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Test of charge-conjugation symmetry via microwave spectroscopy of positronium

R. J. Daly1, K. P. Habdas1, D. M. Newson1, J. Pérez-Ríos2, R. E. Sheldon1, and D. B. Cassidy1

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Phys. Rev. A 112, 062801 – Published 1 December, 2025Erratum Phys. Rev. A 114, 029901 (2026)

DOI: https://doi.org/10.1103/trnb-hgr6

Abstract

The 23S1→21P1 interval in positronium has been measured via microwave spectroscopy. This transition is strictly forbidden by charge conjugation invariance but may be observed in a magnetic field. Extrapolation of the Rabi frequencies obtained from spectral line shapes measured in different fields to the zero field case was used to test for a possible C-violating interaction with Hamiltonian HCV, characterized by the matrix element MCV=〈21P1|HCV|23P1〉. We obtain |MCV|=18.6±6.5MHz and |MCV|=37.2±13.4 MHz for the MJ=±1→±1 and the MJ=0→0 components, respectively.

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Erratum

Erratum: Test of charge-conjugation symmetry via microwave spectroscopy of positronium [Phys. Rev. A 112, 062801 (2025)]

R. J. Daly, K. P. Habdas, D. M. Newson, J. Pérez-Ríos, R. E. Sheldon, and D. B. Cassidy
Phys. Rev. A 114, 029901 (2026)

Article Text

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Phys. Rev. A 112, 062801– Published 1 December, 2025
  • Received 23 July 2025
  • Accepted 30 October 2025
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