论文标题
一种在线动态振幅校正梯度估计技术，以使X射线焦点光学元件对齐
An Online Dynamic Amplitude-Correcting Gradient Estimation Technique to Align X-ray Focusing Optics
论文作者
论文摘要
在多种科学实验中使用了在同步性和X射线无电子激光器（XFEL）上产生的高亮度X射线脉冲。许多实验测试床需要光学设备，例如复合折射镜头（CRL），必须精确排列和聚焦。 CRL与光束线的横向对齐需要沿着四个轴进行精确定位：两个翻译和两个旋转。在同步加速器上，通常会手动完成对齐。但是，XFEL束线呈现出及时波动的光束亮度，使手动对齐成为耗时的努力。考虑到错误的梯度估计，使用经典随机方法的自动化通常会失败。我们根据广义有限差模型和时间相关的采样模式的组合提出了在线校正。分析了错误预期，并证明了功效。我们通过在模拟XFEL梁线上横向对准光学来提供概念证明。
High-brightness X-ray pulses, as generated at synchrotrons and X-ray free electron lasers (XFEL), are used in a variety of scientific experiments. Many experimental testbeds require optical equipment, e.g Compound Refractive Lenses (CRLs), to be precisely aligned and focused. The lateral alignment of CRLs to a beamline requires precise positioning along four axes: two translational, and the two rotational. At a synchrotron, alignment is often accomplished manually. However, XFEL beamlines present a beam brightness that fluctuates in time, making manual alignment a time-consuming endeavor. Automation using classic stochastic methods often fail, given the errant gradient estimates. We present an online correction based on the combination of a generalized finite difference stencil and a time-dependent sampling pattern. Error expectation is analyzed, and efficacy is demonstrated. We provide a proof of concept by laterally aligning optics on a simulated XFEL beamline.
