On Compton scattering as a source of background in coherent diffraction imaging experiments.
On Compton scattering as a source of background in coherent diffraction imaging experiments.
复制标题
康普顿散射作为相干衍射成像实验中的背景源。
DOI：
10.1107/s1600577521000722
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发表时间：
2021-03-01
影响因子：
2.5
通讯作者：
Carbone D
中科院分区：
文献类型：
--
作者：
Bikondoa O;Carbone D
分析了康普顿散射如何降低布拉格相干衍射成像技术的真实的空间分辨率。康普顿散射在衍射实验中通常被忽略，因为它产生的非相干辐射不会引起干涉效应，因此在布拉格峰处可以忽略不计。然而，随着散射体积的减小，布拉格峰处的瑞利（相干）和康普顿（非相干）贡献之间的差异减小，并且非相干部分可能变得很大。对于高散射角的相干衍射成像，其结果可能是显著的：非相干辐射产生背景，其涂抹掉二次干涉条纹，从而影响该技术可实现的分辨率。在这里，一个标准，涉及对象的形状和分辨率。几个对象的形状的康普顿贡献进行了量化，它示出了沿沿着不同方向的最大可实现的分辨率有很强的依赖于晶体的形状和大小。
How Compton scattering can reduce the real space resolution achievable with the Bragg coherent diffraction imaging technique is analysed. Compton scattering is generally neglected in diffraction experiments because the incoherent radiation it generates does not give rise to interference effects and therefore is negligible at Bragg peaks. However, as the scattering volume is reduced, the difference between the Rayleigh (coherent) and Compton (incoherent) contributions at Bragg peaks diminishes and the incoherent part may become substantial. The consequences can be significant for coherent diffraction imaging at high scattering angles: the incoherent radiation produces background that smears out the secondary interference fringes, affecting thus the achievable resolution of the technique. Here, a criterion that relates the object shape and the resolution is introduced. The Compton contribution for several object shapes is quantified, and it is shown that the maximum achievable resolution along different directions has a strong dependence on the crystal shape and size.