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Robustness of type-II seesaw model collider searches

Christoph Englert1,*, Manimala Mitra3,4,†, Wrishik Naskar2,‡, and Subham Saha3,4,§

  • *Contact author: christoph.englert@manchester.ac.uk
  • †Contact author: manimala@iopb.res.in
  • ‡Contact author: wrishik.naskar@desy.de
  • §Contact author: subham.saha@iopb.res.in
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Phys. Rev. D 114, 035033 – Published 24 August, 2026

DOI: https://doi.org/10.1103/brqh-cx6l

Abstract

Electroweak triplet Higgs sector extensions are well-motivated scenarios to address lepton flavor observations. These models can also be strongly constrained by combining precise, indirect low-energy measurements with direct searches for exotic, doubly-charged Higgs bosons. Together, these searches set competitive constraints on the type-II seesaw mechanism. In this work, we consider extensions of the type-II seesaw, specifically through the lens of a modified collider phenomenology. Surveying motivated extensions, we map out changes in expected correlations, focusing on the modified production and decay phenomenology of exotic Higgs particles. This enables us to assess the robustness of the type-II seesaw collider constraints against extended new-physics contributions that modify standard sensitivity expectations and projections.

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Phys. Rev. D 114, 035033– Published 24 August, 2026
  • Received 27 March 2026
  • Accepted 21 July 2026
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