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。这项研究项目将计算中子星合并(NSM)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千新星的光谱，千新星是由NSM抛出的物质发出的瞬变电磁辐射，从而促进我们对宇宙中最重元素的产生地点的理解。该项目将培训一名研究生学习先进的原子物理方法，为本科生提供研究机会，并让高中生接触天文研究。使用现代电子结构代码，研究人员将计算NSM中快速中子捕获过程产生的重要元素离子的EII和DR截面，并对其进行基准测试。广泛的计算将得到与千里诺瓦喷出物中热(低能)和非热(高能)电子成分一致的温度的DR率系数。EII截面将使研究人员能够探索千诺瓦发射模型中缺失的其他电离机制的贡献。这个项目推进了宇宙大理想之窗的目标。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势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.