Collaborative Research: Development of a Relativistic Atomic Code for Accurate Treatment of Complex Correlations

该项目的目标是开发一种广泛适用的原子代码，用于预测开d壳层和f壳层原子的性质，精度达到几个百分点。最近的国家科学基金会原子、分子和光学（AMO）理论研讨会确定了“描述原子分子结构和碰撞中的复杂相关性”作为AMO物理学在未来十年的中心目标，因为它具有基本的重要性和与新实验的相关性。虽然最近在高精度原子计算方面取得了巨大的进展，但精确处理d壳层和f壳层开放系统中的相关性仍然是一个挑战。在本提案中，我们将开发一种新的基于大规模配置交互作用（CI）和可选启动势下进行的全阶线性化耦合簇方法相结合的开源代码。产生的代码集将被记录并提供给科学界。具体的测试案例将在本提案中被选择，因为他们目前对各种应用感兴趣，包括基本常数的变化、天体物理学、原子钟和量子信息处理研究：Fe、Fe+、Xe、Hg+、Yb+和电离Th的开壳态。该代码将被设计用于计算这些领域除了能级和跃迁率之外的特定属性。我们还将制定方法来评估所产生的推荐数据的准确性。本项目考虑的d壳层和f壳层原子对AMO理论提出了前沿挑战，同时也站在许多实验应用的前沿，如基本常数的时间依赖性、基本相互作用研究、原子钟研究、天体物理数据分析、等离子体科学、量子简并气体研究和量子信息。在这些应用中，精确的AMO理论对于实验的设计和解释是必不可少的，直接实验测量相关参数是不可能或不可行的。我们的代码的目标是将d壳层和f壳层原子的处理提升到与现在更简单的系统可能达到的水平：这是一个具有挑战性的前景，将元素周期表的大部分内容开放给迄今为止只能使用最简单原子的应用程序。因此，这项研究将推动基础物理问题的研究和未来技术（如原子钟和量子信息）的发展。除了为科学界开发一种新的广泛适用的原子代码之外，我们建议为新AMO学生的教育和促进理论与实验之间的联系创造工具。我们将开发一套基于前沿研究实例的实际计算的AMO物理学现代应用教程。这些教程可以由不同的小组单独使用，也可以合并到研究生原子物理入门课程“计算原子物理的现代应用”中。由此产生的教育教程将通过PI网站或其他适当的网络资源数据库传播，与其他教育工作者共享，并酌情在教育期刊上发表。

The goal of this project is to develop a broadly applicable atomic code for predicting properties of open d- and f-shell atoms with precision of a few percent. The recent NSF Workshop on Atomic, Molecular and Optical (AMO) Theory identified "describing complex correlations in atomic -molecular structure and collisions" as a central objective of AMO physics in the coming decade, due to its fundamental importance and relevance to new experiments. While tremendous progress has been made recently in high-precision atomic calculations, accurate treatment of correlations in d- and f-shell open systems remains a challenge. In this proposal, we will develop a new open-source code based on the combination of large-scale configuration interaction (CI) and all-order linearized coupled-cluster method carried out in the optional starting potential. The resulting set of codes will be documented and made available for the scientific community. Specific test cases that will be treated in this proposal are selected for their present interest to various applications including variation of fundamental constants, astrophysics, atomic clocks, and quantum information processing research: open-shell states of Fe, Fe+, Xe, Hg+, Yb+, and ionized Th. The code will be designed to calculate specific properties of interest to these fields beyond energy levels and transition rates. We will also develop methodologies to evaluate the accuracy of the produced recommended data. The d- and f-shell atoms considered in this project present frontier challenges to AMO theory, and also stand in the forefront of a number of experimental applications to subjects such as time-dependence of the fundamental constants, studies of fundamental interactions, atomic clock research, analysis of astrophysical data, plasma science, studies of quantum degenerate gases, and quantum information. In a number of these applications, accurate AMO theory is indispensable to the design and interpretation of experiments, with direct experimental measurement of relevant parameters being impossible or infeasible. Our code has the goal of elevating treatment of d- and f-shell atoms to the same level now possible for simpler systems: a challenging prospect that opens up much of the Periodic Table to applications that heretofore could only be pursued with the simplest atoms. Therefore, this research will lead to the advancement of both the study of fundamental physics questions and development of future technologies (such as atomic clocks and quantum information). Beyond the development for the scientific community of a new broadly applicable atomic code we propose to create tools for education of the new AMO students and promotion of the connection between theory and experiment. We will develop a set of tutorials on modern applications of the AMO physics that will be based on practical calculations of examples from forefront research. These tutorials may be used separately by various groups or combined into introductory graduate atomic physics course "Modern Applications of Computational Atomic Physics". The resulting educational tutorials will be disseminated through the PI web-site or other appropriate web resource databases, shared with other educators and published in educational journals as appropriate.