# Leptophilic neutral Higgs bosons in two Higgs doublet model at a linear collider

## TL;DR

This study explores the potential to detect leptophilic neutral Higgs bosons in a two Higgs doublet model at future linear colliders, demonstrating observable signals with specific decay channels and collider parameters.

## Contribution

It introduces a detailed analysis of leptonic decay signatures of neutral Higgs bosons in a type IV 2HDM at linear colliders, including benchmark scenarios and detection prospects.

## Key findings

- Signal can be observed at 1000 fb^{-1} luminosity
- Clear di-muon invariant mass signals away from Z pole
- Effective tau-jet event preselection algorithm

## Abstract

This paper addresses the question of observability of neutral Higgs bosons through the leptonic decay in a two Higgs doublet model (2HDM). Both scalar and pseudoscalar Higgs bosons ($H,~A$) are considered. The model is set to type IV to enhance the leptonic decay. In such a scenario, a signal production process like $e^+e^- \to A^0H^0 \to \tau\tau \mu\mu$ or $\mu\mu\tau\tau$ would provide a clear signal on top of the background in a di-muon invariant mass distribution far from the $Z$ boson pole mass. The analysis is based on a $\tau$-id algorithm which preselects events if they have two $\tau$ jets by requiring a hadronic $\tau$ decay. Several benchmark points are defined for the search, requiring a linear collider operating at $\sqrt{s} =$ 0.5 and 1 TeV. It is shown that the signal can be observed on top of the background in all benchmark points at an integrated luminosity of 1000 $fb^{-1}$.