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Importance of unitarity in the search for heavy neutrinos in e+e−→W+W−

G. A. Chachava1 and S. I. Godunov2

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Phys. Rev. D 114, 055001 – Published 1 September, 2026

DOI: https://doi.org/10.1103/p5nw-316c

Abstract

We study the process e+e−→W+W− with the aim of estimating the prospects for observing heavy neutrino contributions at future e+e−-colliders. In this work, we consider two implementations of heavy-light neutrino mixing: a linearized mixing approximation applied in popular models and an exact unitary mixing scheme. We conclude that the approximate realization leads to physically incorrect results for this process, while exact unitary mixing provides some signatures that can be experimentally checked.

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Phys. Rev. D 114, 055001– Published 1 September, 2026
  • Received 14 April 2026
  • Accepted 5 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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