Observation of a Higgs-like Boson in CMS at the LHC

Abstract

After decades of pursuit at lepton and hadron colliders around the world, a Higgs-like boson has been observed at the Large Hadron Collider (LHC). We present results of searches by the CMS collaboration for the production of the standard model Higgs boson in proton-proton collisions, using data samples corresponding to integrated luminosities of 5.1fb−1 at s=7TeV and 5.3fb−1 at s=8TeV. The searches have been performed in five Higgs decay modes, γγ, ZZ, WW, τ+τ−, and bb¯, in the mass range from 110 up to 160 GeV. Multivariate methods have been used in many aspects of the analyses to extract optimal results. An excess of events has been observed above the expected background, with a significance of 5.0 standard deviations. Most of the excess is in the high resolution γγ and ZZ decay modes. A fit to the signal in these modes yields a mass for the boson of 125.3±0.4(stat.)±0.5(syst.) GeV. Since the new boson decays into two photons, its spin can be inferred to be different from one.