合肥光源的新高频腔阻抗谱计算

Impedance spectrum calculation for the HLS new RF cavity

用电磁场计算软件MAFIA,在时域和频域两种情况下,对高频腔的耦合阻抗及电子束在此结构中产生的尾场进行了计算。结果表明,新高频腔里存在较强的高次模,需要采取措施加以抑制。

The phase II upgrading project of Hefei 800MeV electron storage ring is being carried out, and its new RF cavity will be finished. In high current operation mode the narrow band coupling impedance of RF cavity can cause different beam bunches to interact, so both longitudinal and transverse coupled modes will be excited. To estimate the effect of the RF cavity coupling impedance on stored bunch intensity fully, the long-range wakefield and the narrow band coupling impedance of RF cavity were calculated with MAFIA program. And the calculation results showed that there are some high order modes in the new RF cavity , which need to be damped.