Telling the spin of the "Higgs boson" at the LHC

Abstract

We assume that the Higgs boson or a possible resonance---playing its role in strongly interacting models of electroweak symmetry breaking---has been discovered at the LHC and propose a search strategy to determine its spin based on two simple asymmetries in the ZZ, W+W- and t t-bar decays channels. We consider some benchmark values for its mass (in the interval from 182 GeV/c^2 to 1 TeV/c^2) and discuss the relative advantages of the different decay processes. A full analysis, including the background, is given. For a center-of-mass energy of 14 TeV, we find that the lowest integrated luminosity required to discriminate between the different spins is, depending on the process and the resonance mass, between 40 fb^{-1} and 250 fb^{-1}.