학술논문

Change of RF superconductivity parameters induced by heat treatment on niobium cavities
Document Type
Conference
Source
PACS2001. Proceedings of the 2001 Particle Accelerator Conference (Cat. No.01CH37268) Particle accelerator conference Particle Accelerator Conference, 2001. PAC 2001. Proceedings of the 2001. 2:1056-1058 vol.2 2001
Subject
Fields, Waves and Electromagnetics
Engineered Materials, Dielectrics and Plasmas
Nuclear Engineering
Robotics and Control Systems
Radio frequency
Superconductivity
Heat treatment
Surface contamination
Surface treatment
Thermal quenching
Thermal conductivity
Niobium
Chemicals
Annealing
Language
Abstract
We have investigated the thermal quench evolution of a Niobium cavity, chemically polished, during ultra high vacuum annealings from 100 to 800/spl deg/C. Ten cavities have been tested before heat treatment (HT) and the results show a good agreement with the BCS theory for a diffuse reflection of the conduction electrons on the metal surface. All along the HT we have clearly identified at first the oxygen diffusion from the surface, followed by a cleaning phase of the RF surface and finally, above 800/spl deg/C, the appearance of a new contamination probably due to the furnace residual gases. All this events involve consequences for the quench position through the thermal conductivity.