There is a definite requirement of high vacuum degree in synchrotron accelerator. According to a study[1], the static LEAR vacuum pressure was about 510?12 Torr, but local pressure bumps up to 10?9 Torr occurred duri...There is a definite requirement of high vacuum degree in synchrotron accelerator. According to a study[1], the static LEAR vacuum pressure was about 510?12 Torr, but local pressure bumps up to 10?9 Torr occurred during continuous injection of about 108 ions/s. A dynamic pressure increase was attributed to the outgassing of vacuum equipment due to the impact of lost ions. The ion-induced desorption can seriously limit the ion intensity, luminosity, and beam lifetime of the accelerator.展开更多
The injecting section and the cooler section are apart from each other at CSRm, while the electron cooler systemis installed at the injecting section of CSRe[1]. So for the CSRe we not only need to satisfy the beam in...The injecting section and the cooler section are apart from each other at CSRm, while the electron cooler systemis installed at the injecting section of CSRe[1]. So for the CSRe we not only need to satisfy the beam injectingcondition but also need to satisfy the beam cooling condition. At present, we use the ramping bump and the kickerto inject beam, and after injection the bump disappear quickly and the beam goes to the cooling orbit and begincooling. This method has a disadvantage that the beam cooling condition cannot be satised until the bump isdown. In the past year, we try to nd a new method to correct the orbit of cooler section. Instead of using rampingbump we use the xed bump to satisfy the injecting and the cooling condition at the same time.展开更多
The electron cooler was installed in one of the straight sections of CSRe which is used to provide high-qualitybeams for experiments. Longitudinally the dynamics of the cooling process have been studied for a series o...The electron cooler was installed in one of the straight sections of CSRe which is used to provide high-qualitybeams for experiments. Longitudinally the dynamics of the cooling process have been studied for a series of electronbeam parameters and the friction force was measured with the aid of an RF-buncher for C6+ (122 MeV/u) and O8+(122 MeV/u) ions. The cooling time at different electron beam state have been measured, too.展开更多
中国科学院近代物理研究所在CSR-LINAC项目中设计了一台108.48 MHz的IH型RFQ直线加速器。该RFQ可以将质荷比为3~7的离子从4 ke V/u加速到300 ke V/u。在完成束流动力学设计的基础上,主要针对RFQ腔体的高频电磁设计展开了研究,同时利用...中国科学院近代物理研究所在CSR-LINAC项目中设计了一台108.48 MHz的IH型RFQ直线加速器。该RFQ可以将质荷比为3~7的离子从4 ke V/u加速到300 ke V/u。在完成束流动力学设计的基础上,主要针对RFQ腔体的高频电磁设计展开了研究,同时利用了电磁场仿真和束流动力学模拟来研究腔体的四极场不平整度和二极场及其动力学影响。未经调谐的情况下,腔体的谐振频率为108.15 MHz,腔体空载品质因子Q0为5 910,腔体功耗为123 k W。通过在支撑板两端增加底切的设计,将腔体的四极场不平整度由-21%~12%优化至±2.5%,满足了束流动力学要求。腔体的二极场为-3%~-2.2%,使得束流在垂直方向小幅振荡,RFQ的垂直方向接受度减小5%。为了保证功率馈入时反射较小,将耦合器设置在临界耦合状态,耦合面积为940 mm2。为了补偿腔体的频率偏差和漂移,设计了调谐量分别为707和132 k Hz的固定调谐器和可动调谐器。展开更多
文摘There is a definite requirement of high vacuum degree in synchrotron accelerator. According to a study[1], the static LEAR vacuum pressure was about 510?12 Torr, but local pressure bumps up to 10?9 Torr occurred during continuous injection of about 108 ions/s. A dynamic pressure increase was attributed to the outgassing of vacuum equipment due to the impact of lost ions. The ion-induced desorption can seriously limit the ion intensity, luminosity, and beam lifetime of the accelerator.
文摘The injecting section and the cooler section are apart from each other at CSRm, while the electron cooler systemis installed at the injecting section of CSRe[1]. So for the CSRe we not only need to satisfy the beam injectingcondition but also need to satisfy the beam cooling condition. At present, we use the ramping bump and the kickerto inject beam, and after injection the bump disappear quickly and the beam goes to the cooling orbit and begincooling. This method has a disadvantage that the beam cooling condition cannot be satised until the bump isdown. In the past year, we try to nd a new method to correct the orbit of cooler section. Instead of using rampingbump we use the xed bump to satisfy the injecting and the cooling condition at the same time.
文摘The electron cooler was installed in one of the straight sections of CSRe which is used to provide high-qualitybeams for experiments. Longitudinally the dynamics of the cooling process have been studied for a series of electronbeam parameters and the friction force was measured with the aid of an RF-buncher for C6+ (122 MeV/u) and O8+(122 MeV/u) ions. The cooling time at different electron beam state have been measured, too.
文摘中国科学院近代物理研究所在CSR-LINAC项目中设计了一台108.48 MHz的IH型RFQ直线加速器。该RFQ可以将质荷比为3~7的离子从4 ke V/u加速到300 ke V/u。在完成束流动力学设计的基础上,主要针对RFQ腔体的高频电磁设计展开了研究,同时利用了电磁场仿真和束流动力学模拟来研究腔体的四极场不平整度和二极场及其动力学影响。未经调谐的情况下,腔体的谐振频率为108.15 MHz,腔体空载品质因子Q0为5 910,腔体功耗为123 k W。通过在支撑板两端增加底切的设计,将腔体的四极场不平整度由-21%~12%优化至±2.5%,满足了束流动力学要求。腔体的二极场为-3%~-2.2%,使得束流在垂直方向小幅振荡,RFQ的垂直方向接受度减小5%。为了保证功率馈入时反射较小,将耦合器设置在临界耦合状态,耦合面积为940 mm2。为了补偿腔体的频率偏差和漂移,设计了调谐量分别为707和132 k Hz的固定调谐器和可动调谐器。