# Constraints on Two Higgs Doublet Model Parameters in the light of rare $B$-Decays

## TL;DR

This paper constrains the parameters of the Two Higgs Doublet Model using rare B-meson decay data, providing bounds that help test the model in current and future experiments.

## Contribution

It offers new bounds on 2HDM parameters derived from rare B-decay observables, including constraints from $B\to X_s\gamma$, $B_s\to\mu^+\mu^-$, and $B\to K^*\mu^+\mu^-$ decays.

## Key findings

- $m_{H^{\pm}} > 80$ GeV for $\tan\beta \sim 2$
- Constraints from $B_s\to\mu^+\mu^-$ decay agree with LEP data
- Bounds on $m_H$ and $m_A^0$ from forward-backward asymmetry

## Abstract

We established the allowed parameters of two-Higgs doublet model(2HDM) from flavor physics observables, precisely from rare $B$ meson decays. In our analysis most formidable constraints on the 2HDM parameters arise from the branching ratio of rare radiative $B$ meson decay i.e., $B\to X_{s}\gamma$. However, the constraints arising from the branching ratio of $B_{s}\to\mu^{+}\mu^{-}$ decay in $m_{H^{\pm}}-\tan\beta$ plane give $m_{H^{\pm}} >$ 80 GeV for the value of $\tan\beta\sim 2$, that is in agreement with large electron-positron collider (LEP) data. Furthermore, we also investigate the bounds on the $CP$-even $m_{H}$ and $CP$-odd $m_{A^{0}}$ Higgs boson not only from above mentioned physical observables, but also from the zero crossing of the forward-backward asymmetry of $B\to K^{\ast}\mu^{+}\mu^{-}$ decay. Therefore, these bounds on parameters of the 2HDM will provides a fertile ground to test the 2HDM at current and future $B$-physics experiments.