粒子束团状态对测量束流发射度及能量的影响

为了验证国产质子注入器的参数是否满足需求，注入器团队设计了束流测量系统用于测量国产质子直线注入器束流的流强、发射度、能量以及能散等关键指标。此测量系统包含了采用变聚焦法测量发散度、采用分析磁铁测量束流能量和能散的主要功能。利用束流输运线设计软件Tracewin(版本2.11.4.1)进行了系统束线的物理设计，对束测系统测量质子束流的发散度和能量的精度进行了模拟计算。由于经过RFQ-(APF)DTL加速后的粒子束团为“拖尾”的非理想粒子束团，需要针对非理想束团对束测系统测量发射度和能量产生的影响进行分析。通过对模拟计算结果的分析，发现相对于测量理想粒子束团的结果非理想粒子束团对束测系统测量发射度精度影响较大；非理想粒子束团对束测系统测量能量精度影响较小。

Effects of bunch state on measurement of beam emittance and energy

To verify whether the parameters of the domestic proton injector meet the requirements, a beam diagnostic system was designed to measure the current, emittance, energy and energy spread of the domestic proton linear injector beam. This beam diagnostic system has the main functions of measuring the emittance by variable focus method and measuring beam energy and energy spread by analyzing magnet. The beam transport line design software Tracewin (version 2.11.4.1) was used to design the physical system beam line, and the accuracy of the beam diagnostic system to measure the emittance and energy of the proton beam was simulated and calculated. Since the beam accelerated by RFQ-(APF)DTL is a “trailing” non-ideal bunch , it is necessary to analyze the influence of the non-ideal bunch on the emittance and energy measurement of the beam diagnostic system. The analysis of the simulation calculation results shows that compared with the ideal bunch, the non-ideal bunch has greater impact on emittance measurement accuracy and smaller impact on energy measurement accuracy of the beam diagnostic system.