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Excited Σ states of the hydrogen-antihydrogen molecule

L. Brumm1, J. Schürmann1,2, and A. Saenz1

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Phys. Rev. A 113, 062801 – Published 5 June, 2026

DOI: https://doi.org/10.1103/x3xl-sxzr

Abstract

Adopting explicitly correlated Kołos-Wolniewicz-type basis functions, the Born-Oppenheimer potential curves of a number of excited Σ states of the hydrogen-antihydrogen system (HH¯) were calculated for both, even and odd, Q symmetries, including also free positronium states. It is demonstrated that the excited leptonic states support rovibrational states with energies close to the ground-state dissociation threshold. As a consequence, the excited leptonic states need to be considered in theoretical treatments of ground-state H–H¯ collisions.

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Phys. Rev. A 113, 062801– Published 5 June, 2026
  • Received 12 November 2025
  • Accepted 6 May 2026
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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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