RUI: Valence and Inner-shell Negative Ion Spectroscopy

这个RUI项目通过两个系列的实验研究光子与负离子的相互作用。 负离子中的额外电子主要受电子相关效应的约束，因此负离子为关于这些多体相互作用的最先进的原子物理计算提供了肥沃的试验场。 在第一系列实验中，将在丹尼森大学校园内使用可调谐红外激光分离外层电子来研究镧系负离子。 镧系元素是人们最不了解的原子负离子之一，它的电子亲合势和共振结构将得到精确的测量。第二系列实验将在劳伦斯伯克利国家实验室的高级光源（ALS）同步加速器上使用紫外线和X射线光子研究负离子（例如硒和碳-60）的内壳光分离。 这些实验延续了PI的一系列研究，调查负离子的短寿命激发态和多电子衰变过程。该计划的更广泛影响包括本科生的教育和与其他科学领域的联系。该项目将加强丹尼森大学的研究和教学基础设施。 学生将参加校园和ALS的实验，为年轻科学家提供重要的研究经验，包括电子，计算机，激光和光学方面的技术培训。对负离子的详细研究将有助于深入了解动力学多体相互作用，这是物理学，化学和材料科学中广泛领域感兴趣的普遍现象。

This RUI project studies the interactions of photons with negative ions in two series of experiments. The extra electron in a negative ion is bound predominantly by electron correlation effects and therefore negative ions provide a fertile testing ground for state-of-the-art atomic physics calculations regarding these multi-body interactions. In the first series of experiments, lanthanide negative ions will be investigated on-campus at Denison University using tunable infrared laser light to detach outer-shell electrons. Accurate measurements will be made of the electron affinities and resonance structure of the lanthanides, which are among the least well-understood atomic negative ions. The second series of experiments will investigate inner-shell photodetachment from negative ions, such as selenium and carbon-60, using ultraviolet and X-ray photons at the Advanced Light Source (ALS) synchrotron at Lawrence Berkeley National Laboratory. These experiments continue a series of studies by the PIs investigating short-lived excited states of negative ions and multi-electron decay processes.The broader impacts of the program include the education of undergraduate students and connections to other scientific fields. The project will enhance the research and teaching infrastructure of Denison University, an undergraduate college. Students will participate in the experiments both on-campus and at the ALS, providing important research experiences for young scientists including technical training in electronics, computers, lasers and optics. The detailed studies of negative ions will yield insights into dynamical many-body interaction, which is a general phenomenon of interest for a broad range of fields in physics, chemistry, and materials science.