Measuring extended Higgs sectors as a consistent free couplings model

TL;DR

This paper analyzes extended Higgs sectors, including singlet-doublet and two-doublet models, using current LHC Higgs coupling data to constrain parameters and demonstrate their viability as UV completions of the Standard Model Higgs.

Contribution

It provides a comprehensive study of Higgs coupling patterns in extended sectors and shows how two-doublet models can serve as consistent UV completions with free couplings.

Findings

Current Higgs data constrains extended Higgs models.

Two-doublet models can act as UV completions of the Standard Model Higgs.

Quantum corrections are included in the analysis.

Abstract

Extended Higgs sectors appear in many models for physics beyond the Standard Model. Current Higgs measurements at the LHC are starting to significantly constrain them. We study their Higgs coupling patterns at tree level as well as including quantum corrections. Our benchmarks include a dark singlet-doublet extension and several two-doublet setups. Using SFitter we translate the current Higgs coupling measurements for one light Higgs state into their respective parameter spaces. Finally, we show how two-Higgs-doublet models can serve as a consistent ultraviolet completion of an assumed single Standard-Model-like Higgs boson with free couplings.