3 GHz SRF cavities for the ILC, XFEL, and LCLS-II projects. This paper describes the details of the processing recipes and associated chemistry, heat treatment, and cleanroom processes at the Fermilab and Argonne cavity processing facilities. This paper also presents single and multi-cell cavity test results with quality factors above 5·1010 and accelerating gradients above 30 MV/m.
Fermilab, Batavia, Illinois, USA
The ambient magnetic field at the SRF cavity surface of the LCLS-II 1.3 GHz cryomodules is specified to be less than 0.5 μT (5 mG). Multiple methods were designed to lower the magnetic fields inside the prototype cryomodule. The resulting ambient magnetic field in this cryomodule just prior to its first cool down was <0.15 μT (1.5 mG), as measured using fluxgates inside and outside the cavity helium vessels.