Search for a light charged Higgs boson in top quark decays in pp collisions at sqrt(s) = 7 TeV

TL;DR

This paper reports a search for a light charged Higgs boson in top quark decays at the LHC, setting upper limits on its branching fraction for masses between 80 and 160 GeV.

Contribution

The study provides the first limits on charged Higgs production in top decays at 7 TeV using CMS data with detailed final state analysis.

Findings

Upper limits on B(t to charged Higgs b) of 2-4%

Charged Higgs masses between 80 and 160 GeV constrained

No evidence found for charged Higgs in analyzed data

Abstract

Results are presented on a search for a light charged Higgs boson that can be produced in the decay of the top quark to charged H and b quark and which, in turn, decays into tau and tau neutrino. The analysed data correspond to an integrated luminosity of about 2 inverse femtobarns recorded in proton-proton collisions at sqrt(s) = 7 TeV by the CMS experiment at the LHC. The search is sensitive to the decays of the top quark pairs t anti-t to charged Higgs W b anti-b and t anti-t to two charged Higgs b anti-b. Various final states have been studied separately, all requiring presence of a tau lepton from charged Higgs decays, missing transverse energy, and multiple jets. Upper limits on the branching fraction B(t to charged Higgs b) in the range of 2-4% are established for charged Higgs boson masses between 80 and 160 GeV, under the assumption that B(charged Higgs to tau anti-tau neutrino) = 1.