A dielectric-assist accelerating (DAA) cavity is a standing-wave accelerating cavity that attains a Q-value of over 100,000 at room temperature by using the reflection of the dielectric layer; the DAA cavity is expected to be used with a small rf power source and high-duty operation. Thus far, the maximum accelerating field of DAA cavities has been limited to a few MV/m by the multipactor discharges. Multipactor discharges are widely observed in the accelerator field, and their suppression has been studied to improve accelerator performance. By applying a diamondlike carbon (DLC) coating to reduce the secondary electron emission coefficient without sacrificing the Q-value of the cavity, we have demonstrated that a C-band rf pulse with a pulse length of $5.4[\mu \mathrm{s}]$ can be injected into a DAA cavity with a field of more than 10 [MV/m] while suppressing the multipactor discharges.

中文翻译：

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通过类金刚石碳涂层抑制介电辅助加速结构中的多峰

介电辅助加速（DAA）腔是一种驻波加速腔，通过使用介电层的反射在室温下达到Q值超过100,000。DAA腔有望在小型射频电源和高负载下使用。到目前为止，通过多极放电，DAA腔的最大加速场已被限制在几个MV / m。在加速器领域中广泛观察到多步放电，并且已经对其抑制进行了研究以提高加速器性能。通过施加类金刚石碳（DLC）涂层来降低二次电子发射系数而又不牺牲腔体的Q值，我们证明了一个C波段rf脉冲的脉冲长度为$5.4[\mu \mathrm{s}]$ 可以将其注入具有大于10 [MV / m]的电场的DAA腔中，同时抑制多步放电。