Search for a low-mass pseudoscalar Higgs boson produced in association with a b b-bar pair in pp collisions at sqrt(s) = 8 TeV

TL;DR

This paper reports a search for a low-mass pseudoscalar Higgs boson decaying to tau pairs in proton-proton collisions at 8 TeV, setting limits on its production and excluding certain mass ranges within two-Higgs-doublet models.

Contribution

It provides the first experimental limits on pseudoscalar Higgs bosons in the 25-80 GeV mass range produced with b b-bar pairs at the LHC.

Findings

No evidence for the pseudoscalar boson was observed.

Upper limits on production cross section times branching ratio range from 7 to 39 pb.

Pseudoscalar A bosons with masses between 25 and 80 GeV are excluded in the studied models.

Abstract

A search is reported for a light pseudoscalar Higgs boson decaying to a pair of tau leptons, produced in association with a b b-bar pair, in the context of two-Higgs-doublet models. The results are based on pp collision data at a centre-of-mass energy of 8 TeV collected by the CMS experiment at the LHC and corresponding to an integrated luminosity of 19.7 inverse femtobarns. Pseudoscalar boson masses between 25 and 80 GeV are probed. No evidence for a pseudoscalar boson is found and upper limits are set on the production cross section times branching fraction to tau pairs between 7 and 39 pb at the 95% confidence level. This excludes pseudoscalar A bosons with masses between 25 and 80 GeV, with standard model-like Higgs boson negative couplings to down-type fermions, produced in association with b b-bar pairs, in Type-II, two-Higgs-doublet models.