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Properties of the Higgs boson with mass near 125 GeV are measured in proton-proton collisions with the CMS experiment at the LHC. Comprehensive sets of production and decay measurements are combined. The decay channels include [gamma][gamma], ZZ, WW, [tau][tau], bb, and [mu][mu] pairs. The data samples were collected in 2011 and 2012 and correspond to integrated luminosities of up to 5.1fb^-1 at 7 TeV and up to 19.7 fb^-1 at 8 TeV. From the high-resolution [gamma][gamma] and ZZ channels, the mass of the Higgs boson is determined to be 125.02^+0.26_-0.27(stat)^+0.14_-0.15(syst)GeV. For this mass value, the event yields obtained in the different analyses tagging specific decay channels and production mechanisms are consistent with those expected for the standard model Higgs boson. The combined best-fit signal relative to the standard model expectation is 1.00 +/- 0.09(stat)^+0.08_-0.07(theo) +/- 0.07(syst) at the measured mass. The couplings of the Higgs boson are probed for deviations in magnitude from the standard model predictions in multiple ways, including searches for invisible and undetected decays. No significant deviations are found.

Observation of the diphoton decay mode of the recently discovered Higgs boson and measurement of some of its properties are reported. The analysis uses the entire dataset collected by the CMS experiment in proton-proton collisions during the 2011 and 2012 LHC running periods. The data samples correspond to integrated luminosities of 5.1 fb -1 at s = 7 TeV and 19.7 fb -1 at 8 TeV  . A clear signal is observed in the diphoton channel at a mass close to 125 GeV  with a local significance of 5.7 σ , where a significance of 5.2 σ is expected for the standard model Higgs boson. The mass is measured to be 124.70 ± 0.34 GeV = 124.70 ± 0.31 (stat) ± 0.15 (syst) GeV , and the best-fit signal strength relative to the standard model prediction is 1 . 14 - 0.23 + 0.26 = 1.14 ± 0.21 (stat) - 0.05 + 0.09 (syst) - 0.09 + 0.13 (theo) . Additional measurements include the signal strength modifiers associated with different production mechanisms, and hypothesis tests between spin-0 and spin-2 models.

Results are presented from a search for particle dark matter (DM), extra dimensions, and unparticles using events containing a jet and an imbalance in transverse momentum. The data were collected by the CMS detector in proton–proton collisions at the LHC and correspond to an integrated luminosity of 19.7 fb -1 at a centre-of-mass energy of 8 TeV . The number of observed events is found to be consistent with the standard model prediction. Limits are placed on the DM-nucleon scattering cross section as a function of the DM particle mass for spin-dependent and spin-independent interactions. Limits are also placed on the scale parameter M D in the Arkani-Hamed, Dimopoulos, and Dvali (ADD) model of large extra dimensions, and on the unparticle model parameter Λ U . The constraints on ADD models and unparticles are the most stringent limits in this channel and those on the DM-nucleon scattering cross section are an improvement over previous collider results.

A bstract A search for a standard model Higgs boson decaying into a pair of τ leptons is performed using events recorded by the CMS experiment at the LHC in 2011 and 2012. The dataset corresponds to an integrated luminosity of 4.9 fb −1 at a centre-of-mass energy of 7 TeV and 19.7 fb −1 at 8 TeV. Each τ lepton decays hadronically or leptonically to an electron or a muon, leading to six different final states for the τ -lepton pair, all considered in this analysis. An excess of events is observed over the expected background contributions, with a local significance larger than 3 standard deviations for m H values between 115 and 130 GeV. The best fit of the observed H → τ τ signal cross section times branching fraction for m H = 125 GeV is 0 . 78 ± 0 . 27 times the standard model expectation. These observations constitute evidence for the 125 GeV Higgs boson decaying to a pair of τ leptons.

Searches for the direct electroweak production of supersymmetric charginos, neutralinos, and sleptons in a variety of signatures with leptons and W , Z , and Higgs bosons are presented. Results are based on a sample of proton-proton collision data collected at center-of-mass energy s = 8 TeV with the CMS detector in 2012, corresponding to an integrated luminosity of 19.5  fb -1 . The observed event rates are in agreement with expectations from the standard model. These results probe charginos and neutralinos with masses up to 720  GeV , and sleptons up to 260  GeV , depending on the model details.

A bstract A search for the standard model Higgs boson decaying to a W-boson pair at the LHC is reported. The event sample corresponds to an integrated luminosity of 4.9 fb −1 and 19.4 fb −1 collected with the CMS detector in pp collisions at = 7 and 8 TeV, respectively. The Higgs boson candidates are selected in events with two or three charged leptons. An excess of events above background is observed, consistent with the expectation from the standard model Higgs boson with a mass of around 125 GeV. The probability to observe an excess equal or larger than the one seen, under the background-only hypothesis, corresponds to a significance of 4.3 standard deviations for m H = 125.6 GeV. The observed signal cross section times the branching fraction to WW for m H = 125.6 GeV is times the standard model expectation. The spin-parity J P = 0 + hypothesis is favored against a narrow resonance with J P = 2 + or J P = 0 − that decays to a W-boson pair. This result provides strong evidence for a Higgs-like boson decaying to a W-boson pair.

The normalized differential cross section for top quark pair ( t t ¯ ) production is measured in pp collisions at a centre-of-mass energy of 8 TeV at the CERN LHC using the CMS detector in data corresponding to an integrated luminosity of 19.7 fb - 1 . The measurements are performed in the lepton + jets ( e / μ + jets) and in the dilepton ( e + e - , μ + μ - , and e ± μ ∓ ) decay channels. The t t ¯ cross section is measured as a function of the kinematic properties of the charged leptons, the jets associated to b quarks, the top quarks, and the t t ¯ system. The data are compared with several predictions from perturbative quantum chromodynamic up to approximate next-to-next-to-leading-order precision. No significant deviations are observed relative to the standard model predictions.

A bstract Dimuon and dielectron mass spectra, obtained from data resulting from proton-proton collisions at 8 TeV and recorded by the CMS experiment, are used to search for both narrow resonances and broad deviations from standard model predictions. The data correspond to an integrated luminosity of 20.6 (19.7) fb −1 for the dimuon (dielectron) channel. No evidence for non-standard-model physics is observed and 95% confidence level limits are set on parameters from a number of new physics models. The narrow resonance analyses exclude a Sequential Standard Model Z SSM ′ resonance lighter than 2.90 TeV, a superstring-inspired Z ψ ′ lighter than 2.57 TeV, and Randall-Sundrum Kaluza-Klein gravitons with masses below 2.73, 2.35, and 1.27 TeV for couplings of 0.10, 0.05, and 0.01, respectively. A notable feature is that the limits have been calculated in a model-independent way to enable straightforward reinterpretation in any model predicting a resonance structure. The observed events are also interpreted within the framework of two non-resonant analyses: one based on a large extra dimensions model and one based on a quark and lepton compositeness model with a left-left isoscalar contact interaction. Lower limits are established on M S , the scale characterizing the onset of quantum gravity, which range from 4.9 to 3.3 TeV, where the number of additional spatial dimensions varies from 3 to 7. Similarly, lower limits on Λ, the energy scale parameter for the contact interaction, are found to be 12.0 (15.2) TeV for destructive (constructive) interference in the dimuon channel and 13.5 (18.3) TeV in the dielectron channel.

(ProQuest: ... denotes formulae and/or non-USASCII text omitted; see image) This paper presents a search for the pair production of top squarks in events with a single isolated electron or muon, jets, large missing transverse momentum, and large transverse mass. The data sample corresponds to an integrated luminosity of 19.5 fb^sup -1^ of pp collisions collected in 2012 by the CMS experiment at the LHC at a center-of-mass energy of ... No significant excess in data is observed above the expectation from standard model processes. The results are interpreted in the context of supersymmetric models with pair production of top squarks that decay either to a top quark and a neutralino or to a bottom quark and a chargino. For small mass values of the lightest supersymmetric particle, top-squark mass values up to around 650 GeV are excluded.