Grant: Subatomic Physics Envelope - Research Tools and Instruments

This grant request is for equipment which will put the proponents at the forefront of the development of new materials and new processing techniques for superconducting radio-frequency (SRF) cavities for use in particle accelerators. Developments will include the production and testing of Nb3Sn samples and cavities as well as developing and optimizing the performance of bulk Nb. The proposal goal is to secure a critical mass of equipment to enable breakthroughs that attack the major questions facing the SRF community today. The present proposal is calling for funds to add equipment to leverage existing SRF and material science infrastructure. For sample characterization unique in the world a new spectrometer would be added to the beta-NMR facility ($147k). The facility would allow measurements of the magnetic field penetration in the sample near the limits of the Meissner state as a function of depth through the London layer. Further diagnosis of samples would be done with the addition of a sample testing resonant cavity ($88k) that would be used to test the samples with rf fields to compare fundamental characterizations in beta-NMR with rf measurements. Particular heat treatments developed through beta NMR and the rf sample cavity would then be applied to single cell 1.3GHz cavities using an rf induction oven (existing) for testing in the TRIUMF multi-purpose cryostat. Funds would be used to complete the data acquisition system ($65K) to allow complete cavity characterization of single cell cavities of each of the new treatments. The T-map would ensure that the cavity test, a global measurement, is indicative of the treatment and not a local hot spot due to systematic loss. An upgrade to the multi-purpose cryostat ($15k) would be done to utilize the T-map system. In addition to cavity rf tests at 1.3GHz we propose to fabricate two coaxial resonators ($149k) that would also fit into the rf induction oven and would allow unique tests on the performance of cavity treatments at frequencies from 200MHz to 1.2GHz. The rf induction oven would also be used to develop Nb3Sn coating methods by the addition of a new insert ($36k). Initially samples would be produced and tested in beta-NMR and the rf sample cavity. Later single cell 1.3GHz cavities and the coaxial resonator would be coated to look at the effectiveness of Nb3Sn as a function of frequency and geometry. The total funds request is $499k over three years. The proposed research equipment would produce a truly unique center for fundamental SRF research where precise probes of magnetism at the London layer are coupled with rf sample testing cavities and the results extended to whole cavities to give a complete picture of the mechanisms behind rf losses over a broad rf frequency range. At the core of the equipment request is the quest to make a breakthrough. Through this quest students and young professionals will be trained while pursuing solutions to compelling questions.