Indirect reach of heavy MSSM Higgs bosons by precision measurements at future lepton colliders

TL;DR

Future lepton colliders can indirectly detect heavy MSSM Higgs bosons by precisely measuring Higgs decay ratios, revealing deviations from the Standard Model due to non-decoupling effects.

Contribution

This paper demonstrates how precision measurements of Higgs decay ratios at future colliders can indirectly probe heavy MSSM Higgs bosons beyond direct detection capabilities.

Findings

Higgs decay ratio to bottom quarks and W bosons is highly sensitive to heavy MSSM Higgs effects.

Planned ILC measurements can extend the discovery reach for MSSM Higgs bosons.

Non-decoupling effects cause measurable deviations from Standard Model predictions.

Abstract

In the Minimal Supersymmetric Standard Model (MSSM), the bottom Yukawa coupling of the Higgs boson can considerably deviate from its Standard Model prediction due to non-decoupling effects. We point out that the ratio of the Higgs boson decay branching fraction to a bottom quark pair and that to a $W$-boson pair from the same production channel is particularly sensitive to large additional MSSM Higgs boson mass regions at future electron-positron colliders. Based on this precision measurement, we explicitly show the indirect discovery reach of the additional Higgs bosons according to planned programs of the International Linear Collider.