The deterioration of both the signal‐to‐noise ratio and the spatial resolution in the electron‐density distribution reconstructed from diffraction intensities collected at different orientations of a sample is analysed theoretically with respect to the radiation damage to the sample and the variations in the X‐ray intensities illuminating different copies of the sample. The simple analytical expressions and numerical estimates obtained for models of radiation damage and incident X‐ray pulses may be helpful in planning X‐ray free‐electron laser (XFEL) imaging experiments and in analysis of experimental data. This approach to the analysis of partially coherent X‐ray imaging configurations can potentially be used for analysis of other forms of imaging where the temporal behaviour of the sample and the incident intensity during exposure may affect the inverse problem of sample reconstruction.

中文翻译：

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X射线自由电子激光单粒子成像中辐射损伤和照度变化对信噪比的影响

从样品的不同方向收集的衍射强度重建的电子密度分布中的信噪比和空间分辨率的恶化都从理论上分析了样品的辐射损伤和X的变化射线强度照亮了样品的不同副本。对于辐射损伤和入射X射线脉冲模型获得的简单分析表达式和数值估计，可能有助于计划X射线自由电子激光（XFEL）成像实验和分析实验数据。