Fastest Electropolishing Technique on Niobium for Particle Accelerators
Field emission on the inner surfaces of niobium (Nb) superconducting radio frequency (SRF) cavities is still one of the major obstacles for reaching high accelerating gradients for SRF community. Our previous experimental results [1] seemed to imply that the threshold of field emission was related to the thickness of Nb surface oxide layers. In this contribution, a more detailed study on the influences of the surface oxide layers on the field emission on Nb surfaces will be reported. By anodization technique, the thickness of the surface pentoxide layer was artificially fabricated from 3nm up to 460nm. A home-made scanning field emission microscope (SFEM) was employed to perform the scans on the surfaces. Emitters were characterized using a scanning electron microscope together with an energy dispersive x-ray analyzer. The experimental results could be understood by a simple model calculation based on classic electromagnetic theory as shown in Ref.1. Possibly implications for Nb SRF cavity applications from this study will be discussed.
- Research Organization:
- Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
- Sponsoring Organization:
- USDOE Office of Science (SC)
- DOE Contract Number:
- AC05-06OR23177
- OSTI ID:
- 1029368
- Report Number(s):
- JLAB-ACC-11-1438; DOE/OR/23177-1915; TRN: US1105766
- Resource Relation:
- Conference: IPAC2011, 4-9 Sep 2011, San Sebastian, Spain
- Country of Publication:
- United States
- Language:
- English
Similar Records
Effects of the Thickness of Niobium Surface Oxide Layers on Field Emission
Study of Low Temperature Baking Effect on Field Emission on Nb Samples Treated by BEP, EP, and BCP