Muon Capture, Phase Rotation, and Precooling in Pressurized RF Cavities

79221 Bright muon beams are required for muon colliders, neutrino factories, amd intense muon sources. The muons must be produced by smashing high energy protons into a target to generate pions that then decay into a diffuse cloud of muons. The muons must be: (1) captured in strong magnetic fields, (2) bunched by strong RF electric fields, and (3) precooled by passing the beam through a low-Z energy absorber. As presently envisioned, these three processes are done sequentially, with corresponding increases in inefficiency and expense, as well as a lost opportunity to perform a radio frequency (RF) phase-energy rotation to reduce momentum spread. In this project, pressurized RF cavities, presently being developed for later stages of muon cooling, will be developed to work in the extreme conditions near the production target. As a result, all three of the presently envisioned processes will be allowed to happen simultaneously and, in addition, allow for the addition of phase-energy rotation. In Phase I, simulations will be conducted to compare the potential benefits of the combined capture, phase rotation, bunching, and precooling to the conventional sequential approach. The present status of the high pressure RF cavity development program at Fermilab will be evaluated, and a plan will be generated to continue the experimental cavity development program. Commercial Applications and Other Benefits as described by the awardee: The generation of intense muon beams with small emittances should benefit many branches of science, where such beams are needed for muon colliders, Higgs and neutrino factories, bright muon sources, and studies of muon catalyzed fusion.