Search for a Multi-Higgs Boson Cascade in \(W^+W^− b\bar{b}\) events with the ATLAS detector in pp collisions at √s = 8 TeV

Abstract

A search is presented for new particles in an extension to the Standard Model that includes a heavy Higgs boson \(H^0\) , an intermediate charged Higgs boson (H±), and a light Higgs boson \(h^0\) . The analysis searches for events involving the production of a single heavy neutral Higgs boson which decays to the charged Higgs boson and a W boson, where the charged Higgs boson subsequently decays into a W boson and the lightest neutral Higgs boson decaying to a bottom-antibottom-quark pair. Such a cascade results in a W-boson pair and a bottom–antibottom-quark pair in the final state. Events with exactly one lepton, missing transverse momentum, and at least four jets are selected from a data sample corresponding to an integrated luminosity of 20.3 fb\).{-1}\). collected by the ATLAS detector in proton-proton collisions at √s = 8 TeV at the LHC. The data are found to be consistent with Standard Model predictions, and 95% confidence level upper limits are set on the product of cross-section and branching ratio. These limits range from 0.065 pb to 43 pb as a function of \(H^0\) and H± masses, with \(m_{h0}\) fixed at 125 GeV.