Nuclear, Particle, and Weak Interaction Physics of the Big Bang and Stellar Collapse

该项目支持的研究将深入了解原子核、基本粒子和辐射在宇宙中极端温度和密度条件下的行为。这项研究将寻求利用这些见解，为基本粒子的本质提供重要线索，特别是神秘的中微子，以及这些元素在自然界是如何合成的，例如，坍缩恒星或碰撞中子星炽热内部最重的元素，以及宇宙历史上最初几秒钟最轻的元素。反过来，这些考虑可能会产生关于新物理学的线索，这些线索可能会补充从地面实验中收集到的见解。在这个项目中进行的计算将涉及将人类关于自然的基本理论，即量子力学，打磨成一种能够模拟宇宙极端环境中中微子和原子核行为的工具。这个项目的另一个关键产品将是在研究生和本科两级培训年轻的核物理学家。本项目支持的研究将通过利用核物理学和中微子物理学令人兴奋的新发展的交叉点，以及多信使天文学和精确宇宙学的出现带来的新数据和见解的爆炸式增长，直接探索中微子和原子核的基本物理。这个项目的一个关键问题将是研究中微子如何在致密物质中相互作用，以及这些相互作用如何导致这些粒子改变它们的口味（例如，电子型中微子变成tau型，反之亦然）。这可能是一个严重的非线性问题，因为中微子成分的风味成分在一定程度上决定了中微子风味的变化！本项目的研究目标是(1)理解和模拟非线性中微子风味演化，并评估这一过程对致密物体（坍缩恒星核心；合并双中子星）动力学和核合成的影响；(2)利用这些和其他考虑的见解，将我们对致密物体环境和早期宇宙的模型和观测约束转化为超越标准模型物理学、暗物质和暗物质物理的见解；(3)了解核结构、中微子-核相互作用、核配分函数和高温环境下的核弱强度分布。该项目推进了“宇宙之窗：多信使天体物理学时代”的目标，这是美国国家科学基金会未来投资的十大理念之一。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

The research supported in this Project will provide insights into how atomic nuclei and elementary particles and radiation behave in the conditions of extreme temperature and density found in the cosmos. This research will seek to use these insights to provide important clues about the nature of elementary particles, the mysterious neutrinos in particular, and about how the elements are synthesized in nature, for example, the heaviest elements in the fiery interiors of collapsing stars or colliding neutron stars, and the lightest in the first seconds in the history of the universe. In turn, these considerations could yield clues about new physics, clues that may complement insights gleaned from terrestrial experiments. The calculations to be done in this project will involve honing humanity's fundamental theory of nature, i.e., Quantum Mechanics, into a tool capable of modeling the behavior of neutrinos and atomic nuclei in the extreme environments of the cosmos. Another key product of this Project will be the training of young nuclear physicists, at both the graduate and undergraduate levels. The research supported in this Project will be directed toward probing the fundamental physics of neutrinos and nuclei by exploiting the intersection of exciting new developments in nuclear physics and neutrino physics on the one hand, with the explosion of new data and insights from the advent of multi-messenger astronomy and precision cosmology on the other. A key issue in this enterprise will be studying how neutrinos interact in dense matter and how these interactions may cause these particles to change their flavors (e.g., electron type neutrinos changing to tau type and vice versa). This can be a fiercely nonlinear problem because the flavor content of the neutrino component in part determines how neutrino flavors change! Research in this project will target (1) Understanding and modeling nonlinear neutrino flavor evolution and assessing the impact of this process on compact objects (collapsing stellar cores; merging binary neutron stars) dynamics and nucleosynthesis; (2) Using the insights from these and other considerations to turn our models of, and observational constraints on compact object environments and the early universe into insights into beyond standard model physics, dark matter, and dark sector physics; (3) Understanding nuclear structure, neutrino-nucleus interactions, nuclear partition functions, and nuclear weak strength distributions in high temperature environments.This project advances the objectives of "Windows on the Universe: the Era of Multi-Messenger Astrophysics", one of the 10 Big Ideas for Future NSF Investments.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.