1.3GHz 9单元Ichiro型模型铜腔的预调谐

Pretuning of 1.3GHz 9-cell Ichiro copper cavity

以常用的多单元超导腔预调谐方法为基础,搭建了一套完整的预调谐系统,并实现了超导腔预调谐测量的自动化。实验首先通过网络分析仪对超导腔进行测量,利用Labview进行数据采集,并协同控制步进电机。通过"拉小珠"的微扰法,测量沿小珠运动路径的场分布。编写了一套Java程序,通过矩阵运算,计算出9单元腔各个腔单元频率的校正量。根据计算结果对9单元腔的某个单元进行挤压或拉抻,经多次上述操作后,在较高精度范围内,可将9单元铜腔的每个腔单元调谐至预期的目标频率。

A whole pretuning system was established and automatic measuring of the copper model of a 1.3 GHz 9-cell superconducting cavity was realized based on the commonly used theory of the tuning of multi-cell cavity＇s field flatness.For the bead pull measurement of the field profile,a Labview program was written to acquire data and control the step motor cooperatively.A Java program was written to calculate the frequency correction of each cell by a series of matrix manipulation of the field profile data.Then one of the 9 cells was squeezed or stretched according to the estimated frequency correction.With the procedure repeated for several times,the multi-cell cavity was tuned to the design frequency and field flatness with good accuracy.