With low-emittance synchrotron radiation rings, introducing accurate x-ray beams to a sample is difficult, and ensuring that the direction of the undulator beam is stable is essential. However, measuring the centroid of the undulator photon beam at the beamline front-end (FE) is difficult because the soft x-ray radiation is contaminated by the bending magnets upstream and downstream of the undulator. The x-ray beam position monitors (XBPMs), based on the interaction with the halo of undulator radiation, cannot estimate the centroid of the beam, and they cannot eliminate the effects of the bending magnets. To solve this problem, we have developed an energy-resolved beam-monitoring system for undulator radiation with the scattering from a diamond thin film deposited by chemical vapor deposition (CVD) in this study. An undulator x-ray beam is irradiated onto this film, and its elastic and Compton scattering are observed through a 50 μm-diameter pinhole. A beam spot is detected through a pinhole camera system using a direct-detection-type charge-coupled device camera with energy resolution. The peak of the first-order harmonic of the undulator radiation is selectively visualized to measure the centroid of the undulator radiation, as well as the spectrum. The proposed system using a CVD diamond film can provide accurate position information for a photon beam exiting the FE.

中文翻译：

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使用化学气相沉积金刚石薄膜散射的波荡器辐射能量分辨光束监测系统

使用低发射同步辐射环，将准确的 X 射线束引入样品很困难，确保波束的方向稳定至关重要。然而，在光束线前端 (FE) 测量波动器光子束的质心是困难的，因为软 X 射线辐射被波动器上游和下游的弯曲磁铁污染。X 射线束位置监测器 (XBPM) 基于与波荡器辐射光环的相互作用，无法估计束的质心，也无法消除弯曲磁铁的影响。为了解决这个问题，我们开发了一种能量分辨光束监测系统，用于波动器辐射，在本研究中通过化学气相沉积 (CVD) 沉积的金刚石薄膜进行散射。波荡器 X 射线束照射到该薄膜上，通过 50 μm 直径的针孔观察其弹性和康普顿散射。使用具有能量分辨率的直接检测型电荷耦合器件相机，通过针孔相机系统检测束斑。波荡器辐射的一阶谐波的峰值被选择性地可视化，以测量波荡器辐射的质心以及光谱。所提出的使用 CVD 金刚石薄膜的系统可以为离开 FE 的光子束提供准确的位置信息。波荡器辐射的一阶谐波的峰值被选择性地可视化，以测量波荡器辐射的质心以及光谱。所提出的使用 CVD 金刚石薄膜的系统可以为离开 FE 的光子束提供准确的位置信息。波荡器辐射的一阶谐波的峰值被选择性地可视化，以测量波荡器辐射的质心以及光谱。所提出的使用 CVD 金刚石薄膜的系统可以为离开 FE 的光子束提供准确的位置信息。