RF CAVITY PERFORMANCE IN THE ISAC-II SUPERCONDUCTING HEAVY ION LINAC

The ISAC-II superconducting linac consists of forty quarter wave bulk niobium cavities. There are eight and twelve 106MHz cavities at beta=5.7% and 7.1% respectively and twenty cavities at 141MHz at beta=11%. The first twenty have been operating since 2006 (Phase I) and the remainder have been installed for first commissioning in April 2010 (Phase II). Cavity performance statistics of the 2006 cavities have been accumulated to look for signs of systematic degradation in performance. In addition single cavity test results and in situ characterization tests of the first operation are recorded. The cavity performance is summarized and discussed.