Theoretical Nuclear Physics

在这个项目中，将开发理论模型，以了解核物理的最新进展和发现，并预测可能的新发现。对于质子和中子数相差很大的核在当前加速器和计划中的稀有同位素束设施(FRIB)上的碰撞，基于相对论平均场模型的相对论输运模型将被扩展到包括真实的初始核分布和质子和中子的不同平均场势，然后通过双核子关联函数、轻核团的产生、质子和中子之间的相对扩散以及各种粒子的比率来研究核物质的能量对其密度和质子/中子比的依赖关系。对于相对论重离子对撞机(RHIC)和大型强子对撞机(LHC)上的超相对论重离子碰撞，碰撞产生的强胶子场和夸克和胶子的准粒子性质将被纳入多相输运模型，该模型既包括夸克和胶子之间的初始相互作用，也包括普通强子之间的最终相互作用，以及这两种物质之间的跃迁。由此产生的综合模型将被用来研究夸克-胶子等离子体的特征和性质，通过产生的粒子的集体动力学，碰撞过程中的电磁辐射，由重夸克组成的粒子的丰度，以及初始硬碰撞产生的非常高能量粒子的能量损失。对于托马斯·杰斐逊国家实验室(JLAB)由光子引发的核反应，将使用有效的强子模型来研究已知和缺失的重子共振的产生机制和性质。该项目具有学术价值，不仅直接影响美国三大核物理设施FRIB、RHIC和JLAB的研究计划，而且有助于理解天文和粒子物理中的许多重要问题。它还具有更广泛的影响，为参与的年轻学生和博士后研究人员提供广泛的研究经验，为他们在核科学或其他领域的职业生涯做好准备，继续为我们社会的科学和技术进步做出贡献。

In this project, theoretical models will be developed to understand recent advances and discoveries in nuclear physics and to predict possible new ones. For collisions of nuclei with very different proton and neutron numbers at current accelerators and planned Facility for Rare Isotope Beams (FRIB), the relativistic transport model based on the relativistic mean-field model will be extended to include realistic initial nuclear distributions and different mean-field potentials for protons and neutrons, and then used to study the dependence of the energy of nuclear matter on its density and proton to neutron ratio via the two-nucleon correlation functions, the production of light nuclear clusters, the relative diffusion between protons and neutrons, and the ratios of various particles. For ultrarelativistic heavy-ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC), the strong gluon fields generated in the collisions and the quasi-particle nature of the quarks and gluons will be incorporated in the multiphase transport model that includes both initial interactions among quarks and gluons and final interactions among ordinary hadrons as well as the transition between these two phases of matters. The resulting comprehensive model will be used to study the signatures and properties of the quark-gluon plasma through the collective dynamics of produced particles, the electromagnetic radiations during the collisions, the abundance of particles that consist of heavy quarks, and the energy loss of very energetic particles produced from initial hard collisions. For nuclear reactions induced by photons at the Thomas Jefferson National Laboratory (JLAB), effective hadronic models will be used to study the production mechanism and properties of both known and missing baryon resonances. The project has the intellectual merit of not only impacting directly the research programs at the three major nuclear physics facilities FRIB, RHIC, and JLAB in the U.S. but also contributing to the understanding of many important issues in astro- and particle physics. It also has the broader impact of providing participating young students and postdoctoral researchers a broad research experience that would prepare them well for careers in either nuclear science or other areas to continue their contributions to the scientific and technological advance in our society.