A statistical combination of searches for heavy resonances decaying to pairs of bosons or leptons is presented. The data correspond to an integrated luminosity of 35.9 fb$^{-1}$ collected during 2016 by the CMS experiment at the LHC in proton-proton collisions at a center-of-mass energy of 13 TeV. The data are found to be consistent with expectations from the standard model background. Exclusion limits are set in the context of models of spin-1 heavy vector triplets and of spin-2 bulk gravitons. For mass-degenerate W' and Z' resonances that predominantly couple to the standard model gauge bosons, the mass exclusion at 95% confidence level of heavy vector bosons is extended to 4.5 TeV as compared to 3.8 TeV determined from the best individual channel. This excluded mass increases to 5.0 TeV if the resonances couple predominantly to fermions.
A study of the production of prompt J/$\psi$ mesons contained in jets in proton-proton collisions at $\sqrt{s} =$ 8 TeV is presented. The analysis is based on data corresponding to an integrated luminosity of 19.1 fb$^{-1}$ collected with the CMS detector at the LHC. For events with at least one observed jet, the angular separation between the J/$\psi$ meson and the jet is used to test whether the J/$\psi$ meson is part of the jet. The analysis shows that most prompt J/$\psi$ mesons with energy above 15 GeV and rapidity $|y|<$ 1 are contained in jets with pseudorapidity $|\eta_{\text{jet}}|$ $<$ 1. The differential distributions of the probability to have a J/$\psi$ meson contained in a jet as a function of jet energy for a fixed J/$\psi$ energy fraction are compared to a theoretical model using the fragmenting jet function approach. The data agree best with fragmenting jet function calculations that use a long-distance matrix element parameter set in which prompt J/$\psi$ mesons are predicted to be unpolarized. This technique demonstrates a new way to test predictions for prompt J/$\psi$ production using nonrelativistic quantum chromodynamics.
A combination of fifteen top quark mass measurements performed by the ATLAS and CMS experiments at the LHC is presented. The data sets used correspond to an integrated luminosity of up to 5 and 20$^{-1}$ of proton-proton collisions at center-of-mass energies of 7 and 8 TeV, respectively. The combination includes measurements in top quark pair events that exploit both the semileptonic and hadronic decays of the top quark, and a measurement using events enriched in single top quark production via the electroweak $t$-channel. The combination accounts for the correlations between measurements and achieves an improvement in the total uncertainty of 31% relative to the most precise input measurement. The result is $m_\mathrm{t}$ = 172.52 $\pm$ 0.14 (stat) $\pm$ 0.30 (syst) GeV, with a total uncertainty of 0.33 GeV.
A search for the production of Higgs boson pairs in proton-proton collisions at a centre-of-mass energy of 13 TeV is presented, using a data sample corresponding to an integrated luminosity of 35.9 inverse femtobarns collected with the CMS detector at the LHC. Events with one Higgs boson decaying into two bottom quarks and the other decaying into two tau leptons are explored to investigate both resonant and nonresonant production mechanisms. The data are found to be consistent, within uncertainties, with the standard model background predictions. For resonant production, upper limits at the 95% confidence level are set on the production cross section for Higgs boson pairs as a function of the hypothesized resonance mass and are interpreted in the context of the minimal supersymmetric standard model. For nonresonant production, upper limits on the production cross section constrain the parameter space for anomalous Higgs boson couplings. The observed (expected) upper limit at 95% confidence level corresponds to about 30 (25) times the prediction of the standard model.
Upper limits at the 95% CL for nonresonant HH production with anomalous lambda_HHH and yt couplings
Upper limits at the 95% CL for nonresonant HH production with anomalous couplings (shape benchmarks)
Upper limits at the 95% CL for nonresonant HH production with anomalous lambda_HHH and yt couplings, compared for the decay channels investigated
The first observation of top quark production in proton-nucleus collisions is reported using proton-lead data collected by the CMS experiment at the CERN LHC at a nucleon-nucleon center-of-mass energy of sqrt(s[NN]) = 8.16 TeV. The measurement is performed using events with exactly one isolated electron or muon and at least four jets. The data sample corresponds to an integrated luminosity of 174 inverse nanobarns. The significance of the tt-bar signal against the background-only hypothesis is above five standard deviations. The measured cross section is sigma[tt-bar] = 45 +/- 8 nb, consistent with predictions from perturbative quantum chromodynamics.
Invariant mass distributions of the W candidate, $m_{jj'}$, in the 0 b category after all selections. The error bars indicate the statistical uncertainties.
Invariant mass distributions of the W candidate, $m_{jj'}$, in the 1 b category after all selections. The error bars indicate the statistical uncertainties.
Invariant mass distributions of the W candidate, $m_{jj'}$, in the $\geq$2 b category after all selections. The error bars indicate the statistical uncertainties.
This Letter describes a search for Higgs boson pair production using the combined results from four final states: bb$\gamma\gamma$, bb$\tau\tau$, bbbb, and bbVV, where V represents a W or Z boson. The search is performed using data collected in 2016 by the CMS experiment from LHC proton-proton collisions at $\sqrt{s} =$ 13 TeV, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. Limits are set on the Higgs boson pair production cross section. A 95% confidence level observed (expected) upper limit on the nonresonant production cross section is set at 22.2 (12.8) times the standard model value. A search for narrow resonances decaying to Higgs boson pairs is also performed in the mass range 250-3000 GeV. No evidence for a signal is observed, and upper limits are set on the resonance production cross section.
Expected and observed 95\% \CL exclusion limits on the HH production signal strength for the different channels and their combination.
Expected and observed 95\% \CL exclusion limits on the HH production cross section as a function of the k_lambda parameter.
Expected and observed 95\% \CL exclusion limits on the production of a narrow, spin zero resonance (X) decaying into a pair of Higgs bosons.
A measurement of WZ electroweak (EW) vector boson scattering is presented. The measurement is performed in the leptonic decay modes WZ $\to$ $\ell\nu\ell'\ell'$, where $\ell, \ell' = $ e, $\mu$. The analysis is based on a data sample of proton-proton collisions at $\sqrt{s} =$ 13 TeV at the LHC collected with the CMS detector and corresponding to an integrated luminosity of 35.9 fb$^{-1}$. The WZ plus two jet production cross section is measured in fiducial regions with enhanced contributions from EW production and found to be consistent with standard model predictions. The EW WZ production in association with two jets is measured with an observed (expected) significance of 2.2 (2.5) standard deviations. Constraints on charged Higgs boson production and on anomalous quartic gauge couplings in terms of dimension-eight effective field theory operators are also presented.
The measured WZ cross section in the tight EWK fiducial region.
The measured WZ cross section in the loose EWK fiducial region.
The measured EWK WZ scale factor (mu) in the tight EWK fiducial region. The uncertainty is the combined stastical uncertianty and the systematic uncertainty including experimental and theortical sources
Measurements of inclusive isolated-photon and photon+jet production in proton-proton collisions at $\sqrt{s} =$ 13 TeV are presented. The analysis uses data collected by the CMS experiment in 2015, corresponding to an integrated luminosity of 2.26 fb$^{-1}$. The cross section for inclusive isolated photon production is measured as a function of the photon transverse energy in a fiducial region. The cross section for photon+jet production is measured as a function of the photon transverse energy in the same fiducial region with identical photon requirements and with the highest transverse momentum jet. All measurements are in agreement with predictions from next-to-leading-order perturbative QCD.
Double differential cross sections for isolated-photon production in photon rapidity bins. The cross section values are presented per photon transverse energy and rapidity unit.
Tripple differential cross sections for photon+jet production in photon and jet rapidity bins. The cross section values are presented per photon transverse energy, photon rapidity, and jet rapidity unit.
Measurements are presented of W gamma gamma and Z gamma gamma production in proton-proton collisions. Fiducial cross sections are reported based on a data sample corresponding to an integrated luminosity of 19.4 inverse femtobarns collected with the CMS detector at a center-of-mass energy of 8 TeV. Signal is identified through the W to l nu and Z to ll decay modes, where l is a muon or an electron. The production of W gamma gamma and Z gamma gamma, measured with significances of 2.6 and 5.9 standard deviations, respectively, is consistent with standard model predictions. In addition, limits on anomalous quartic gauge couplings in W gamma gamma production are determined in the context of a dimension-8 effective field theory.
Measured fiducial cross section for each channel and for the combination of channels for the WGG and ZGG analyses. The first systematic uncertainty is the combined systematic uncertainty excluding luminosity, the second is the luminosity.
Expected and observed 95% CL limits on anomalous quartic gauge couplings. Limits are obtained using WGG events in which the leading photon pT exceeds 70 GeV.
A search for supersymmetry is presented based on events with at least one photon, jets, and large missing transverse momentum produced in proton-proton collisions at a center-of-mass energy of 13 TeV. The data correspond to an integrated luminosity of 35.9 fb$^{-1}$ and were recorded at the LHC with the CMS detector in 2016. The analysis characterizes signal-like events by categorizing the data into various signal regions based on the number of jets, the number of b-tagged jets, and the missing transverse momentum. No significant excess of events is observed with respect to the expectations from standard model processes. Limits are placed on the gluino and top squark pair production cross sections using several simplified models of supersymmetric particle production with gauge-mediated supersymmetry breaking. Depending on the model and the mass of the next-to-lightest supersymmetric particle, the production of gluinos with masses as large as 2120 GeV and the production of top squarks with masses as large as 1230 GeV are excluded at 95% confidence level.
Observed $95\%$ CL upper limit on the production cross section of gluinos in T5qqqqHG model.
Expected $95\%$ CL upper limit on the production cross section of gluinos in T5qqqqHG model.
Observed $95\%$ CL upper limit on the production cross section of gluinos in T5bbbbZG model.
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