Parameter dependence and analysis of the 2HDM neutral Higgs boson pair production and decay at future lepton colliders

TL;DR

This paper analyzes the production and decay of neutral Higgs bosons in the 2HDM at future lepton colliders, identifying promising channels and exploring parameter space regions beyond current LHC exclusions.

Contribution

It provides a comprehensive parameter-dependent analysis of 2HDM Higgs boson processes at future colliders, including collider simulation and exclusion prospects.

Findings

Future lepton colliders can probe new 2HDM parameter regions

Identification of promising Higgs production and decay channels

Potential to exclude or discover 2HDM scenarios beyond LHC reach

Abstract

In this work, we present a study of the neutral Higgs bosons in the two Higgs doublet model (2HDM) in terms of their production processes and decay channels as a function of the model parameters. The analysis is performed for all four types of the 2HDM and the most promising processes and decay channels are identified for each type of the model. Several Higgs boson mass scenarios below and above the threshold of decay to gauge boson pair are introduced and the corresponding categories of final states are analyzed. The event analysis including collider beam spectrum and detector simulation shows that future lepton colliders have the potential to explore regions in the 2HDM parameter space, which have not yet been excluded by LHC, in a few weeks of operation. Final results are presented in terms of the signal distributions on top of the background and 95% CL exclusion and 5$\sigma$ contours based on center of mass energy of $\sqrt{s}$ = 500 GeV at the Compact Linear Collider (CLIC) or International Linear Collider (ILC).