Light charged Higgs boson scenario in 3HDMs

TL;DR

This paper explores a novel light charged Higgs boson scenario in 3-Higgs-Doublet Models, where the charged Higgs predominantly decays into cb, differing from 2HDMs and consistent with experimental constraints.

Contribution

It introduces a new light charged Higgs boson decay mode in 3HDMs, expanding the possibilities beyond 2HDMs and aligning with current experimental data.

Findings

Charged Higgs can decay mainly into cb in 3HDMs.

This scenario is incompatible with 2HDMs.

The proposed decay mode is consistent with LHC and B-physics constraints.

Abstract

The measurement of the $B\to X_s\gamma$ process gives important constraints on physics related to charged Higgs bosons ($H^\pm$). In 2-Higgs Doublet Models (2HDMs) with a softly-broken $Z_2$ symmetry, a light $H^\pm$ scenario, in which $H^\pm$ can be produced via the top decay, is possible in two of four types of Yukawa interactions (the so-called Type-I and Type-X). In these types of 2HDMs, the $H^\pm \to \tau^\pm \nu$ decay mode is dominant in wide regions of the parameter space. In this report, we discuss the other possibility of a light charged Higgs boson scenario in 3-Higgs-Doublet Models (3HDMs) based on the results obtained in Ref. [1]. We show that charged Higgs bosons can mainly decay into $cb$ without contradiction with the $B\to X_s\gamma$ data and the direct searches for charged Higgs bosons at the LHC, and this scenario cannot be realized in the 2HDMs.