Vibration of optics is one of the major limiting factors of the performance of state-of-the-art beamlines at low-emittance synchrotron facilities. We present a theoretical model with experimental data describing vibration-induced effects on x-ray beam coherence. Owing to the incoherent nature of vibration, the decrease in the beam spatial coherence perturbed by optics vibrations can be characterized by modeling the effective source profile of the vibrating beam. The measurements were carried out by using grating interferometry and a refractive lens with controlled vibration as test optics. The experimental results confirm the model and reveal the dependency of the measured beam spatial coherence on the acquisition time. The proposed method can be used to identify the eigenfrequency of the optical system as well as to optimize beamline operation and experimental conditions for coherence-related techniques.

中文翻译：

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光学振动对同步加速器光束相干性的影响

光学振动是低辐射同步加速器设备中最新光束线性能的主要限制因素之一。我们用实验数据介绍了一个理论模型，该数据描述了振动引起的X射线束相干效应。由于振动的非相干特性，可以通过对振动光束的有效源轮廓进行建模来表征由光学振动引起的光束空间相干性的降低。通过使用光栅干涉仪和具有受控振动的折射透镜作为测试光学器件进行测量。实验结果证实了该模型，并揭示了所测量的光束空间相干性对采集时间的依赖性。