Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Bldg. 436D, Argonne, IL 60439, USA.
Life Sciences Institute, University of Michigan, 210 Washtenaw Avenue, Ann Arbor, MI 48109, USA.
J Synchrotron Radiat. 2022 Mar 1;29(Pt 2):393-399. doi: 10.1107/S1600577522001084. Epub 2022 Feb 15.
Algorithms and procedures to fully automate retuning of synchrotron radiation beamlines over wide energy ranges are discussed. The discussion is based on the implementation at the National Institute of General Medical Sciences and the National Cancer Institute Structural Biology Facility at the Advanced Photon Source. When a user selects a new beamline energy, software synchronously controls the beamline monochromator and undulator to maintain the X-ray beam flux after the monochromator, preserves beam attenuation by determining a new set of attenuator foils, changes, as needed, mirror reflecting stripes and the undulator harmonic, preserves beam focal distance of compound refractive lens focusing by changing the In/Out combination of lenses in the transfocator, and, finally, restores beam position at the sample by on-the-fly scanning of either the Kirkpatrick-Baez mirror angles or the transfocator up/down and inboard/outboard positions. The sample is protected from radiation damage by automatically moving it out of the beam during the energy change and optimization.
讨论了在宽能区范围内全自动重新调整同步加速器辐射光束线的算法和程序。该讨论基于在国家普通医学科学研究所和高级光源结构生物学设施的国家癌症研究所的实现。当用户选择新的光束线能量时，软件会同步控制光束线单色仪和波荡器，以在单色仪之后保持 X 射线光束通量，通过确定一组新的衰减箔来保持光束衰减，根据需要改变镜反射带和波荡器谐波，通过改变变焦距器中的透镜的内/外组合来保持复合折射透镜聚焦的光束焦距，最后，通过 Kirkpatrick-Baez 镜角度或变焦距器的上下、内外位置的实时扫描，恢复样品处的光束位置。通过在能量变化和优化过程中自动将样品移出光束，保护样品免受辐射损伤。
