Impact of Stellar structure on Core-collapse Supernovae and their Ejecta

核心坍缩超新星（CCSN）是恒星演化的直接探针，也是重元素的主要生产者。在过去的十年中，我们对CCSN机制的理解取得了重大进展，突出表现在CCSN问题涉及许多物理输入的复杂相互作用，这些物理输入只能在三维（3D）模拟中充分考虑。已经完成的3D模拟（包括足够的真实物理）的数量仍然很少，并且模拟通常分辨率不足。最近的观测调查大大增加了观测良好的CCSN的数量，并确定了许多前超新星恒星，在爆炸的特征和细节之间建立更直接的关系。该项目将使用最先进的CCSN代码Chimera在Blue沃茨系统上调查CCSN祖先的恒星质量范围，以了解前超新星的结构会影响爆炸的结果。模拟将开始从祖先恒星，跨越恒星质量的范围，从最轻的到最重的恒星可能爆炸。祖先星星模型将来自大爆炸原始气体形成的第一代恒星，因为存在一类只被第一代超新星喷出物污染的第二代恒星，这为测量单个CCSN的喷出物提供了独特的机会。这一选择提供了一个重要的对比，以前的研究集中在富含金属的恒星。该项目将在2年内以1度分辨率计算5次3D模拟。该项目的更广泛影响包括当地和访问学生（研究生和本科生）和博士后的参与，为我们的学生和博士后提供天体物理学和高性能计算方面的培训，以便他们在学术界和工业界的未来工作中携带。 该项目还将经常就超新星相关主题进行公开讲座，以提高公众的理解。

Core-collapse supernovae (CCSN) are direct probes of stellar evolution and the dominant producers of heavy elements. Significant advancement in our understanding of the CCSN mechanism has occurred in the last decade, highlighted by the understanding that the CCSN problem involves the complex interaction of many physical inputs that can only be fully considered in three-dimensional (3D) simulations. The number of 3D simulations, which include sufficient realistic physics, that have been completed is still small and the simulations are generally under-resolved. Recent observational surveys have greatly increased the number of well observed CCSN and identified many of the pre-supernova stars, establishing a more direct relationship between the characteristics and the details of the explosion.This project will survey the range of the stellar mass of CCSN progenitors using the state-of-the-art CCSN code Chimera on the Blue Waters system to understand how the variations in pre-supernova structure affect the explosive outcomes. The simulations will begin from progenitor stars that span the range of stellar masses from the lightest to heaviest stars that might explode. The progenitor star models will be from the first generation of stars formed from the primordial gas of the Big Bang as there exists a class of second-generation stars contaminated by only the ejecta of first-generation supernovae that offer a unique opportunity to measure the ejected products of individual CCSN. This choice offers an important contrast to prior studies which have focused on metal-rich stars. The project will compute five 3D simulations over the course of 2 years with 1-degree resolution. This surpasses the resolution of any current self-consistent, full-physics CCSN simulation.The broader impacts of the project include the engagement of local and visiting students (graduate and undergraduate) and post-docs, providing training in both astrophysics and high-performance computing that our students and post-docs carry with them to later jobs in academia and industry. The project will also make frequent public lectures on supernova-related topics to enhance public understanding.