A combination is presented of the inclusive deep inelastic cross sections measured by the H1 and ZEUS Collaborations in neutral and charged current unpolarised e ± p scattering at HERA during the period 1994-2000. The data span six orders of magnitude in negative four-momentum-transfer squared, Q 2 , and in Bjorken x. The combination method used takes the correlations of systematic uncertainties into account, resulting in an improved accuracy. The combined data are the sole input in a NLO QCD analysis which determines a new set of parton distributions, HERAPDF1.0, with small experimental uncertainties. This set includes an estimate of the model and parametrisation uncertainties of the fit result.

A description is provided of the software algorithms developed for the CMS tracker both for reconstructing charged-particle trajectories in proton-proton interactions and for using the resulting tracks to estimate the positions of the LHC luminous region and individual primary-interaction vertices. Despite the very hostile environment at the LHC, the performance obtained with these algorithms is found to be excellent. For tt events under typical 2011 pileup conditions, the average trackreconstruction efficiency for promptly-produced charged particles with transverse momenta of p T > 0.9 GeV is 94% for pseudorapidities of |η| < 0.9 and 85% for 0.9 < |η| < 2.5. The inefficiency is caused mainly by hadrons that undergo nuclear interactions in the tracker material. For isolated muons, the corresponding efficiencies are essentially 100%. For isolated muons of p T = 100 GeV emitted at |η| < 1.4, the resolutions are approximately 2.8% in p T , and respectively, 10 µm and 30 µm in the transverse and longitudinal impact parameters. The position resolution achieved for reconstructed primary vertices that correspond to interesting pp collisions is 10-12 µm in each of the three spatial dimensions. The tracking and vertexing software is fast and flexible, and easily adaptable to other functions, such as fast tracking for the trigger, or dedicated tracking for electrons that takes into account bremsstrahlung.

Properties of the Higgs boson with mass near 125 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 , , , , , and pairs. The data samples were collected in 2011 and 2012 and correspond to integrated luminosities of up to 5.1 at 7 and up to 19.7 at 8. From the high-resolution and channels, the mass of the Higgs boson is determined to be . 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 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.

Combined measurements of the production and decay rates of the Higgs boson, as well as its couplings to vector bosons and fermions, are presented. The analysis uses the LHC proton–proton collision data set recorded with the CMS detector in 2016 at , corresponding to an integrated luminosity of 35.9 . The combination is based on analyses targeting the five main Higgs boson production mechanisms (gluon fusion, vector boson fusion, and associated production with a or boson, or a top quark-antiquark pair) and the following decay modes: , , , , , and . Searches for invisible Higgs boson decays are also considered. The best-fit ratio of the signal yield to the standard model expectation is measured to be , assuming a Higgs boson mass of . Additional results are given for various assumptions on the scaling behavior of the production and decay modes, including generic parametrizations based on ratios of cross sections and branching fractions or couplings. The results are compatible with the standard model predictions in all parametrizations considered. In addition, constraints are placed on various two Higgs doublet models.

A detailed description is reported of the analysis used by the CMS Collaboration in the search for the standard model Higgs boson in pp collisions at the LHC, which led to the observation of a new boson. The data sample corresponds to integrated luminosities up to 5.1 fb −1 at √ s = 7 TeV, and up to 5.3 fb −1 at √ s = 8 TeV. The results for five Higgs boson decay modes γγ, ZZ, WW, τ τ , and bb, which show a combined local significance of 5 standard deviations near 125 GeV, are reviewed. A fit to the invariant mass of the two high resolution channels, γγ and ZZ → 4 , gives a mass estimate of 125.3 ± 0.4 (stat.) ± 0.5 (syst.) GeV. The measurements are interpreted in the context of the standard model Lagrangian for the scalar Higgs field interacting with fermions and vector bosons. The measured values of the corresponding couplings are compared to the standard model predictions. The hypothesis of custodial symmetry is tested through the measurement of the ratio of the couplings to the W and Z bosons. All the results are consistent, within their uncertainties, with the expectations for a standard model Higgs boson. The CMS collaboration 106 Keywords: Hadron-Hadron Scattering IntroductionThe standard model (SM) [1-3] of particle physics accurately describes many experimental results that probe elementary particles and their interactions up to an energy scale of a few hundred GeV [4]. In the SM, the building blocks of matter, the fermions, are comprised of quarks and leptons. The interactions are mediated through the exchange of force carriers: the photon for electromagnetic interactions, the W and Z bosons for weak interactions, and the gluons for strong interactions. All the elementary particles acquire mass through their interaction with the Higgs field [5][6][7][8][9][10][11][12][13]. This mechanism, called the "Higgs" or "BEH" mechanism [5][6][7][8][9][10], is the first coherent and the simplest solution for giving mass to W and Z bosons, while still preserving the symmetry of the Lagrangian. It is realized by introducing a new complex scalar field into the model. By construction, this field allows the W and Z bosons to acquire mass whilst the photon remains massless, and adds to the model one new scalar particle, the SM Higgs boson (H). The Higgs scalar field and its conjugate can also give mass to the fermions, through Yukawa interactions [11][12][13] The discovery or exclusion of the SM Higgs boson is one of the primary scientific goals of the LHC. Previous direct searches at the LHC were based on data from protonproton collisions corresponding to an integrated luminosity of 5.1 fb −1 collected at a centreof-mass energy of 7 TeV. The CMS experiment excluded at 95% CL masses from 127 to 600 GeV [20]. The ATLAS experiment excluded at 95% CL the ranges 111. . Within the remaining allowed mass region, an excess of events between 2 and 3 standard deviations (σ) near 125 GeV was reported by both experiments. In 2012, the proton-proton centre-of-mass energy was increased to 8 TeV, and by the end of June, an...