The resonant interaction of a bunched particle beam with short-range wakefields is the cause of head-tail instability, which is a major limitation for single-bunch beam intensity in circular accelerators. There are several processes that suppress this type of instability, such as fast chromatic damping and Landau damping due to machine nonlinearity. Beam-based feedback systems (transverse dampers) provide active suppression of the beam oscillations. The combined effect of the transverse dampers and chromaticity is discussed in this article. A brief overview of theoretical and experimental studies of the head-tail instability and its mitigation is presented. Results of experimental studies of the transverse mode coupling carried out at National Synchrotron Light Source-II are compared with the theoretical model.

中文翻译：

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色度和反馈对横向头尾不稳定性的综合影响

束状粒子束与短程尾波场的共振相互作用是头尾不稳定的原因，这是圆形加速器中单束光束强度的主要限制。有多种方法可以抑制这种类型的不稳定性，例如由于机器非线性而导致的快速色度阻尼和Landau阻尼。基于波束的反馈系统（横向阻尼器）可主动抑制波束振荡。本文讨论了横向阻尼器和色度的综合作用。简要介绍了头尾不稳定性及其缓解方法的理论和实验研究。将国家同步加速器光源II进行的横模耦合实验研究的结果与理论模型进行了比较。