Scalar sector of Type 2 Seesaw model explorations with multi-lepton final states

TL;DR

This paper provides a comprehensive phenomenological analysis of the scalar sector in the Type 2 Seesaw model, focusing on multi-lepton final states at the LHC, highlighting new sensitivities and proposing search strategies for future experiments.

Contribution

It offers the first detailed study of neutral scalar production in the Type 2 Seesaw model, emphasizing a previously overlooked sensitivity to a mixing angle and proposing experimental search strategies.

Findings

Identified key production and decay channels for scalars at the LHC.

Highlighted sensitivity to a mixing angle affecting detection prospects.

Proposed search strategies for multi-lepton, jets, and missing energy final states.

Abstract

Originally motivated for the generation of (Majorana) neutrino masses, the Type 2 Seesaw Model has also a rich extended Higgs sector with, if accessible at the LHC, a distinctive phenomenology of neutral, charged and doubly-charged states. The goal of the work is to present an exhaustive phenomenological study of the most promising production and decay channels of pair or associated scalars, decaying directly or in cascades to Standard Model particles at the LHC. The study is complementary to the literature in that it highlights a previously unnoticed important sensitivity to a mixing angle. The ensuing uncertainty calls for a comprehensive experimental search strategy for the various processes. These processes can be studied within LHC energies reach, by comparing cutflow results for different final states. We carried out prospective search analyses with multi-lepton, jets and missing energy configurations, assuming an ATLAS-like detector at LHC and HL-LHC, for charged, doubly-charged, and for the first time neutral scalar productions. The work is a collaboration between ATLAS experimentalists and theoreticians in continuation of an endeavor that lead to previous published ATLAS analyses for the search of (doubly)charged Higgs bosons, aiming at proposals for future experimental searches.