Quark Matter and its Role in the Evolution of Proton-Neutron Stars to Neutron Stars

星系中充满了数以亿计的紧凑的恒星物体，称为中子星。 中子星比我们的太阳质量更大，但通常只有大约20公里宽。因此，一个充满中子星星物质的顶针的质量为10亿吨。在这种特殊的条件下，原子核坍缩，中子和质子被紧紧地挤压在一起，甚至它们的积木（夸克）也可能被释放出来。 该项目的目的是研究夸克在新形成的中子星中的作用，并确定天体物理观测中可能的特征。研究生和本科生将在丰富的跨学科物理领域接受培训，并丰富他们在课堂上学到的教育经验。来自当地初中和高中的学生将受益于PI的公开讲座和多媒体演示形式的研究。这项研究将支持最先进的天体物理仪器，如FAST，skA，ATHENA和NICER的物理计划，这些仪器有望发现数万颗处于不同演化阶段的新中子星。这项提议的主要目的是研究原中子星特征条件下的夸克物质，用非定域3味Polyakov-Nambu-Jona-Lasinio（n3 PNJL）模型描述热而致密的夸克物质，探讨夸克物质在原中子星到中子星演化中的作用. n3 PNJL模型是一个有效的量子色动力学模型，它允许对夸克物质进行最先进的建模。 该模型考虑了手征对称性的动力学破缺，并通过Polyakov圈势模拟夸克禁闭。它为量子色动力学提供了一个通用的和数值可处理的方法。来自重离子碰撞和中子星星观测的最佳可用数据将用于约束（原）中子星星物质的状态方程，该方程将在CompOSE和StellarCollapse上进行计算并在线公开。 已经存在的，完全广义相对论数值二维旋转和二维冷却代码将被用来研究旋转演化的热原中子星冷催化中子星自洽。均匀旋转和微分旋转系统都将被考虑，并探讨它们作为引力辐射可能来源的作用。

Galaxies are filled with hundreds of millions of compact stellar objects known as neutron stars. Neutron stars are more massive than our Sun, but are typically only about 20 kilometers across. A thimble full of neutron star matter thus has a mass of one billion tons. At such extraordinary conditions, atomic nuclei collapse and neutrons and protons are squeezed so tightly together that even their building blocks (quarks) may be released. The aim of this project is to study the role of quarks for newly formed neutron stars and to identify possible signatures in astrophysical observables. Graduate and undergraduate students will be trained in areas of physics that are richly interdisciplinary and enrich their educational experience beyond what they learn in the classroom. Students from local middle and high schools will benefit from the PI's research in the form of public lectures and multimedia presentations. This research will support the physics program at state-of-the-art astrophysical instruments, such as FAST, skA, ATHENA, and NICER, that promise the discovery of tens of thousands of new neutron stars at different stages of their evolution.The principal aim of this proposal is to study quark matter under conditions characteristic to proto-neutron stars, using the non-local 3-flavor Polyakov-Nambu-Jona-Lasinio (n3PNJL) model to describe hot and dense quark matter, and to explore the role of quark matter in the evolution of proto-neutron stars to neutron stars. The n3PNJL model is an effective model of quantum chromodynamics that allows for a state-of-the-art modeling of quark matter. The model accounts for the dynamical breaking of chiral symmetry and mimics quark confinement via the Polyakov-loop potential. It provides a versatile and numerically-treatable approach to quantum chromodynamics. The best available data from heavy-ion collisions and neutron star observations will be used to constrain the equation of state of (proto-) neutron star matter, which will be computed and made publicly available online at CompOSE and StellarCollapse. Already existing, fully general relativistic numerical 2D rotation and 2D cooling codes will be used to study the rotational evolution of hot proto-neutron stars to cold catalyzed neutron stars self-consistently. Both uniformly-rotating as well as differentially-rotating systems will be considered and their role as possible sources of gravitational radiation explored.