A search is presented for decays beyond the standard model of the 125 GeV Higgs bosons to a pair of light bosons, based on models with extended scalar sectors. Light boson masses between 5 and 62.5 GeV are probed in final states containing four tau leptons, two muons and two b quarks, or two muons and two tau leptons. The results are from data in proton-proton collisions corresponding to an integrated luminosity of 19.7 inverse femtobarns, accumulated by the CMS experiment at the LHC at a center-of-mass energy of 8 TeV. No evidence for such exotic decays is found in the data. Upper limits are set on the product of the cross section and branching fraction for several signal processes. The results are also compared to predictions of two-Higgs-doublet models, including those with an additional scalar singlet.
The inclusive cross section for top quark pair production is measured in proton-proton collisions at sqrt(s) = 7 and 8 TeV, corresponding to 5.0 and 19.7 invers-femtobarns, respectively, with the CMS experiment at the LHC. The cross sections are measured in the electron-muon channel using a binned likelihood fit to multi-differential final state distributions related to identified b quark jets and other jets in the event. The measured cross section values are 173.6 +/- 2.1 (stat) +4.5-4.0 (syst) +/- 3.8 (lumi) pb at sqrt(s) = 7 TeV, and 244.9 +/- 1.4 (stat) +6.3-5.5 (syst) +/- 6.4 (lumi) pb at sqrt(s) = 8 TeV, in good agreement with QCD calculations at next-to-next-to-leading-order accuracy. The ratio of the cross sections measured at 7 and 8 TeV is determined, as well as cross sections in the fiducial regions defined by the acceptance requirements on the two charged leptons in the final state. The cross section results are used to determine the top quark pole mass via the dependence of the theoretically predicted cross section on the mass, giving a best result of 173.8 +1.7-1.8 GeV. The data at sqrt(s) = 8 TeV are also used to set limits, for two neutralino mass values, on the pair production of supersymmetric top squarks with masses close to the top quark mass.
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