Constraints on parton distribution functions and extraction of the strong coupling constant from the inclusive jet cross section in pp collisions at √s=7 TeV

Peer reviewe

Study of hadronic event-shape variables in multijet final states in pp collisions at √s=7 TeV

Peer reviewe

Searches for new physics using the t(t)over-bar invariant mass distribution in pp collisions at √s=8 TeV

This is the pre-print version of the final published paper that is available from the link belowSearches for anomalous top quark-antiquark production are presented, based on pp collisions at √s=8  TeV . The data, corresponding to an integrated luminosity of 19:7 fb^-1, were collected with the CMS detector at the LHC. The observed tt invariant mass spectrum is found to be compatible with the standard model prediction. Limits on the production cross section times branching fraction probe, for the first time, a region of parameter space for certain models of new physics not yet constrained by precision measurements

Search for the production of W^{\pm} W^{\pm} W^{\mp} events at \sqrt{s} = 13 TeV

A search for the production of events containing three W bosons predicted by the standard model is reported. The search is based on a data sample of proton-proton collisions at a center-of-mass energy of 13 TeV recorded by the CMS experiment at the CERN LHC and corresponding to a total integrated luminosity of 35.9 fb^{-1}. The search is performed in final states with three leptons (electrons or muons), or with two same-charge leptons plus two jets. The observed (expected) significance of the signal for W^{\pm} W^{\pm} W^{\mp} production is 0.60 (1.78) standard deviations, and the ratio of the measured signal yield to that expected from the standard model is 0.34_{-0.34}^{+0.62}. Limits are placed on three anomalous quartic gauge couplings and on the production of massive axionlike particles

Measurement of prompt J/ψ pair production in pp collisions at√s = 7 Tev

Abstract: Production of prompt J/ψ meson pairs in proton-proton collisions at (formula presented.) = 7 TeV is measured with the CMS experiment at the LHC in a data sample corresponding to an integrated luminosity of about 4.7 fb−1. The two J/ψ mesons are fully reconstructed via their decays into μ+μ− pairs. This observation provides for the first time access to the high-transverse-momentum region of J/ψ pair production where model predictions are not yet established. The total and differential cross sections are measured in a phase space defined by the individual J/ψ transverse momentum (pTJ/ψ) and rapidity (|yJ/ψ|): |yJ/ψ | 6.5 GeV/c; 1.2 4.5 GeV/c. The total cross section, assuming unpolarized prompt J/ψ pair production is 1.49 ± 0.07 (stat) ±0.13 (syst) nb. Different assumptions about the J/ψ polarization imply modifications to the cross section ranging from −31% to +27%

Study of Vector Boson Scattering and Search for New Physics in Events with Two Same-Sign Leptons and Two Jets

A study of vector boson scattering in pp collisions at a center-of-mass energy of 8 TeV is presented. The data sample corresponds to an integrated luminosity of 19.4 fb(-1) collected with the CMS detector. Candidate events are selected with exactly two leptons of the same charge, two jets with large rapidity separation and high dijet mass, and moderate missing transverse energy. The signal region is expected to be dominated by electroweak same-sign W-boson pair production. The observation agrees with the standard model prediction. The observed significance is 2.0 standard deviations, where a significance of 3.1 standard deviations is expected based on the standard model. Cross section measurements for (WW +/-)-W-+/- and WZ processes in the fiducial region are reported. Bounds on the structure of quartic vector-boson interactions are given in the framework of dimension-eight effective field theory operators, as well as limits on the production of doubly charged Higgs bosons

Search for neutral MSSM Higgs bosons decaying to a pair of tau leptons in pp collisions

A search for neutral Higgs bosons in the minimal supersymmetric extension of the standard model (MSSM) decaying to tau-lepton pairs in pp collisions is performed, using events recorded by the CMS experiment at the LHC. The dataset corresponds to an integrated luminosity of 24.6 fb(-1), with 4.9 fb(-1) at 7TeV and 19.7 fb(-1) at 8TeV. To enhance the sensitivity to neutral MSSM Higgs bosons, the search includes the case where the Higgs boson is produced in association with a b-quark jet. No excess is observed in the tau-lepton-pair invariant mass spectrum. Exclusion limits are presented in the MSSM parameter space for different benchmark scenarios, m(h)(max), m(h)(mod+), m(h)(mod-), light-stop, light-stau, T-phobic, and low-m(H). Upper limits on the cross section times branching fraction for gluon fusion and b-quark associated Higgs boson production are also given

Measurement of the Higgs boson width and evidence of its off-shell contributions to ZZ production

Since the discovery of the Higgs boson in 2012, detailed studies of its properties have been ongoing. Besides its mass, its width—related to its lifetime—is an important parameter. One way to determine this quantity is to measure its off-shell production, where the Higgs boson mass is far away from its nominal value, and relating it to its on-shell production, where the mass is close to the nominal value. Here we report evidence for such off-shell contributions to the production cross-section of two Z bosons with data from the CMS experiment at the CERN Large Hadron Collider. We constrain the total rate of the off-shell Higgs boson contribution beyond the Z boson pair production threshold, relative to its standard model expectation, to the interval [0.0061, 2.0] at the 95% confidence level. The scenario with no off-shell contribution is excluded at a p-value of 0.0003 (3.6 standard deviations). We measure the width of the Higgs boson as ΓH=3.2+2.4−1.7MeV, in agreement with the standard model expectation of 4.1 MeV. In addition, we set constraints on anomalous Higgs boson couplings to W and Z boson pairs

Erratum to: Comparison of the Z/γ* + jets to γ + jets cross sections in pp collisions at √s = 8

Erratum to: JHEP10(2015)128. ArXiv ePrint: 1505.06520. The online version of the original article can be found at http://dx.doi.org/10.1007/JHEP10(2015)128