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Magnetic hyperfine structure constants of BaF137 in the Π1/22 and Π3/22 excited states

Yuly Chamorro1,*, Felix Kogel2, Tim Langen2,3, and Anastasia Borschevsky1

  • 1Van Swinderen Institute for Particle Physics and Gravity, University of Groningen, 9747 AG Groningen, The Netherlands
  • 25. Physikalisches Institut and Center for Integrated Quantum Science and Technology, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany
  • 3Vienna Center for Quantum Science and Technology, Atominstitut, TU Wien, Stadionallee 2, A-1020 Vienna, Austria

  • *Contact author: y.a.chamorro.mena@rug.nl
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Phys. Rev. A 112, 042808 – Published 9 October, 2025

DOI: https://doi.org/10.1103/sksm-t85m

Abstract

High-precision molecular experiments testing the Standard Model of particle physics require an accurate understanding of the molecular structure at the hyperfine level, both for the control of the molecules and for the interpretation of the results. In this work, we calculate the hyperfine structure constants for the excited states Π1/22 and Π3/22 of BaF137 due to the Ba137 nucleus. We use the four-component relativistic Fock-space coupled-cluster method, extrapolating our results to the complete basis set limit. We investigate the effect of the basis sets and electron correlation, and estimate the uncertainty in our final results. Our results are used in the interpretation of the experimental spectroscopy of the hyperfine and rovibrational spectra of BaF, and the planning of laser-cooling schemes for future parity-violating anapole moment measurements [Kogel et al., Phys. Rev. A 112, 042807 (2025)].

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High-resolution spectroscopy of barium monofluoride: Odd isotopologues, hyperfine structure, and isotope shifts

Felix Kogel, Yuly Chamorro, Mangesh Bhattarai, Marian Rockenhäuser, Tatsam Garg, David DeMille, Anastasia Borschevsky, and Tim Langen
Phys. Rev. A 112, 042807 (2025)

Article Text

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Outline

Information

Phys. Rev. A 112, 042808– Published 9 October, 2025
  • Received 3 July 2025
  • Accepted 27 August 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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