The vacuum oscillators generally utilize high current annular relativistic electron beams to generate high-power microwaves. The annular electron beams are usually guided and focused by strong axial magnetic fields. A permanent magnet is developed for the application of annular electron beams. The configuration of the permanent magnet is based on the Halbach structure. A new method is proposed to design this solenoidal permanent magnet. The permanent magnet flux source can generate a 0.88 T axial magnetic field at the interaction region and a peak field of 0.94 T. The diameter of its clear bore is 50 mm. The total weight of the permanent magnet is 320 kg. The design, fabrication, and test results are presented in this article.

中文翻译：

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环形电子束引导和聚焦螺线管永磁体的研究


真空振荡器通常利用高电流环形相对论电子束来产生高功率微波。环形电子束通常由强轴向磁场引导和聚焦。永磁体是为环形电子束的应用而开发的。永磁体的配置基于 Halbach 结构。提出了一种设计这种螺线管永磁体的新方法。该永磁磁通源在相互作用区可产生0.88 T的轴向磁场，峰值磁场为0.94 T。其通孔直径为50 mm。永磁体的总重量为320千克。本文介绍了设计、制造和测试结果。