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arXiv · 1807.03473

Operation of normal-conducting RF cavities in multi-tesla magnetic fields for muon ionization cooling: a feasibility demonstration

Daniel Bowring·Alexey Kochemirovskiy·Yagmur Torun·Chris Adolphsen·Alan Bross·Moses Chung·Ben Freemire·Lixin Ge·Andrew Haase·Peter Lane·Maria Leonova·Derun Li·Zenghai Li·Ao Liu·Tianhuan Luo·David Martin·Alfred Moretti·David Neuffer·Ralph Pasquinelli·Mark Palmer·David Peterson·Milorad Popovic·Diktys Stratakis·Katsuya Yonehara
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Abstract

Ionization cooling is the preferred method for producing bright muon beams. This cooling technique requires the operation of normal conducting, radio-frequency (RF) accelerating cavities within the multi-tesla fields of DC solenoid magnets. Under these conditions, cavities exhibit increased susceptibility to RF breakdown, which can damage channel components and imposes limits on channel length and transmission efficiency. We present a solution to the problem of breakdown in strong magnetic fields. We report, for the first time, stable high-vacuum, copper cavity operation at gradients above 50 MV/m and in an external magnetic field of three tesla. This eliminates a significant technical risk that has previously been inherent in ionization cooling channel designs.

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Daniel Bowring, Alexey Kochemirovskiy, Yagmur Torun, Chris Adolphsen, Alan Bross, Moses Chung, Ben Freemire, Lixin Ge, Andrew Haase, Peter Lane, Maria Leonova, Derun Li, Zenghai Li, Ao Liu, Tianhuan Luo, David Martin, Alfred Moretti, David Neuffer, Ralph Pasquinelli, Mark Palmer, David Peterson, Milorad Popovic, Diktys Stratakis, Katsuya Yonehara. 2018-07-10. Operation of normal-conducting RF cavities in multi-tesla magnetic fields for muon ionization cooling: a feasibility demonstration. https://doi.org/10.1103/physrevaccelbeams.23.072001

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