Abstract
Niobium is used to fabricate superconducting radio frequency accelerator modules because of its high critical temperature, high critical magnetic field, and easy formability. Recent experiments have shown a very significant improvement in performance (over 100%) after a high‐temperature bake at 1400 °C for 3 h. SIMS analysis of this material showed the oxygen profile was significantly deeper than the native oxide with a shape that is indicative of diffusion. Positive secondary ion mass spectra showed the presence of Ti with a depth profile similar to that of O. It is suspected that Ti is associated with the performance improvement. The source of Ti contamination in the anneal furnace has been identified, and a new furnace was constructed without Ti. Initial results from the new furnace do not show the yield improvement. Further analyses should determine the relationship of Ti to cavity performance. Copyright © 2014 John Wiley & Sons, Ltd.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
