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arXiv · 2001.02011

Accurate determination of energy levels, hyperfine structure constants, lifetimes and dipole polarizabilities of triply ionized tin isotopes

Abstract

We have investigated energies, magnetic dipole hyperfine structure constants ($A_{hyf}$) and electric dipole (E1) matrix elements of a number of low-lying states of the triply ionized tin (Sn$^{3+}$) by employing relativistic coupled-cluster theory. Contributions from the Breit interaction and lower-order quantum electrodynamics (QED) effects in determination of above quantities are also given explicitly. These higher-order relativistic effects are found to be important for accurate evaluation of energies, while QED contributions are seen to be contributing significantly to the determination of $A_{hyf}$ values. Our theoretical results for energies are in agreement with one of the measurements but show significant differences for some states with another measurement. Reported $A_{hyf}$ will be useful in guiding measurements of hyperfine levels in the stable isotopes of Sn$^{3+}$. The calculated E1 matrix elements are further used to estimate oscillator strengths, transition probabilities and dipole polarizabilities ($\alpha$) of many states. Large discrepancies between present results and previous calculations of oscillator strengths and transition probabilities are observed for a number of states. The estimated $\alpha$ values will be useful for carrying out high precision measurements using Sn$^{3+}$ ion in future experiments.

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Mandeep Kaur, Rishabh Nakra, Bindiya Arora, Cheng-Bin Li, B. K. Sahoo. 2020-01-07. Accurate determination of energy levels, hyperfine structure constants, lifetimes and dipole polarizabilities of triply ionized tin isotopes. https://doi.org/10.1088/1361-6455/ab68b7

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