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.
