RF performance sensitivity to tuning of Nb3Sn coated CEBAF cavities

Conference · Fri Nov 01 00:00:00 EDT 2019

OSTI ID:1648137

Eremeev, G. V. ^[1]; Crahen, W. ^[1]; Henry, J. ^[1]; Marhauser, F. ^[1]; Reece, C. E. ^[1]; Pudasaini, U. ^[2]

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1. Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
2. College of William and Mary, Williamsburg, VA (United States)

Nb3Sn has the potential to surpass niobium as the material of choice for SRF applications. The potential of this material stems from a larger superconducting energy gap, which leads to expectations of a higher RF critical field and a lower RF surface resistance. The appeal of better superconducting properties is offset by the relative complexity of producing practical Nb3Sn structures, and Nb3Sn sensitivity to lattice disorder challenges the use of the material for practical applications. Such sensitivity is indirectly probed during SRF cavity development, when the cavity is tuned to match the desired accelerator frequency. In the course of recent experiments we have coated and tuned several multi-cell cavities. Cold RF measurements before and after tuning showed degradation in cavity performance after tuning. The results of RF measurement were compared against strain evolution on Nb3Sn surface during tuning based on CST and ANSYS models.

• Research Organization: Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Nuclear Physics (NP)
• DOE Contract Number: AC05-06OR23177
• OSTI ID: 1648137
• Report Number(s): JLAB-ACC-19-2974; DOE/OR/23177-4727
• Country of Publication: United States
• Language: English