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Forward-backward asymmetry in the H→Zγ→f¯fγ decay

A. I. Hernández-Juárez*, D. Watko, A. Fernández-Téllez, and G. Tavares-Velasco

  • *Contact author: alan.hernandezjua@alumno.buap.mx
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Phys. Rev. D 114, 055036 – Published 21 September, 2026

DOI: https://doi.org/10.1103/7ctd-6fmw

Abstract

We study the forward-backward asymmetry in the three-body decay process H→Zγ→f¯fγ, induced by complex form factors in the HZγ vertex. To estimate its magnitude, we derive constraints on the real and imaginary parts of the CP-violating form factor h3Zγ using current LHC measurements, obtaining upper limits of about 0.9 GeV. These bounds are of the same order of magnitude as those derived from electric dipole moments. We find that the asymmetry can reach values of order 10−1 and may be accessible at the HL-LHC.

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Phys. Rev. D 114, 055036– Published 21 September, 2026
  • Received 6 May 2026
  • Accepted 17 August 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. Funded by SCOAP3.

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