螺旋型波荡器辐射特性及光束线前置镜热载分布

Synchrotron radiation characteristics of helical undulator and thermal distribution of premirror for beamline

对合肥国家同步辐射实验室(NSRL)引进、装备的螺旋型电磁波荡器进行了改造和性能研究,该螺旋型电磁波荡器被插入电子储存环的直线段,来产生高通量圆偏振相干光,提供一条真空紫外光束线,用于燃烧科学研究。基于NSRL改造后的光源参数,分析其同步辐射偏振特性,计算了该波荡器辐射出的总功率和功率密度分布,以及受其直接辐照的光束线前置环面镜的热载、温度场和由此导致的光学镜面面形误差。研究结果表明,在燃烧实验要求的光子能量范围内,聚焦镜在光束照射镜面内的热变形都不超过2μm,最大面形误差约为1μrad,能满足实验要求。

A helical undulator introduced by National Synchrotron Radiation Laboratory was reformed and its performance was researched.The helical undulator was installed at the linear part of a storage ring to produce coherent synchrotron radiation with high flux and circular polarization and to provide a VUV beamline.Based on improved source parameters,the polarization radiation characteristics of the helical undulator were analyzed and the power density distribution radiated by the helical undulator,thermal distortion and the slope error on the premirror surface were calculated with ANSYS.The results show that the maximal thermal distortion of the premirror is less than 2 μm in a photon energy range desired by a burning experiment and the maximal slope error is about 1 μrad.Obtained results satisfy the requirement of SR experiment very well.