Hunting a charged Higgs boson pair in proton-proton collisions

TL;DR

This paper investigates the potential detection of charged Higgs boson pairs at the LHC within the 2HDM-III framework, identifying promising scenarios and predicting a possible 5-sigma discovery in the 100-350 GeV mass range.

Contribution

It introduces specific scenarios in 2HDM-III that could be experimentally tested at HL-LHC, linking theoretical predictions with current experimental excesses.

Findings

Identifies parameter regions consistent with current ATLAS excess.

Predicts a 5-sigma signal significance for charged Higgs masses 100-350 GeV.

Proposes realistic experimental scenarios for HL-LHC detection.

Abstract

We explore the production and possible detection of a charged scalar Higgs pair $H^-H^+$ decaying into the final state $\mu\nu_{\mu}cb$ in proton-proton collisions at the LHC and its next step, the High Luminosity LHC (HL-LHC). The charged scalars are predicted within the theoretical framework of the Two-Higgs Doublet Model of type III (2HDM-III). As a test and validation of the model, we identify regions of the 2HDM-III parameter space that accommodate the current excess of events at $3\sigma$ in the process $\mathcal{BR}(t\to H^{\pm}b)\times \mathcal{BR}(H^{\pm}\to cb)$ for $M_{H^{\pm}}=130$ GeV, as reported by the ATLAS collaboration. Theoretical and additional experimental constraints are also included. Based on this, we propose realistic scenarios that could be brought under experimental scrutiny at the HL-LHC. Assuming the most favorable scenario, we predict a signal significance at the level of $5\sigma$ for a charged scalar boson mass $M_{H^{\pm}}$ in the $100-350$ GeV range.