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arXiv · 2207.14001

FitAik: a package to calculate least-square fitted atomic transitions probabilities. Application to the Er+ lanthanide ion

Maxence Lepers·Olivier Dulieu·Jean-François Wyart
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Abstract

We present a new method implemented in our new package \textit{FitAik}, to perform least-squares fitting of calculated and experimental atomic transition probabilities, by using the mono-electronic transition integrals $\langle n\ell |r| n'\ell' \rangle$ (with $r$ the electronic radial coordinate) as adjustable quantities. \textit{FitAik} is interfaced to the Cowan suite of codes, for which it automatically writes input files and reads output files. We illustrate our procedure with the example of Er$^{+}$ ion, for which the agreement between calculated and experimental Einstein coefficients is found to be very good. The source code of \emph{FitAik} can be found on GitLab, and the calculated Einstein coefficients are stored in our new database CaDDiACs. They are also used to calculate the dynamic dipole polarizability of Er$^+$.

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Maxence Lepers, Olivier Dulieu, Jean-François Wyart. 2022-07-28. FitAik: a package to calculate least-square fitted atomic transitions probabilities. Application to the Er+ lanthanide ion. https://arxiv.org/abs/2207.14001

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