AI 中文总结
本研究结合从头算NLEFT的A核子构型与蒙特卡洛格劳伯计算，分析¹²C及铍同位素的反应截面，发现其可反映核多体几何演化，为研究奇特α团簇结构提供新途径。
AI 中文摘要
反应截面σ_R被广泛用于推断物质半径，但其对径向单粒子分布之外的核结构的敏感性尚不甚明确。我们结合从从头算核格点有效场理论（NLEFT）采样的完整A核子构型，与逐事件蒙特卡洛格劳伯计算，从而保留NLEFT编码的多体关联。采用由测量得到的与能量和同位旋相关的总核子-核子截面确定的固定二元碰撞方案，计算同时再现了¹²C和⁹Be弹核轰击碳与氢的可用数据的整体量级与能量依赖性。在固定物质均方根半径和球平均单粒子径向密度的情况下，对角关联进行可控随机化，仅使¹²C的σ_R产生微弱变化，但使⁹Be+¹H的σ_R增加约10%。计算还再现了⁷,⁹⁻¹²Be across的测量趋势——上升-平台-陡升-下降，这一独特模式反映了沿同位素链团簇与晕结构的演化。这些结果表明，σ_R保留了对超出单一推断物质半径的固有多体几何的敏感性，为通过反应截面研究奇特α团簇几何结构与空间核子关联开辟了途径。
英文摘要
Reaction cross sections $σ_{\rm R}$ are widely used to infer matter radii, yet their sensitivity to nuclear structure beyond radial one-body distributions is less well understood. We combine complete $A$-body nucleon configurations sampled from \textit{ab initio} nuclear lattice effective field theory (NLEFT) with event-by-event Monte Carlo Glauber calculations, thereby retaining the many-body correlations encoded in NLEFT. Using a fixed binary-collision prescription determined by the measured energy- and isospin-dependent total nucleon-nucleon cross sections, the calculations capture the overall magnitudes and energy dependence simultaneously for the available data on $^{12}$C and $^{9}$Be projectiles on carbon and hydrogen. Controlled randomization of angular correlations at fixed matter root-mean-square radius and spherically averaged one-body radial density produces only a weak change in $σ_{\rm R}$ for $^{12}$C but approximately a $10\%$ increase for $^{9}\mathrm{Be}+{}^{1}\mathrm{H}$. The calculations also capture the measured rise--plateau--sharp-rise--reduction trend across $^{7,9\text{--}12}$Be, a distinctive pattern reflecting the evolution of cluster and halo structures along the isotopic chain. These results show that $σ_{\rm R}$ retains sensitivity to intrinsic many-body geometry beyond a single inferred matter radius, opening a route to studies of exotic $α$-cluster geometries and spatial nucleon correlations through reaction cross sections.
