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Title: Relativistic many-body investigation of hyperfine interactions in excited S states of alkali metals: Francium and potassium

Abstract

To enhance the current understanding of mechanisms contributing to magnetic hyperfine interactions in excited states of atomic systems, in particular, alkali-metal atom systems, the hyperfine fields in the excited 5{sup 2}S{sub 1/2}{endash}8{sup 2}S{sub 1/2} states of potassium and 8{sup 2}S{sub 1/2}{endash}12{sup 2}S{sub 1/2} states of francium atoms have been studied using the relativistic linked-cluster many-body perturbation procedure. The net theoretical values of the hyperfine fields for the excited states studied are in excellent agreement with available experimental data for both atoms. There is a significant decrease in importance of the correlation contribution in going from the ground state to the excited states, the correlation contributions as ratios of the direct contribution decreasing rapidly as one moves to the higher excited states. However, the contribution from the exchange core polarization (ECP) effect is nearly a constant fraction of the direct effect for all the excited states considered. Physical explanations are offered for the observed trends in the contributions from the different mechanisms. A comparison is made of the different contributing effects to the hyperfine fields in potassium and francium to those in the related system, rubidium, studied earlier. Extrapolating from our results to the highly excited states of alkali-metal atoms, referredmore » to as the Rydberg states, it is concluded that in addition to the direct contribution from the excited valence electron to the hyperfine fields, a significant contribution is expected from the ECP effect arising from the influence of exchange interactions between electrons in the valence and core states. {copyright} {ital 1997} {ital The American Physical Society}« less

Authors:
; ; ;  [1];  [2]
  1. Department of Physics, State University of New York at Albany, Albany, New York, 12222 (United States)
  2. Technische Natuurkunde, Technische Universiteit Delft, 2628 CJ Delft (The Netherlands)
Publication Date:
OSTI Identifier:
531772
Resource Type:
Journal Article
Journal Name:
Physical Review A
Additional Journal Information:
Journal Volume: 56; Journal Issue: 1; Other Information: PBD: Jul 1997
Country of Publication:
United States
Language:
English
Subject:
66 PHYSICS; POTASSIUM; HYPERFINE STRUCTURE; EXCITED STATES; FRANCIUM; RYDBERG STATES; GROUND STATES; S STATES; POLARIZATION

Citation Formats

Owusu, A, Dougherty, R W, Gowri, G, Das, T P, and Andriessen, J. Relativistic many-body investigation of hyperfine interactions in excited S states of alkali metals: Francium and potassium. United States: N. p., 1997. Web. doi:10.1103/PhysRevA.56.305.
Owusu, A, Dougherty, R W, Gowri, G, Das, T P, & Andriessen, J. Relativistic many-body investigation of hyperfine interactions in excited S states of alkali metals: Francium and potassium. United States. https://doi.org/10.1103/PhysRevA.56.305
Owusu, A, Dougherty, R W, Gowri, G, Das, T P, and Andriessen, J. 1997. "Relativistic many-body investigation of hyperfine interactions in excited S states of alkali metals: Francium and potassium". United States. https://doi.org/10.1103/PhysRevA.56.305.
@article{osti_531772,
title = {Relativistic many-body investigation of hyperfine interactions in excited S states of alkali metals: Francium and potassium},
author = {Owusu, A and Dougherty, R W and Gowri, G and Das, T P and Andriessen, J},
abstractNote = {To enhance the current understanding of mechanisms contributing to magnetic hyperfine interactions in excited states of atomic systems, in particular, alkali-metal atom systems, the hyperfine fields in the excited 5{sup 2}S{sub 1/2}{endash}8{sup 2}S{sub 1/2} states of potassium and 8{sup 2}S{sub 1/2}{endash}12{sup 2}S{sub 1/2} states of francium atoms have been studied using the relativistic linked-cluster many-body perturbation procedure. The net theoretical values of the hyperfine fields for the excited states studied are in excellent agreement with available experimental data for both atoms. There is a significant decrease in importance of the correlation contribution in going from the ground state to the excited states, the correlation contributions as ratios of the direct contribution decreasing rapidly as one moves to the higher excited states. However, the contribution from the exchange core polarization (ECP) effect is nearly a constant fraction of the direct effect for all the excited states considered. Physical explanations are offered for the observed trends in the contributions from the different mechanisms. A comparison is made of the different contributing effects to the hyperfine fields in potassium and francium to those in the related system, rubidium, studied earlier. Extrapolating from our results to the highly excited states of alkali-metal atoms, referred to as the Rydberg states, it is concluded that in addition to the direct contribution from the excited valence electron to the hyperfine fields, a significant contribution is expected from the ECP effect arising from the influence of exchange interactions between electrons in the valence and core states. {copyright} {ital 1997} {ital The American Physical Society}},
doi = {10.1103/PhysRevA.56.305},
url = {https://www.osti.gov/biblio/531772}, journal = {Physical Review A},
number = 1,
volume = 56,
place = {United States},
year = {Tue Jul 01 00:00:00 EDT 1997},
month = {Tue Jul 01 00:00:00 EDT 1997}
}