tan$\beta$ determination from the Higgs boson decay at the International Linear Collider

TL;DR

This paper explores methods to determine tanβ in two Higgs doublet models at future lepton colliders, proposing a new approach using precise measurements of the SM-like Higgs decay, which can outperform existing methods.

Contribution

It introduces a novel method based on Higgs decay branching ratios for measuring tanβ, applicable when deviations from the Standard Model are observed.

Findings

The new method can provide high sensitivity across a wide tanβ range.

It complements existing methods based on additional Higgs boson production.

Sensitivity depends on the type of Yukawa interactions.

Abstract

We study the methods and their accuracies for determining tan$\beta$ in two Higgs doublet models at future lepton colliders. In addition to the previously proposed methods using direct production of additional Higgs bosons, we propose a method using the precision measurement of the decay branching ratio of the standard-model (SM)-like Higgs boson. The method is available if there is a deviation from the SM in the coupling constants of the Higgs boson with the weak gauge bosons. We find that, depending on the type of Yukawa interactions, this method can give the best sensitivity in a wide range of tan\beta.