Superconducting CH structure

Abstract

The superconducting CH structure is a novel multicell cavity for the acceleration of protons and ions in the low and intermediate energy regime. The CH structure is a cross-bar-type cavity; it is the first superconducting low energy multicell cavity operated in an H mode. A superconducting CH-prototype cavity with 19 gaps at $\beta =0.1$ has been built and tested successfully. Maximum surface fields of $25\mathrm{MV}/\mathrm{m}$ and a corresponding effective cavity voltage gain of 3.7 MV have been achieved. In this paper the development and the tests of this new cavity are presented. This includes also tuning and coupling methods as well as a comparison with other low energy cavities.