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Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
[摘要] Results are presented from searches for the standard model Higgs boson in proton–proton collisions at √s = 7 and 8 TeV in the Compact Muon Solenoid experiment at the LHC, using data samples corresponding to integrated luminosities of up to 5.1 fb[superscript −1] at 7 TeV and 5.3 fb[superscript −1] at 8 TeV. The search is performed in five decay modes: γγ, ZZ, W[superscript +]W[superscript −], τ[superscript +]τ[superscript −], and b[bar over b]. An excess of events is observed above the expected background, with a local significance of 5.0 standard deviations, at a mass near 125 GeV, signalling the production of a new particle. The expected significance for a standard model Higgs boson of that mass is 5.8 standard deviations. The excess is most significant in the two decay modes with the best mass resolution, γγ and ZZ; a fit to these signals gives a mass of 125.3 ± 0.4(stat.) ± 0.5(syst.) GeV. The decay to two photons indicates that the new particle is a boson with spin different from one.
[发布日期]  [发布机构] Elsevier
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