Single neutron- and proton-removal cross sections have been systematically measured for 72 medium-mass neutron-rich nuclei around Z=50 and energies around 900A MeV using the FRagment Separator (FRS) at GSI. Neutron-removal cross sections are described by considering the knock-out process together with initial- and final-state interactions. Proton-removal cross sections are, however, significantly smaller than predicted by the same calculations. The observed difference can be explained as due to the knockout of short-correlated protons in neutron-proton dominating pairs.

中文翻译：

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富中子中等质量原子核中质子去除截面的系统减少

已经使用 GSI 的碎片分离器 (FRS) 系统地测量了 72 个中等质量的富中子核在 Z=50 附近和能量在 900A MeV 左右的单个中子和质子去除截面。通过考虑敲除过程以及初始和最终状态相互作用来描述中子去除截面。然而，去除质子的横截面明显小于相同计算所预测的。观察到的差异可以解释为由于中子 - 质子主导对中短相关质子的敲除。