Electroweak breaking and neutrino mass: "invisible" Higgs decays at the LHC (Type II seesaw)

TL;DR

This paper explores how neutrino mass generation via the type-II seesaw model affects electroweak symmetry breaking and predicts new Higgs decay channels, including invisible decays, with implications for LHC searches.

Contribution

It analyzes the impact of the type-II seesaw model on Higgs phenomenology, especially invisible decays, and assesses experimental sensitivities at the LHC.

Findings

Potential detection of invisible Higgs decays at the LHC

Enhanced Higgs decay channels beyond the Standard Model

Constraints on the type-II seesaw model from collider data

Abstract

Neutrino mass generation through the Higgs mechanism not only suggests the need to reconsider the physics of electroweak symmetry breaking from a new perspective, but also provides a new theoretically consistent and experimentally viable paradigm. We illustrate this by describing the main features of the electroweak symmetry breaking sector of the simplest type-II seesaw model with spontaneous breaking of lepton number. After reviewing the relevant "theoretical" and astrophysical restrictions on the Higgs sector, we perform an analysis of the sensitivities of Higgs boson searches at the ongoing ATLAS and CMS experiments at the LHC, including not only the new contributions to the decay channels present in the Standard Model (SM) but also genuinely non-SM Higgs boson decays, such as "invisible" Higgs boson decays to majorons. We find sensitivities that are likely to be reached at the upcoming Run of the experiments.