等效电路模型在漂移管直线加速器场稳定性调制中的应用

漂移管直线加速器(DTL)通过采用杆耦合器加速结构,实现加速电场的稳定性。为了分析电场稳定性的调制机理,简要说明DTL的腔体结构,并对其进行集总参数的等效模拟,给出等效电路分布。最后着重对耦合杆与漂移管之间相互作用的等效电容进行了仿真研究。针对上述电路分布,采用电路理论分析了高频场扰动及稳定性的实现机理。通过将稳定结构下的等效电容求解结果与该电容的模拟仿真值进行比较,得出稳定状态下的耦合杆与漂移管之间间隙取值的合理区间。最后通过对不同调节条件下的扰动电场进行仿真分析,一定程度上验证了结论的正确性。

Equivalent circuit model for stability modulation in Drift Tube Linac

Drift tube linac (DTL) uses the post coupler structure to achieve field stability. In order to explain the mechanism of stability modulation, we explained the structure of the DTL, then, we used the equivalent circuit model to analyse the structure and listed the circuit diagram. At last, we paid attention to the equivalent capacitance which represents the effect between post coupler and drift tube, and made its simulation. The circuit model was used to analyse the disturbed field and provide an explanation of post coupler stabilization. Through comparing the post coupler capacitances from simulation and circuit model, we got the reasonable width of the gap between post coupler and drift tube. Finally, we simulated the disturbed field under different conditions and the circuit theory was confirmed.