Title :
R&D in progress to overcome field emission in superconducting accelerator cavities
Author :
Shu, Q.S. ; Gendreau, K. ; Hartung, W. ; Kirchgessner, J. ; Moffat, D. ; Noer, R. ; Padamsee, H. ; Rubin, D. ; Sears, J.
Author_Institution :
Lab. of Nucl. Studies, Cornell Univ., Ithaca, NY, USA
Abstract :
Systematic studies are in progress for understanding, controlling, and eliminating field emission (FE) in superconducting cavities so that higher gradients can be achieved for application of superconducting cavities to future linear colliders. In exploration of potential cures, UHV heating above 1000°C was used as the final surface treatment on one-cell, 1.5 GHz cavities. A new technique has been developed to extend temperatures to 1350°C and heating times to 4 h without degrading the purity of the wall. The average accelerating fields increased by 80% in comparison with similar chemically prepared cavities. The best cavity reached surface electric (magnetic) fields of 53 MV/m (1350 Oe). The influence of various treatments on the properties of 50 emitters analyzed is presented. In other studies, it is found that the effectiveness of He processing continues as higher RF power levels are used
Keywords :
beam handling equipment; linear accelerators; superconducting devices; surface treatment; He processing; UHV heating; average accelerating fields; field emission; heating times; linear colliders; superconducting accelerator cavities; surface treatment; Acceleration; Chemicals; Control systems; Degradation; Heat treatment; Heating; Iron; Superconducting magnets; Surface treatment; Temperature;
Conference_Titel :
Particle Accelerator Conference, 1989. Accelerator Science and Technology., Proceedings of the 1989 IEEE
Conference_Location :
Chicago, IL
DOI :
10.1109/PAC.1989.73089
