Publications
Publication Information
Title | Analysis of RF losses and material characterization of samples removed from a Nb3Sn coated superconducting RF cavity |
Authors | Uttar Pudasaini, Grigory Eremeev, Charles Reece, Jay Tuggle, Michael Kelley |
JLAB number | JLAB-ACC-19-3058 |
LANL number | (None) |
Other number | DOE/OR/23177-4795 |
Document Type(s) | (Journal Article) |
Category: | SRF Technology |
Associated with EIC: | No |
Supported by Jefferson Lab LDRD Funding: | No |
Funding Source: | Nuclear Physics (NP) |
Other Funding: | High Energy Physics (HEP) |
Journal Compiled for Superconductor Science and Technology Volume 33 Issue 4 Page(s) 045012 Refereed | |
Publication Abstract: | Nb3Sn (Tc~18 K and Hsh~400 mT) is a prospective material to replace Nb (Tc~9 K and Hsh~200 mT) in SRF accelerator cavities for significant cost reduction and performance enhancement. Because of its material properties, Nb3Sn is best employed as a thin film (coating) inside an already built RF cavity structure. A particular test cavity noted as C3C4 was a 1.5 GHz single-cell Nb cavity, coated with Nb3Sn using Sn vapor diffusion process at Jefferson Lab. Cold measurements of the coated cavity indicated the superconducting transition temperature of about 18 K. Subsequent RF measurements indicated field-dependent surface resistance both at 4.3 K and 2.0 K. After initial cold measurements, the cavity RF loss distribution was studied with a thermometry mapping system. Loss regions were identified with thermometry and were cut out for material analysis. The presence of significantly thin patchy regions and other carbon-rich defects is associated with strong local field-dependent surface resistance. This paper summarizes RF and thermometry results correlated with material science findings. |
Experiment Numbers: | |
Group: | Accel Division Management |
Document: | |
DOI: | https://doi.org/10.1088/1361-6668/ab75a8 |
Accepted Manuscript: | C3C4_CutoutPaper_30Aug2019.pdf |
Supporting Documents: | |
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