750 keV射频四极注入器射频结构的优化

 设计了750 keV，201.25 MHz的RFQ注入器的射频结构,对四杆型RFQ结构进行了简要的理论分析,在束流动力学设计的基础上，对射频结构进行了优化。研究了四杆型RFQ结构中支撑板高度、宽度、厚度、间距、形状、外腔体半径等因素对射频特性的影响，进行了优化设计并给出了主要的结构参数及射频特性的设计结果。优化设计得到的四杆型RFQ腔体长度126 cm,在极间电压80 kV时，峰值功率损耗为115.95 kW，二极场因子为1.004，电场沿轴向分布比较均匀，偏差小于3.5%,满足了物理需求。

RF optimization design of a 750 keV radio frequency quadrupole injector

The RF design of a 201.25 MHz, 750 keV RFQ injector is described. A four-rod structure is chosen for the RF design. The essential parameters are obtained from the beam dynamics design. The structure parameters, including the height, width, thickness, distance，shape of supporting arms, radius of outer cavity, are optimized by numerical simulation. When the inter-electrode voltage is 80 kV, the peak power loss is 115.95 kW, the dipole factor is 1.004 and the field flatness is within 3.5%. The result of the RF structure design satisfies the physics requirement well.