Singh Saransh, Coleman Amy L, Zhang Shuai, Coppari Federica, Gorman Martin G, Smith Raymond F, Eggert Jon H, Briggs Richard, Fratanduono Dayne E
Lawrence Livermore National Laboratory, Computational Engineering Division, Livermore, CA 94511, USA.
Laboratory for Laser Energetics, University of Rochester, Rochester, NY 14623, USA.
J Synchrotron Radiat. 2022 Jul 1;29(Pt 4):1033-1042. doi: 10.1107/S1600577522004076. Epub 2022 May 16.
A new approach for performing quantitative structure-factor analysis and density measurements of liquids using X-ray diffraction with a pink-spectrum X-ray source is described. The methodology corrects for the pink beam effect by performing a Taylor series expansion of the diffraction signal. The mean density, background scale factor, peak X-ray energy about which the expansion is performed, and the cutoff radius for density measurement are estimated using the derivative-free optimization scheme. The formalism is demonstrated for a simulated radial distribution function for tin. Finally, the proposed methodology is applied to experimental data on shock compressed tin recorded at the Dynamic Compression Sector at the Advanced Photon Source, with derived densities comparing favorably with other experimental results and the equations of state of tin.
描述了一种使用粉红光谱X射线源通过X射线衍射对液体进行定量结构因子分析和密度测量的新方法。该方法通过对衍射信号进行泰勒级数展开来校正粉红光束效应。使用无导数优化方案估计平均密度、背景比例因子、进行展开的峰值X射线能量以及密度测量的截止半径。该形式主义通过锡的模拟径向分布函数得到了证明。最后,将所提出的方法应用于在先进光子源动态压缩部门记录的冲击压缩锡的实验数据,推导得到的密度与其他实验结果以及锡的状态方程相比具有优势。