Type-II Seesaw Higgs triplet productions and decays at the LHC

TL;DR

This paper thoroughly analyzes the production and decay of all non-standard scalar particles in the Type-II Seesaw Model at the LHC, emphasizing scenarios with suppressed lepton-number violation and providing detailed search strategies.

Contribution

It offers the first comprehensive classification of cascade decays of all scalar states in the model and presents detailed LHC search prospects for neutral and charged scalars.

Findings

Identifies key parameter sensitivities affecting LHC searches.

Provides detailed decay classifications and multiplicities.

Demonstrates search strategies with benchmark points.

Abstract

The Type-II Seesaw Model provides an attractive scenario to account for Majorana-neutrino masses. Its extended Higgs sector, if sufficiently light, can have a rich and distinctive phenomenology at the LHC while yielding automatically an essentially Standard-Model-Higgs-like state. Several phenomenological studies have been devoted to the scalar sector of this model, as well as experimental searches focusing mostly on the (doubly-)charged states. In this paper we present an exhaustive study of the main production and decay channels of all the non-standard scalar states originating from the $SU(2)_L$ doublet and a complex triplet of the model. We stick to scenarios where lepton-number-violating decays are suppressed, for which present experimental limits are still weak, highlighting theoretical parameter sensitivities that were not previously emphasized in the literature and the uncertainties they can induce for the experimental searches at the LHC. A comprehensive classification of the various cascade decays and corresponding Standard Model particle multiplicities is provided. As an illustration, a detailed prospective search study at the LHC with an ATLAS-like detector is carried out on some benchmark points, for charged, doubly-charged, and, for the first time, neutral state productions