New atomic data for Ge XX

Waleed Othman Younis; Alan Hibbert

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arXiv · 1508.03591

New atomic data for Ge XX

Waleed Othman Younis·Alan Hibbert

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Abstract

We have performed large-scale configuration interaction (CI) calculations using CIV3for the lowest (in energy) 155 fine-structure levels of aluminum-like germanium ion. We have calculated the energy levels, lifetimes, oscillator strengths, and transition probabilities for the electric-dipole allowed and intercombination transitions among the levels of ground state3s23p(2P)and higher energy levels of states3s3p2, 3s23d, 3p3, 3s3p3d, 3p23d, 3s3d2,3p3d2, 3d3,3s2(4s, 4p, 4d, 4f) ofGe XX in the LSJ coupling scheme.The present results include relativistic effects through the Breit-Pauli operator. In order to keep our calculated energy splittings as close as possible to the experimental and theoretical results complied by NIST, we attempt to correct the inaccuracies in the CI coefficients in the wavefunctions, which would lead to inaccuracies in transition probabilities, by applying a "fine-tuning" technique. Fine-tuning of the ab initio energies was donethrough adjusting, by a small amount, some diagonal elements of the Hamiltonian matrix.Comparisons are made with other available experimental and theoretical results and the accuracy of the present results is assessed.

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Waleed Othman Younis, Alan Hibbert. 2015-05-13. New atomic data for Ge XX. https://arxiv.org/abs/1508.03591

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