α集团结构在相对论重离子碰撞中的效应  

α-clustering effects in relativistic heavy-ion collisions

作　　者：马余刚 张松[1,2] MA Yu-Gan;ZHANG Song(Department of Nuclear Science and Technology/lnstitute of Modern Physics,Fudan University,Shanghai 200433,China;Shanghai Research Center for Theoretical Nuclear Physics,NSFC,Shanghai 200433,China)

机构地区：[1]复旦大学核科学与技术系/现代物理研究所,上海200433 [2]国家自然科学基金委理论物理专款-上海核物理理论研究中心,上海200433

出　　处：《中国科学：物理学、力学、天文学》2024年第9期30-45,共16页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家自然科学基金(编号:11890710,11890714,12275054,12147101);国家重点基础研究发展计划(编号:2018YFE0104600)资助项目。

摘　　要：相对论重离子碰撞的主要物理目标是寻找夸克-胶子等离子体(QGP)物质状态,并研究其性质.在开展相对论重离子碰撞物理研究的数十年中,人们在实验和理论上提出了各类探针来探测QGP信号,并通过这些观测量研究QGP的性质,集体流是其中最重要的探针之一.相对论流体力学对集体流的描述表明,非对心碰撞区域形成的火球在向外膨胀过程中,动量空间逐渐呈现各向异性的分布,这一分布特性直接受到碰撞初态位置空间的影响.近些年,随着研究的深入,人们关注到了一些引人深思的问题,如对心碰撞中是否存在椭圆流的信号?原子核的初态形变对末态动量空间产生怎样的影响?特殊核结构是否在集体流等观测量中呈现可辨认的信号?针对这些问题,国际上已经开展了一些研究工作,而且部分的理论研究工作已催生了新的实验测量.据此,一方面有必要对这些研究历程进行梳理,供今后的研究参考.另一方面,有必要讨论通过相对论重离子碰撞研究核结构问题的可能性.本文以α集团结构为例,对上述研究进行一个回顾,并对高能核-核碰撞作为核结构研究的新途径进行探讨.The main physical goal of relativistic heavy-ion collisions is to search for quark-gluon plasma(QGP) and study its properties. Over decades of research in relativistic heavy-ion collision physics, experimental and theoretical studies have proposed numerous probes to detect QGP signals and study their properties using various observables [2, 3]. Among these probes, collective flow is important. The description of collective flow in relativistic hydrodynamics indicates that the momentum space of the fireball formed in the noncentral collision region gradually exhibits an anisotropic distribution during its outward expansion, which is directly influenced by the coordinate space of the initial state of the colliding nuclei. In recent years, research has advanced, and attention is directed toward thought-provoking questions. For instance, researchers have explored whether an elliptical flow signal is present in head-on collisions. Additionally, they have investigated the influence of the initial deformation of atomic nuclei on the final momentum space. Moreover, there is interest in whether specific nuclear structures produce recognizable signals in observables such as collective flows. International studies have addressed these questions, and some theoretical studies have led to new experimental measurements. Therefore, summarizing the history is necessary for future research. Exploring the possibility of studying the nuclear structure problem through relativistic heavy-ion collisions is necessary. In this paper, we take the structure of the α-clusters inside atomic nuclei as an example to review the aforementioned studies and explore high-energy nucleus-nucleus collisions as a new approach to studying nuclear structure.

关 键 词：相对论重离子碰撞 夸克-胶子等离子体 集体流 椭圆流 三角流 α集团 

分 类 号：O571.6[理学—粒子物理与原子核物理]