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

这个项目一方面利用核物理和中微子物理学令人兴奋的新发展，另一方面利用日益复杂的天体物理和天文探测器、核合成历史和宇宙学，来探索中微子和原子核的基本物理学。该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中微子改变其味道。为此，UCSD的工作将致力于：(1)建立和理解控制一般介质中中微子味道演化的量子动力学方程；(2)建立各种超新星、恒星坍塌和致密天体合并环境中中微子味道演化的大规模数值模拟，并评估这种中微子味道物理对这些地点核合成前景的反馈；(3)了解中微子-核相互作用、核分配函数和高温环境中的弱强度分布；以及(4)评估中微子领域的不确定性和新的超标准模型可能性如何影响核合成、暗物质、致密物体物理和宇宙学的想法，以期找到实验室无法获得的约束条件。该项目支持的研究将为原子核和辐射在极端温度和密度条件下的行为提供见解。反过来，这些洞察力可能会为一些基本粒子的性质和元素的起源提供重要线索，例如，在超新星爆炸的火热内部，或者在宇宙只有几秒钟大的时候。这些都是根本性的问题，将为培养年轻科学家、核物理学家提供独特的机会，包括研究生和本科生。

This project probes 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, and the increasingly sophisticated astrophysical and astronomical probes of compact objects, nucleosynthesis histories, and 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 neutrinos to change their flavors. To these ends, this UCSD effort will work toward: (1) Formulating and understanding the quantum kinetic equations which govern neutrino flavor evolution in a general medium; (2) Constructing large-scale numerical simulations of neutrino flavor evolution in various supernova, stellar collapse, and compact object merger environments and assessing the feedback of this neutrino flavor physics on the prospects for the synthesis of nuclei in these sites; (3) Understanding neutrino-nucleus interactions, nuclear partition functions, and weak strength distributions in high temperature environments; and (4) Assessing how uncertainties and new beyond-standard-model possibilities in the neutrino sector could impact ideas on nucleosynthesis, dark matter, compact object physics, and cosmology, with an eye toward finding constraints otherwise unobtainable in the laboratory.The research supported in this project will provide insights into how atomic nuclei and radiation behave in extreme conditions of temperature and density. In turn, these insights could give important clues about the nature of some elementary particles and the origin of the elements, for example, in the fiery interiors of supernova explosions, or at the time when the universe was only seconds old. These are fundamental questions that will provide unique opportunities for the training of young scientists, nuclear physicists, at both the graduate and undergraduate levels.