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 cooling channel components and imposes limits on channel length and transmission efficiency. We report, for the first time, stable high-vacuum, normal-conducting cavity operation at gradients of 50 MV/m in an external magnetic field of three tesla, through the use of beryllium cavity elements. This eliminates a significant technical risk that has previously been inherent in ionization cooling channel designs.

中文翻译：

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在多特斯拉磁场中用于μ子电离冷却的正向导通射频腔的操作：可行性论证

电离冷却是产生明亮的介子束的首选方法。这种冷却技术需要在直流螺线管磁体的多特斯拉磁场内正常传导射频（RF）加速腔。在这些条件下，空腔对RF击穿的敏感性增加，这会损坏冷却通道组件，并限制通道长度和传输效率。我们首次报告了通过使用铍腔体元件，在三个特斯拉的外部磁场中，以50 MV / m的梯度在高真空，正常导电的腔体中稳定运行的情况。这消除了以前电离冷却通道设计固有的重大技术风险。