Monochromatic X-ray-induced thermal effect on four-reflection“nested” me V-monochromators: dynamical diffraction theory and finite-element analysis  

作　　者：胡凌飞 高立丹 李贞杰 王山峰 盛伟繁 刘鹏 徐伟 

机构地区：[1]BSRF, Institute of High Energy Physics, Chinese Academy of Sciences

出　　处：《Chinese Physics C》2015年第9期83-89,共7页中国物理C（英文版）

摘　　要：The high energy resolution monochromator （HRM） is widely used in inelastic scattering programs to detect phonons with energy resolution, down to the meV level. Although the large amount of heat from insertion devices can be reduced by a high heat-load monochromator, the unbalanced heat load on the inner pair of crystals in a nested HRM can affect its overall performance. Here, a theoretical analysis of the unbalanced heat load using dynamical diffraction theory and finite element analysis is presented. By utilizing the ray-tracing method, the performance of different HRM nesting configurations is simulated. It is suggested that the heat balance ratio, energy resolution, and overall spectral transmission efficiency are the figures of merit for evaluating the performance of nested HRMs. Although the present study is mainly focused on nested HRMs working at 57Fe nuclear resonant energy at 14.4 keV, it is feasible to extend this to other nested HRMs working at different energies.The high energy resolution monochromator （HRM） is widely used in inelastic scattering programs to detect phonons with energy resolution, down to the meV level. Although the large amount of heat from insertion devices can be reduced by a high heat-load monochromator, the unbalanced heat load on the inner pair of crystals in a nested HRM can affect its overall performance. Here, a theoretical analysis of the unbalanced heat load using dynamical diffraction theory and finite element analysis is presented. By utilizing the ray-tracing method, the performance of different HRM nesting configurations is simulated. It is suggested that the heat balance ratio, energy resolution, and overall spectral transmission efficiency are the figures of merit for evaluating the performance of nested HRMs. Although the present study is mainly focused on nested HRMs working at 57Fe nuclear resonant energy at 14.4 keV, it is feasible to extend this to other nested HRMs working at different energies.

关 键 词：dynamical diffraction theory high energy resolution monochromator heat load 

分 类 号：O434.1[机械工程—光学工程]