On the Robustness of type-II Seesaw Collider Searches

TL;DR

This paper examines how extended models of the type-II seesaw mechanism affect collider search strategies for exotic Higgs particles, highlighting the importance of considering new physics contributions in experimental constraints.

Contribution

It provides a systematic analysis of how extensions to the type-II seesaw alter collider phenomenology and the robustness of existing constraints.

Findings

Modified production and decay patterns of exotic Higgs particles.

Extended models can weaken or strengthen collider constraints.

Robustness of current bounds depends on specific model extensions.

Abstract

Electroweak triplet Higgs sector extensions are well-motivated scenarios to address lepton flavour 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.