Search for an exotic decay of the Higgs boson to a pair of light pseudoscalars in the final state of two muons and two $\tau$ leptons in proton-proton collisions at $\sqrt{s}=$ 13 TeV

TL;DR

This study searches for rare Higgs decays into light pseudoscalars in specific final states using LHC data, setting limits on such processes within extended two-Higgs-doublet models.

Contribution

First search for Higgs decays to light pseudoscalars in muon and tau final states at 13 TeV using CMS data, constraining new physics models.

Findings

No significant excess observed over standard model predictions.

Upper limits set on Higgs to pseudoscalar branching fractions.

Mass range of pseudoscalars between 15 and 62.5 GeV probed.

Abstract

A search for exotic Higgs boson decays to light pseudoscalars in the final state of two muons and two $\tau$ leptons is performed using proton-proton collision data recorded by the CMS experiment at the LHC at a center-of-mass energy of 13 TeV in 2016, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. Masses of the pseudoscalar boson between 15.0 and 62.5 GeV are probed, and no significant excess of data is observed above the prediction of the standard model. Upper limits are set on the branching fraction of the Higgs boson to two light pseudoscalar bosons in different types of two-Higgs-doublet models extended with a complex scalar singlet.