Barrier Bucket双环双频模式下的高精度踢轨控制系统关键技术研究

A kicker system plays an important role in synchrotron beam extraction and injection between storage rings. The major projects of national “12th five-year plan” – HIAF(High Intensity Heavy-ion Accelerator Facility) will be the first time in China using Barrier Bucket longitudinal stacking to achieve high gain stacked and high intensity heavy ion beam. The Booster Ring (BRing) and Spectrometer Ring (SRing) with dual-ring and two-RF(Radio Frequency) structure propose new requirements to kicker control system. The currently used kicker control system in HIRFL (Heavy Ion Research Facility in Lanzhou) cannot meet the requirement of the fast extraction and injection under the dual-ring and two-RF mode. For the pre-research of HIAF and based on the completed Joint Funds of the National Natural Science Foundation of China (U1232123), our research group continue to submit “The key technology research of high precision kicker control system under the Barrier Bucket dual-ring and two-RF mode”. It is the extension and development of critical technology research on kicker control system. We will imitate beam fast extraction and injection approach on HIAF by making the necessary reform on HIRFL CSRe (experiment ring) and design a new kicker controller, so as to master the key technologies of kicker control under dual-ring and two-RF mode. The beam bunch position will be captured by relying on each of ring’s RF sweeping signal, then the Kicker trigger signals will be synchronously submitted to kicker power supplies according to the two captured beam phases. We intend to design a new kicker controller with ARM Cortex(1GHz) + FPGA(1GHz) architecture to achieve precise phase capturing (timing accuracy ≤1.0 ns) and signal delay, at the same time to overcome the strong electromagnetic interference to provide a stable trigger signal for beam diagnostic system and physics experiments. The expected beam current intensity in HIRFL CSRe can be increased 3 times after using Barrier Bucket method. It will provide reliable technical support and experience for HIAF project construction too.

用于存储环间束流传输的踢轨控制系统是同步加速器的重要组成部分。 “十二五”重大项目HIAF将通过Barrier Bucket纵向堆积来实现强流重离子束流的高增益堆积，其BRing和SRing的双环双频系统对踢轨控制提出了新要求，HIRFL现有的踢轨控制系统无法满足该要求。针对HIAF项目预研在已完成基金基础上提出本申请，它是踢轨控制关键技术研究的延续和发展，通过对HIRFL-CSRe进行必要的改造，可在HIRFL上模拟HIAF快引出/注入，从而掌握双环双频踢轨的关键技术。通过双环高频扫频相位信号扑捉束团位置并确定踢轨时刻。拟采用高速ARM Cortex和高性能FPGA芯片技术实现束流相位的精确扑捉(时间精度≤1.0 ns)和延迟，并克服强电磁干扰为束诊系统和物理实验提供稳定的触发信号，预期在HIRFL-CSRe中的束流传输效率提高3倍左右，为HIAF装置的建设提供可靠的技术保障和经验积累。

“Barrier Bucket双环双频模式下的高精度踢轨控制系统关键技术研究"通过细致的调研与讨论，制定了明确的研究计划，先后经过两次改版设计，研制成功了以ARM+FPGA为核心的单板结构的BB-KICK全数字化时序控制和延时调节器，时间延迟调节分辨达到了1.0ns，双环双频符合精度达到了1.0ns，相位符合精度达到了±1º。经过试验验证，结果表明满足了双环双频模式下踢轨控制系统的总体需求。在ARM-A9嵌入式平台上移植了thttpd web服务器，并成功运行了与底层驱动程序配合起来的CGI程序。培养了一名博士研究生和两名硕士研究生，在国际刊物上发表1篇SCI文章，4篇EI文章，国内核心刊物上发表2篇。经过3年的努力，解决了Barrier Bucket双环双频模式下高精度和高效率的快注入引出的关键科学技术问题，实现了预期的研究目标，并为HIAF（强流重离子加速器装置）项目的建设储备了技术基础。这些成果的取得完全是在联合基金对本项目的经费支持下取得的，在此深表感谢。