Particle knockout scattering experiments^1,2 are fundamental for mapping the structure of atomic nuclei^2,3,4,5,6, but their interpretation is often complicated by initial- and final-state interactions of the incoming and scattered particles^1,2,7,8,9. Such interactions lead to reduction in the scattered particle flux and distort their kinematics. Here we overcome this limitation by measuring the quasi-free scattering of 48 GeV c^{–1 12}C ions from hydrogen. The distribution of single protons is studied by detecting two protons at large angles in coincidence with an intact ¹¹B nucleus. The ¹¹B detection suppresses the otherwise large distortions of reconstructed single-proton distributions induced by initial- and final-state interactions. By further detecting residual ¹⁰B and ¹⁰Be nuclei, we also identified short-range correlated nucleon–nucleon pairs^{9,10,11,12,13} and provide direct experimental evidence for separation of the pair wavefunction from that of the residual many-body nuclear system^9,14. All measured reactions are well described by theoretical calculations that include no distortions from the initial- and final-state interactions. Our results showcase the ability to study the short-distance structure of short-lived radioactive nuclei at the forthcoming Facility for Antiproton and Ion Research (FAIR)¹⁵ and Facility for Rare Isotope Beams (FRIB)¹⁶ facilities, which is relevant for understanding the structure and properties of nuclei far from stability and the formation of visible matter in the Universe.

粒子敲除散射实验^1,2是绘制原子核结构^2,3,4,5,6的基础，但它们的解释通常因入射和散射粒子^{1,2 的初始状态和最终状态相互作用而变得复杂， 7,8,9}。这种相互作用导致散射粒子通量的减少并扭曲它们的运动学。在这里，我们通过测量来自氢的 48 GeV c ^{–1 12} C 离子的准自由散射来克服这一限制 。^{通过在与完整的11} B 核重合的大角度检测两个质子来研究单个质子的分布。¹¹ _B 检测抑制了由初始状态和最终状态相互作用引起的重建单质子分布的大失真。通过进一步检测剩余的¹⁰ B 和¹⁰ Be 核，我们还确定了短程相关的核子-核子对^{9、10、11、12、13}，并为分离对波函数与剩余多体波函数提供了直接的实验证据核系统^9,14。所有测量的反应都通过理论计算得到了很好的描述，其中不包括来自初始状态和最终状态相互作用的扭曲。我们的结果展示了在即将到来的反质子和离子研究设施 (FAIR) 研究短寿命放射性核的短距离结构的能力¹⁵和稀有同位素束设施 (FRIB) ¹⁶设施，这与了解远离稳定性的原子核的结构和性质以及宇宙中可见物质的形成有关。