High Field Studies on L-band Superconducting Cavities at KEK.

Download or read book High Field Studies on L-band Superconducting Cavities at KEK. written by and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Several 1.3 GHz single-cell and nine-cell niobium cavities were fabricated to attain a higher maximum accelerating gradient and to understand the phenomena limiting it. Vertical cold tests at (almost equal to)1.8 K for the 4 single-cell cavities prepared by various surface treatments have been conducted 15 times. In eight of the tests, maximum accelerating gradients (E{sub acc}, max) of more than 14 MV/m were obtained with no field emission. Furthermore, E{sub acc}, max values of higher than 20 MV/m with a high Q0 value of (almost equal to)101° were achieved repeatedly after heat treatment at 1400 degrees C. Once quenching was observed at E{sub acc}, max (14 (almost equal to) 20 MV/m), however, a common phenomenon resulting in Q0-deterioration occurred in every test. The cavity performances and the phenomenon at high fields are reported in this paper.