1.5GHz超导加速腔双输入耦合器研究  

Study on twin input coupler for a 1.5-GHz superconducting cavity

作　　者：谢新华[1,2,3] 王岩[1,2] 马震宇[1,2] 是晶[1,2] 罗琛[1,2] 李正[1,2] 毛冬青[1,2] 封自强[1,2] 侯洪涛[1,2] 刘建飞[1,2] 

机构地区：[1]中国科学院上海应用物理研究所嘉定园区,上海201800 [2]上海市低温超导高频腔技术重点实验室,上海201800 [3]中国科学院大学,北京100049

出　　处：《核技术》2016年第6期15-20,共6页Nuclear Techniques

基　　金：国家自然科学基金(No.11335014)资助~~

摘　　要：本实验室设计的1.5 GHz 5-cell超导腔设计工作加速梯度为15-20 MV·m^(-1),至少需要使用两支输入耦合器才能满足高流强运行要求。借助三维电磁仿真模拟软件CST(Computer Simulation Technology),完成了相应的输入耦合器的电磁仿真,驻波比小于1.05的频带宽度达到18 MHz。从理论上计算加速腔双端口功率馈入,并通过铜腔双输入实验进行验证。结果表明,当两端均为欠耦合时,双输入对每个端口耦合度起到增强的作用;但当两者均为过耦合且差异较大时,耦合度小的一端则被减弱,甚至出现欠耦合的情况。对横向力场的计算显示,即使插入深度相差1 mm,使用双输入耦合器所引起的横向作用力仍比使用单耦合器情况小一个量级。Background The 1.5-GHz 5-cell superconducting cavity designed by the Shanghai Key Laboratory ofCryogenics ＆ Superconducting Radio Frequency Technology was optimized to accelerate a high current electronbeam under continuous wave （CW） operation mode. Purpose： Considering the accelerating gradient 15-20 MV·m-1,it is necessary to use twin input coupler. Methods： Electromagnetic simulations of the input coupler wereimplemented using CST （Computer Simulation Technology）, and the results showed a 18-MHz bandwidth wherestanding-wave ratio was better than 1.05. Power feeding by two couplers was calculated theoretically and testified ona set-up. Results： Theoretical derivation and experimental results showed an enhancing when both couplers wereunder coupled but a reduction to the weaker coupled one when both couplers were over coupled. Results fromsimulations showed that transverse kick to beam can be diluted drastically even when difference of insert depths is1 mm. Conclusion： Adopting twin input coupler is the only option for high average beam current CW accelerator.

关 键 词：双输入耦合器 耦合度 耦合器踢束效应 

分 类 号：TL503.2[核科学技术—核技术及应用]