The influence of chemical treatments on the superconducting properties of technical niobium materials and their effect on the performance of superconducting radio frequency cavities

Journal Article · Wed Sep 16 04:00:00 EDT 2009 · Superconductor Science and Technology

DOI:https://doi.org/10.1088/0953-2048/22/10/105014· OSTI ID:1999570

Roy, S. B.; Myneni, G. R.; Sahni, V. C.

We present the results of a study of superconducting response in the niobium material used in the fabrication of high accelerating gradient (>25 MVm-1) superconducting radio frequency (SC-RF) cavities. These results clearly show that the typical surface chemical treatment deployed during the fabrication of SC-RF cavities affects the superconducting properties of pure niobium materials. Such SC-RF cavities operating at 2 K are often found to show anomalous RF losses, causing either a strong degradation of the quality factor or a thermal breakdown for cavity magnetic fields between 1 and 1.5 kOe. The results of our study suggest a correlation between the field for the first flux-line penetration in these chemically treated technical niobium materials and the reported onset field of anomalous losses in the SC-RF cavities.

• 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: 1999570
• Report Number(s): JLAB-ACC-09-986; DOE/OR/23177-1001
• Journal Information: Superconductor Science and Technology, Journal Name: Superconductor Science and Technology Journal Issue: 10 Vol. 22; ISSN 0953-2048
• Country of Publication: United States
• Language: English