New Directions in High Energy Nuclear Physics

在自然界的四种基本力中，强核力是人们最不了解的一种。它驱动着宇宙中对我们的存在至关重要的许多过程。强核力的一个特别重要的方面是夸克胶子等离子体的存在。如果普通物质被加热到大约10亿度的温度，比太阳的核心还要热，原子和分子就不再存在，甚至原子核内的质子和中子也会熔化。剩余的夸克和胶子的原始汤充满了非常早期的宇宙。我们可以在我们最大的粒子对撞机中通过重原子核的相互碰撞来重建夸克胶子等离子体。欧洲的大型强子对撞机和美国的相对论重离子对撞机的实验计划研究夸克胶子等离子体的性质。这个项目将支持研究，这将提高我们对核碰撞中夸克胶子等离子体的形成和性质的理解。PI和他的合作者将使用计算机模拟和先进的统计方法来实现这一目标。核碰撞中的夸克胶子等离子体产生于最初在核碰撞中产生的高度复杂的胶子场。PI和他的团队将通过研究夸克胶子等离子体液滴的角动量如何与碰撞核的初始角动量相关来研究这些场及其性质。同样的胶子场也将通过它们与快夸克的相互作用来研究。PI和他的团队将能够使用JETSCAPE框架进行核碰撞的大规模计算模拟。他们将研究喷流和重夸克在夸克胶子等离子体中被淬灭的各个方面。然后，他们将使用多个约束提取夸克胶子等离子体的属性。例如，夸克和重夸克的淬灭强度，夸克胶子等离子体的粘度可以独立测量，并且是相互关联的。检验这些关系将是深入了解夸克胶子等离子体动力学的重要一步。PI和他的团队还将使用先进的统计方法和应用于数据的机器学习来理解夸克和胶子形成强子的机制。这些结果将用于改进强子化过程的最先进建模，这是许多计算的关键输入。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

Among the four fundamental forces in nature the strong nuclear force stands out for being the least understood one. It drives many processes in the universe that are crucial for our existence. One particularly important aspect of the strong nuclear force is the existence of quark gluon plasma. If ordinary matter is heated up to temperatures of about 1,000,000,000,000 degrees, hotter than the core of the sun, atoms and molecules cease to exist and even protons and neutrons inside atomic nuclei melt. The remaining primordial soup of quarks and gluons filled the very early universe. We can recreate quark gluon plasma in our largest particle colliders by smashing heavy nuclei into each other. Experimental programs at the Large Hadron Collider in Europe and the Relativistic Heavy Ion Collider in the USA study the properties of quark gluon plasma. This project will support research that will improve our understanding of the formation and properties of quark gluon plasma in nuclear collisions. The PI and his collaborators will use computer simulations and advanced statistical methods to reach this goal. Funding is provided to support training for a graduate students and junior scientists in nuclear science.Quark gluon plasma in nuclear collisions emerges from the highly complex gluon fields that are initially created in nuclear collisions. The PI and his group will investigate these fields and their properties by studying how angular momentum of the droplets of quark gluon plasma is related to the initial angular momentum of the colliding nuclei. The same gluon fields will also be studied through their interaction with fast quarks. The PI and his group will be able to use the JETSCAPE framework for large scale computational simulations of nuclear collisions. They will study various aspects of jets and heavy quarks being quenched in quark gluon plasma. They will then extract properties of quark gluon plasma using multiple constraints. For example, the strength of quenching of quarks and heavy quarks, and the viscosity of quark gluon plasma can be independently measured and are mutually related. Testing these relations will be an important step towards a deeper understanding of the dynamics of quark gluon plasma. The PI and his group will also use advanced statistical methods and machine learning applied to data to understand the mechanisms of hadron formation from quarks and gluons. These results will be used to improve the state-of-the-art modeling of the hadronization process that is a crucial input to many calculations.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.