Zh Production, a Tool to Constrain 2HDM

TL;DR

This paper explores how differences in the production cross section of the Higgs boson and Z boson in the 2HDM compared to the SM can be used to discover or constrain the 2HDM, especially with LHC measurements.

Contribution

It introduces a method to constrain 2HDM parameter space using Higgs-Z production cross section differences and LHC data.

Findings

Allowed parameter space of 2HDM type-II is significantly constrained.

Combination of LHC measurements with previous constraints rules out large parts of 2HDM.

Precise measurements can effectively test 2HDM viability.

Abstract

Since the SM Higgs boson, h, is the superposition of two unequal-mass neutral Higgs bosons in 2HDM, therefore the associated production cross section for h and Z in SM and 2HDM can be different. In this paper, the possibility of using this difference to discover or constrain 2HDM is studied. As a main result, the allowed parameter space of 2HDM type-II is found in the light of possible precise measurements from the LHC experiments. It is shown that combination of the constraints from these measurements with the previous constraints on 2HDM, from direct search and flavour physics, can rule out the main part of the 2HDM parameter space.