Grant: Subatomic Physics Envelope - Individual

The proposed research deals with Fundamental studies in superconducting niobium RF resonators (cavities).Superconducting rf (SRF) cavities are the fundamental building blocks of modern linear accelerators. Theaccelerators have applications as research tools in sub-atomic physics, and in a number of industrial andmedical applications. The proposal presented here deals with a directed research program for the study offundamental issues that limit cavity performance.One of the outstanding scientific issues related to niobium (a marginal Type-II superconductor) SRF cavities is the occurrence of field dependent losses in the walls of the cavity. These losses typically increase sharply at an onset peak magnetic field ~ 80-100 mT well below the expected onset of the mixed state. Understanding the causes and the physics behind these anomalous losses is a key link to improving the performances of superconducting cavities. The superconducting rf lab at TRIUMF, unique in Canada, and one of the few such facilities in the world, was initiated in 2003 by the PI of this proposal. The main initial goal of the lab was to construct a superconducting heavy ion linac. A first phase, consisting of 20 bulk niobium quarter wave cavities, was completed in 2006 and operated with cavity performance significantly above other similar facilities in the world. A second phase recently completed adds 20 more cavities constructed through a technical transfer between the TRIUMF SRF lab and a local Canadian company, PAVAC. Over the last few years the research interest of the TRIUMF SRF group has expanded to include research into fundamental superconducting rf topics. The aim is to leverage the investment in the present SRF infrastructure as well as the existing experimental facilities at TRIUMF coupled to the local university environment at UBC, U. Vic. and SFU to create a unique center for SRF research in Canada. The research program that is the subject of this proposal is broad based and will leverage existing equipment and infrastructure to grow the lab as a training ground for young researchers in the science and technology of accelerators.