Collaborative Research: Electron Impact Ionization and Recombination Properties of Heavy elements in Kilonovae.

电子碰撞电离（EII）和双电子复合（DR）是控制天体物理等离子体电离平衡的关键过程。本研究计画将计算中子星星合并（NSMs）中产生的重元素的精确EII和DR截面。这些计算将使天文学家能够准确地解释kilonovae的光谱，这是NSM喷出的物质的瞬变电磁发射，从而推进我们对宇宙中最重元素生产地点的理解。该项目将培养一名高级原子物理学方法的研究生，为本科生提供研究机会，并使高中生接触天文学研究。使用现代电子结构代码，研究人员将计算和基准EII和DR截面的重要元素的离子产生的快速中子捕获过程中的NSM。广泛的计算将产生DR率系数的温度一致的热（低能量）和非热（高能量）的电子成分在kilonova喷出物。EII截面将允许研究人员探索从kilonova发射模型中缺失的其他电离机制的贡献。该项目推进了"宇宙大创意视窗“的目标。该奖项反映了NSF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。

Electron impact ionization (EII) and dielectronic recombination (DR) are key processes that govern the ionization balance of astrophysical plasmas. This research project will calculate accurate EII and DR cross sections for heavy elements produced in neutron star mergers (NSMs). These calculations will allow astronomers to accurately interpret the spectra of kilonovae, the transient electromagnetic emission from material ejected by NSMs, thus advancing our understanding of the production sites of the heaviest elements in the universe. The project will train a graduate student in advanced atomic physics methods, provide research opportunities to undergraduate students, and expose high school students to astronomical research. Using modern electronic structure codes, the investigators will calculate and benchmark EII and DR cross sections for ions of important elements produced by the rapid neutron capture process in NSMs. Extensive calculations will yield DR rate coefficients for temperatures consistent with the thermal (low energy) and non-thermal (high energy) electron components in kilonova ejecta. The EII cross sections will allow the investigators to explore the contributions of other ionization mechanisms that are missing from models of kilonova emission. This project advances the goals of the Windows on the Universe Big Idea.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.