Compensation and improvement for bunch length diagnostics based on RF-phasing techniques-猫眼课题宝

基于射频定相技术的束长度诊断的补偿和改进

DOI：

10.1016/j.nima.2021.165583

发表时间：

2021-09

期刊：

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment

影响因子：

通讯作者：

中科院分区：

其他

文献类型：

作者：

Tongning Hu;Bingqian Zeng;Guangyao Feng;Yuanji Pei;Junyang Li;Jun Yang

电子束束团长度的可靠测量是高亮度束流注入器研制成功的关键。与通常涉及复杂技术和专用器件的方案相比，射频相移技术由于其方便和低成本而在低能量注入器中具有优势。虽然以往基于射频相移技术的直接计算公式在低能量注入器中是可行和有效的，但在实际操作中不可避免地存在不可忽略的误差，从而限制了其应用。通过回顾解析推导过程，重新考虑近似条件，通过理论分析和数值仿真，探索了补偿方法。使用束流动力学计算的虚拟测量来评估可靠性，并在华中科技大学注入器上进行了实验验证以验证补偿。这两项工作表明，在通常工作条件下的典型低能量注入器中，基于RF相移的束团长度诊断方法的改进是可行和可靠的。有了补偿，这些诊断方法是传统方法的一种有希望的替代。对于束流注入器，可能需要在紧凑的布局、低成本和完整的表征功能之间进行权衡。

Reliable bunch length measurement for electron beams is critical for the successful development of high-brightness beam injectors . Compared with commonly used schemes involving complicated techniques and dedicated devices, RF-phasing techniques have advantages in low-energy injectors owing to their convenience and low cost. Although previous direct calculation formulas originating from RF-phasing techniques are feasible and efficient in low-energy injectors, non-negligible errors are inevitable in practical operations, which limits application. By recalling the analytical derivation procedure and reconsidering the approximate conditions, compensation methods were explored through theoretical analysis and numerical simulations. Virtual measurements using beam dynamics calculations were used to evaluate reliability, and experimental validations were conducted at the HUST (Huazhong University of Science and Technology) injector to verify the compensation. Both of these efforts demonstrate that the improvements in the RF-phasing-based diagnostics for bunch length are feasible and reliable in typical low-energy injectors in common operating conditions. With compensation, these diagnostic methods are a promising alternative to conventional methods. For beam injectors, there may be a tradeoff among a compact layout, low cost, and complete characterization functions.