激光与光电子学进展, 2014, 51 (7): 073401, 网络出版: 2014-06-24
高分辨宽能段软X射线光束线热负载影响与修正 下载: 534次
Analysis and Correction of Heating Effect on High Resolution and Wide Range Soft X-Ray Beamline
X射线光学 热形变修正 面形误差 有限元分析 光束线追迹 X-ray optics thermal deformation correction slope error finite element analysis ray tracing
摘要
正在建设中的上海光源梦之线(Dreamline)是一条宽能段、超高能量分辨率的软X 射线光束线。如此高指标的光束线在建设过程中有许多难点需要克服,其中光学元件的热变形是达到数万分辨能力的主要障碍。梦之线采用的5 m 长的波荡器会产生很高的热辐射从而使各光学元件,特别是第一块平面镜(M1)和第二块平面镜(M2)发生热形变进而影响整个光束线的性能。因此本文计算了Dreamline 各光学元件的热功率密度分布,在此基础上对各光学元件进行了稳态热分析,得到M1、M2 达到热平衡时的温度,热变形和面形误差分布,进而利用热变形结果对光束线进行了追迹,并且设计了一套热修正装置指导单色仪自身的聚集调节从而消除镜面热变形对光束线性能的影响。结果表明,即使在镜面热变形最高的情况下,通过对各光学元件进行有效的冷却并通过单色仪自身的聚集调节能消除镜面热形变对光束线性能的影响。
Abstract
The under building Dreamline at Shanghai Synchrotron Radiation Facility (SSRF) is a wide range and high resolution soft X-ray beamline. There are many difficulties to overcome for building a beamline with such high target. Especially, the thermal deformation of optical elements is one of the main obstacles. Based on the focal parameters of SSRF, the thermal power density distribution absorbed by optical elements is calculated. Finite element analysis is utilized to perform the thermo-mechanical analysis of M1 and M2 to obtain the temperature gradient distribution, the surface displacements and the slope errors of these optical elements, and then ray tracing simulation is done. In addition, a thermal deformation correction device is designed to cancel the deleterious effects of these deformations. According to the result, even under the worst-case thermal deformation of the optical element surfaces, effective cooling and appropriate focusing corrections are able to cancel the deleterious effects of these deformation.
石应波, 王勇, 邰仁忠, 丁洪. 高分辨宽能段软X射线光束线热负载影响与修正[J]. 激光与光电子学进展, 2014, 51(7): 073401. Shi Yingbo, Wang Yong, Tai Renzhong, Ding Hong. Analysis and Correction of Heating Effect on High Resolution and Wide Range Soft X-Ray Beamline[J]. Laser & Optoelectronics Progress, 2014, 51(7): 073401.