Search for narrow high-mass resonances in proton–proton collisions at vs = 8 TeV decaying to a Z and a Higgs boson

Abstract

A search for a narrow, high-mass resonance decaying into Z and Higgs (H) bosons is presented. The final state studied consists of a merged jet pair and a t pair resulting from the decays of Z and H bosons, respectively. The analysis is based on a data sample of proton–proton collisions at a center-of-mass energy of 8 TeV, collected with the CMS experiment in 2012, and corresponding to an integrated luminosity of 19.7 fb-1. In the resonance mass range of interest, which extends from 0.8 to 2.5 TeV, the Z and H bosons are produced with large momenta, which implies that the final products of the two quarks or the two t leptons must be detected within a small angular interval. From a combination of all possible decay modes of the t leptons, production cross sections in a range between 0.9 and 27.8 fb are excluded at 95 % confidence level, depending on the resonance mass.