Momentum bandwidth is an important characteristic for final focus systems (FFS) of future high-energy colliders. A large momentum bandwidth is a notable feature of the novel local-chromaticity-correction FFS, being demonstrated at the KEK Accelerator Test Facility 2 (ATF2), owing to the locality of chromaticity correction. In this article, analytical estimations and simulations of momentum bandwidth for various optics of ATF2 are presented. Possible deviations of the momentum bandwidth due to realistic machine imperfections are studied. Experimental measurements at ATF2 following successful tuning of small vertical beam size at the interaction point (IP) are also described, which agree well with numerical predictions and further verify the robustness of the local chromaticity correction scheme.

中文翻译：

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KEK加速器测试设施2的动量带宽

动量带宽是未来高能对撞机的最终聚焦系统（FFS）的重要特征。大的动量带宽是新颖的局部色度校正FFS的显着特征，由于色度校正的局部性，因此在KEK加速器测试设施2（ATF2）上得到了证明。本文介绍了ATF2各种光学器件的动量带宽的分析估计和仿真。研究了由于实际的机器缺陷而引起的动量带宽的可能偏差。还介绍了在成功调整相互作用点（IP）处的小垂直光束大小后在ATF2进行的实验测量结果，这些结果与数值预测非常吻合，并进一步验证了局部色度校正方案的鲁棒性。