Title: Beam energy dependence of net-hyperon yield and its implication on baryon transport mechanism Show Chinese title

Title: 净超子产率的束流能量依赖性及其对重子输运机制的含义

Abstract: In the constituent quark model, each valence quark inside a baryon carries 1/3 unit of the baryon number. An alternative picture exists where the center of a Y-shaped topology of gluon fields, called the baryon junction, carries a unit baryon number. Studying baryon transport over a large rapidity gap ($\delta y$) in nuclear collisions provides a possible tool to distinguish these two pictures. A recent analysis of global data on net-proton yield at mid-rapidity in Au+Au collisions showed an exponential dependence on $\delta y$ and the exponential slope does not vary with event centrality, favoring the baryon junction picture. Since junctions are flavor blind, hyperons -- baryons containing valence strange quarks -- are expected to exhibit a similar behavior as the proton. This study aims to test this prediction by analyzing hyperon yields in Au+Au collisions at various energies. We observe that net-hyperon yields, after correcting for the strangeness production suppression, adhere to the expected exponential form. The extracted slope parameters for net-$\Lambda$, net-$\Xi$ and net-$\Omega$ are consistent with each other and with those of net-proton within uncertainties, and exhibit no centrality dependence, further substantiating the baryon junction picture. Various implementations of the PYTHIA event generator, primarily based on valence quarks for baryon transport, are unable to simultaneously describe the slope parameters for all baryons. Show Chinese abstract

Abstract: 在构成夸克模型中，重子内的每个价夸克携带1/3单位的重子数。 存在另一种图景，其中胶子场Y型拓扑结构的中心，称为重子结点，携带一个单位的重子数。 研究核碰撞中大快速度间隔（$\delta y$）上的重子输运提供了一种可能的工具来区分这两种图景。 对金-金碰撞中中间快速度处净质子产额的全球数据的最新分析显示，其与$\delta y$呈指数依赖关系，且指数斜率不随事件中心度变化，支持重子结点图景。 由于结点对味不敏感，超子——包含价奇异夸克的重子——预期会表现出与质子类似的行为。 本研究旨在通过分析不同能量下金-金碰撞中的超子产额来验证这一预测。 我们观察到，在对奇异生成抑制进行修正后，净超子产额符合预期的指数形式。 提取的净-$\Lambda$、净-$\Xi$和净-$\Omega$的斜率参数彼此一致，并且与净质子的参数在不确定范围内一致，且没有中心度依赖性，进一步证实了重子结点图景。 各种基于价夸克的PYTHIA事件生成器的实现无法同时描述所有重子的斜率参数。