Search for a charged Higgs boson decaying into a heavy neutral Higgs boson and a W boson in proton-proton collisions at $\sqrt{s}$ = 13 TeV

TL;DR

This paper reports the first search at the LHC for a charged Higgs boson decaying into a heavy neutral Higgs and a W boson, setting upper limits on production cross sections for masses between 300 and 700 GeV.

Contribution

It introduces the first limits on H$^ extpm$ production via the H$^ extpm$ $ o$ HW$^ extpm$ decay channel at the LHC, using CMS data from 2016-2018.

Findings

No significant excess over the standard model background.

Upper limits on cross section times branching fraction range from 0.085 pb to 0.019 pb.

Limits are set for H$^ extpm$ masses from 300 to 700 GeV.

Abstract

A search for a charged Higgs boson H$^\pm$ decaying into a heavy neutral Higgs boson H and a W boson is presented. The analysis targets the H decay into a pair of tau leptons with at least one of them decaying hadronically and with an additional electron or muon present in the event. The search is based on proton-proton collision data recorded by the CMS experiment during 2016-2018 at $\sqrt{s}$ = 13 TeV, corresponding to an integrated luminosity of 138 fb$^{-1}$. The data are consistent with standard model background expectations. Upper limits at 95% confidence level are set on the product of the cross section and branching fraction for an H$^\pm$ in the mass range of 300-700 GeV, assuming an H with a mass of 200 GeV. The observed limits range from 0.085 pb for an H$^\pm$ mass of 300 GeV to 0.019 pb for a mass of 700 GeV. These are the first limits on H$^\pm$ production in the H$^\pm$ $\to$ HW$^\pm$ decay channel at the LHC.