论文标题
一个紧凑的低场，宽带匹配部分，用于外部动力的X波段介电加速结构
A compact, low field, broadband matching section for externally-powered X-band dielectric-loaded accelerating structures
论文作者
论文摘要
在技术上，有效将外部射频（RF）功率与圆柱电介质加速（DLA）结构相结合，尤其是当DLA结构具有较高的介电常数时，这在技术上具有挑战性。本文介绍了一种新颖的匹配部分设计，用于将RF功率从圆形波导到X波段DLA结构，其介电常数EPSILON_R = 16.66和一个损耗切线TAN_DELTA = 0.0000343。它由一个非常紧凑的介电磁盘组成，宽度为2.035 mm，倾斜角度为60度，导致在低RF场的宽带耦合，这有可能在高功率环境中生存。为了防止急剧的介电拐角断裂，还增加了45度倒角。还详细研究了由金属涂层和外部厚的铜夹克之间的金属夹具引起的微观真空间隙。通过优化，超过99％的RF功率耦合到DLA结构中，最大电磁场位于DLA结构。关于几何参数和全组装结构的机械设计的公差研究也被作为现实制造的参考。
It has been technically challenging to efficiently couple external radiofrequency (RF) power to cylindrical dielectric-loaded accelerating (DLA) structures, especially when the DLA structure has a high dielectric constant. This paper presents a novel design of matching section for coupling the RF power from a circular waveguide to an X-band DLA structure with a dielectric constant epsilon_r=16.66 and a loss tangent tan_delta=0.0000343. It consists of a very compact dielectric disk with a width of 2.035 mm and a tilt angle of 60 degree, resulting in a broadband coupling at a low RF field which has the potential to survive in the high-power environment. To prevent a sharp dielectric corner break, a 45 degree chamfer is also added. A microscale vacuum gap, caused by metallic clamping between the thin coating and the outer thick copper jacket, is also studied in detail. Through optimizations, more than 99% of RF power is coupled into the DLA structure, with the maximum electromagnetic fields located at a DLA structure. Tolerance studies on the geometrical parameters and mechanical design of the full-assembly structure are also carried out as a reference for realistic fabrication.
