Four-lepton production in proton-proton collisions, pp to (Z/gamma*)(Z/gamma*) to l+l-l'+l'-, where l, l' = e or mu, is studied at a center-of-mass energy of 13 TeV with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 2.6 inverse femtobarns. The ZZ production cross section, sigma(pp to ZZ) = 14.6 +1.9/-1.8 (stat) +0.5/-0.3 (syst) +/- 0.2 (theo) +/- 0.4 (lumi) pb, is measured for events with two opposite-sign, same-flavor lepton pairs produced in the mass region 60 < m[l+l-], m[l'+l'-] < 120 GeV. The Z boson branching fraction to four leptons is measured to be B(Z to l+l-l'+l'-) = 4.9 +0.8/-0.7 (stat) +0.3/-0.2 (syst) +0.2/-0.1 (theo) +/- 0.1 (lumi) x E-6 for the four-lepton invariant mass in the range 80 < m[l+l-l'+l'-] < 100 GeV and dilepton mass m[l+l-] > 4 GeV for all opposite-sign, same-flavor lepton pairs. The results are in agreement with standard model predictions.
The (P P to Z Z to l+l-l'+l'-) fiducial cross section. The first systematic uncertainty is detector systematics, the second is luminosity uncertainty. The theoretical prediction is POWHEG generated at NLO plus the gluon-gluon initial state contribution from MCFM, using NNPDF3.0 PDFs and scales mu_F = mu_R = 0.5m[l+l-l'+l'-].
The (P P to Z to l+l-l'+l'-) fiducial cross section. The first systematic uncertainty is detector systematics, the second is luminosity uncertainty. The theoretical prediction is POWHEG generated at NLO using NNPDF3.0 PDFs and scales mu_F = mu_R = m[l+l-l'+l'-].
The total (P P to Z) cross section times the (Z to l+l-l'+l'-) branching ratio. The first systematic uncertainty is detector systematics, the second is theoretical uncertainty, and the third is luminosity uncertainty.
The cross section of top quark-antiquark pair production in proton-proton collisions at sqrt(s) = 13 TeV is measured by the CMS experiment at the LHC, using data corresponding to an integrated luminosity of 2.2 inverse femtobarns. The measurement is performed by analyzing events in which the final state includes one electron, one muon, and two or more jets, at least one of which is identified as originating from hadronization of a b quark. The measured cross section is 815 +/- 9 (stat) +/- 38 (syst) +/- 19 (lumi) pb, in agreement with the expectation from the standard model.
Summary of the individual contributions to the uncertainty in the $\sigma_{t\bar{t}}$ measurement.
Measurement of the $t\bar{t}$ production cross-section in $pp$ collisions at $\sqrt{s} = 13$ TeV.
Number of dilepton events obtained after applying the full selection. The results are given for the individual sources of background, $t\bar{t}$ signal with a top quark mass of 172.5 GeV and $\sigma_{t\bar{t}}$ = 832 +/- 46 pb, and data. The uncertainties correspond to statistical and systematic components.
The WZ production cross section in proton-proton collisions at sqrt(s) = 13 TeV is measured with the CMS experiment at the LHC using a data sample corresponding to an integrated luminosity of 2.3 inverse femtobarns. The measurement is performed in the leptonic decay modes WZ to l nu l' l', where l, l'= e, mu. The measured cross section for the range 60 < m[l'l'] < 120 GeV is sigma(pp to WZ) = 39.9 +/- 3.2 (stat) +2.9/-3.1 (syst) +/- 0.4 (theo) +/- 1.3 (lumi) pb, consistent with the standard model prediction.
The fiducial pp to WZ to lnul'l' cross section. The first systematic uncertainty is detector systematics and the second is luminosity uncertainty. The theoretical prediction is calculated with MCFM at NLO with NNPDF3.0 PDFs, with dynamic renormalization and factorization scales set to muR = muF = m[WZ]. The uncertainty is obtained by varying the factorization and renormalization scales independently up and down by a factor of two with the condition that 0.5 < muR/muF < 2.
The total pp to WZ cross section. The first systematic uncertainty is detector systematics and the second is luminosity uncertainty. The first theoretical prediction is calculated with MCFM at NLO with NNPDF3.0 PDFs, with dynamic renormalization and factorization scales set to muR = muF = m[WZ]. The second theoretical prediction is calculated with MATRIX at NNLO with fixed QCD scales set to muR = muF = 1/2 (m[Z] + m[W]) and with NNPDF3.0 PDFs. The uncertainty is obtained by varying the factorization and renormalization scales independently up and down by a factor of two with the condition that 0.5 < muR/muF < 2.
The top quark pair production cross section is measured for the first time in proton-proton collisions at sqrt(s) = 13 TeV by the CMS experiment at the CERN LHC, using data corresponding to an integrated luminosity of 43 inverse picobarns. The measurement is performed by analyzing events with at least one electron and one muon of opposite charge, and at least two jets. The measured cross section is 746 +/- 58 (stat) +/- 53 (syst) +/- 36 (lumi) pb, in agreement with the expectation from the standard model.
The first measurement of the $t\bar{t}$ production cross-section in $pp$ collisions at $\sqrt{s} = 13$ TeV.
A measurement is presented of the associated production of a single top quark and a Z boson. The study uses data from proton-proton collisions at $\sqrt{s} =$ 13 TeV recorded by the CMS experiment, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. Using final states with three leptons (electrons or muons), the tZq production cross section is measured to be $\sigma$(pp$\to$tZq$\to$Wb$\ell^+\ell^-$q) = $123 ^{+33}_{-31}$ (stat) $^{+29}_{-23}$ (syst) fb, where $\ell$ stands for electrons, muons, or $\tau$ leptons, with observed and expected significances of 3.7 and 3.1 standard deviations, respectively.
The measured cross section, with statistical and systematic uncertainties. The observed significance. The expected significance
A search is presented for additional neutral Higgs bosons in the $\tau\tau$ final state in proton-proton collisions at the LHC. The search is performed in the context of the minimal supersymmetric extension of the standard model (MSSM), using the data collected with the CMS detector in 2016 at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. To enhance the sensitivity to neutral MSSM Higgs bosons, the search includes production of the Higgs boson in association with b quarks. No significant deviation above the expected background is observed. Model-independent limits at 95% confidence level (CL) are set on the product of the branching fraction for the decay into $\tau$ leptons and the cross section for the production via gluon fusion or in association with b quarks. These limits range from 18 pb at 90 GeV to 3.5 fb at 3.2 TeV for gluon fusion and from 15 pb (at 90 GeV) to 2.5 fb (at 3.2 TeV) for production in association with b quarks, assuming a narrow width resonance. In the m$_{\text{h}}^{\text{mod+}}$ scenario these limits translate into a 95% CL exclusion of $\tan\beta>$ 6 for neutral Higgs boson masses below 250 GeV, where $\tan\beta$ is the ratio of the vacuum expectation values of the neutral components of the two Higgs doublets. The 95% CL exclusion contour reaches 1.6 TeV for $\tan\beta=$ 60.
Expected and observed 95% CL upper limits for the production of a single narrow resonance, $\phi$, with a mass between 90 GeV and 3.2 TeV via gluon-gluon fusion. This limit database corresponds to the values shown in Figure 7a of the paper.
Expected and observed 95% CL upper limits for the production of a single narrow resonance, $\phi$, with a mass between 90 GeV and 3.2 TeV in association with b-quarks. This limit database corresponds to the values shown in Figure 7b of the paper.
Scan of the likelihood function for the search in the $\tau\tau$ final state for a single narrow resonance, $\phi$, produced via gluon fusion ($gg\phi$) or in association with b quarks ($bb\phi$). The scan is performed in 40000 points of the ($\sigma(gg\phi)\cdot B(\phi\rightarrow\tau\tau)$, $\sigma(bb\phi)\cdot B(\phi\rightarrow\tau\tau)$) plane. An asimov dataset constructed from the expectation of all backgrounds and the SM Higgs boson is tested against a background hypothesis including the SM Higgs boson. For further details and instructions, please have a look into the following README file http://cms-results.web.cern.ch/cms-results/public-results/publications/HIG-17-020/2D-likelihood-scans/README.txt. Selected examples of such a likelihood scan are given in Figure 8 of the paper.
A measurement of the differential cross sections for a W boson produced in association with jets in the muon decay channel is presented. The measurement is based on 13 TeV proton-proton collision data corresponding to an integrated luminosity of 2.2 inverse femtobarns, recorded by the CMS detector at the LHC. The cross sections are reported as functions of jet multiplicity, jet transverse momentum pT, jet rapidity, the scalar pT sum of the jets, and angular correlations between the muon and the jet for different jet multiplicities. The measured cross sections are in agreement with predictions that include multileg leading-order (LO) and next-to-LO matrix element calculations interfaced with parton showers, as well as a next-to-next-to-LO calculation for the W boson and one jet production.
The cross section measurement as a function of the exclusive jet multiplicity, for jet multiplicities of up to 6.
The cross section measurement as a function of the inclusive jet multiplicity, for jet multiplicities of up to 6.
The differential cross section measurement as a function of the transverse momentum of the first leading jet.
Four-lepton production in proton-proton collisions, $\mathrm{pp}\to (\mathrm{Z}/ \gamma^*)(\mathrm{Z}/\gamma^*) \to 4\ell$, where $\ell = \mathrm{e}$ or $\mu$, is studied at a center-of-mass energy of 13 TeV with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 35.9 fb$^{-1}$. The ZZ production cross section, $\sigma(\mathrm{pp} \to \mathrm{Z}\mathrm{Z}) = 17.2 \pm 0.5\text{ (stat) }\pm 0.7\text{ (syst) }\pm 0.4(\mathrm{theo}) \pm 0.4\text{ (lumi)}$ pb, measured using events with two opposite-sign, same-flavor lepton pairs produced in the mass region $60 < m_{\ell^+\ell^-} < $120 GeV, is consistent with standard model predictions. Differential cross sections are measured and are well described by the theoretical predictions. The Z boson branching fraction to four leptons is measured to be $\mathcal{B}(\mathrm{Z}\to 4\ell) = 4.8 \pm 0.2\text{ (stat) }\pm 0.2\text{ (syst) } \pm 0.1\text{ (theo) }\pm 0.1\text{ (lumi) }\times 10^{-6}$ for events with a four-lepton invariant mass in the range 80 $ < m_{4\ell} < $ 100 GeV and a dilepton mass $m_{\ell\ell} > $4 GeV for all opposite-sign, same-flavor lepton pairs. The results agree with standard model predictions. The invariant mass distribution of the four-lepton system is used to set limits on anomalous ZZZ and ZZ$\gamma$ couplings at 95% confidence level: $-0.0012 < f_4^\mathrm{Z} < 0.0010$, $-0.0010 < f_5^\mathrm{Z} < 0.0013$, $-0.0012 < f_4^{\gamma} < 0.0013$, $-0.0012 < f_5^{\gamma} < 0.0013$.
The measured total ZZ cross section using 2016 data. The first systematic uncertainty is the combined systematic uncertainty excluding luminosity and theortical sources, the second is theoretical uncertianty on the extrapolation from the selected region to the total phase space, the third is the luminosity uncertianty
The measured total ZZ cross section using 2015 and 2016. The first systematic uncertainty is the combined systematic uncertainty excluding luminosity and theortical sources, the second is theoretical uncertianty on the extrapolation from the selected region to the total phase space, the third is the luminosity uncertianty
The measured fiducial ZZ cross sections. The first systematic uncertainty is the combined systematic uncertainty excluding luminosity, the second is the luminosity uncertianty
A measurement of the inelastic proton-proton cross section with the CMS detector at a center-of-mass energy of $\sqrt{s} =$ 13 TeV is presented. The analysis is based on events with energy deposits in the forward calorimeters, which cover pseudorapidities of -6.6 $< \eta $ 4.1 GeV and/or $M_\mathrm{Y} >$ 13 GeV, where $M_\mathrm{X}$ and $M_\mathrm{Y}$ are the masses of the diffractive dissociation systems at negative and positive pseudorapidities, respectively. The results are compared with those from other experiments as well as to predictions from high-energy hadron-hadron interaction models.
The measured fiducial cross sections. The first bin represents the $\xi > 10^{-6}$ region, while the second bin represents the extended $\xi_{X} > 10^{-7}$ or $\xi_{Y} > 10^{-6}$ result. The first uncertainty is the systematic uncertainty excluding luminosity, the second is the luminosity uncertainty.
A search for the pair production of heavy fermionic partners of the top quark with charge 5/3 (X$_{5/3}$) is performed in proton-proton collisions at a center-of-mass energy of 13 TeV with the CMS detector at the CERN LHC. The data sample analyzed corresponds to an integrated luminosity of 35.9 fb$^{-1}$. The X$_{5/3}$ quark is assumed always to decay into a top quark and a W boson. Both the right-handed and left-handed X$_{5/3}$ couplings to the W boson are considered. Final states with either a pair of same-sign leptons or a single lepton are studied. No significant excess of events is observed above the expected standard model background. Lower limits at 95% confidence level on the X$_{5/3}$ quark mass are set at 1.33 and 1.30 TeV respectively for the case of right-handed and left-handed couplings to W bosons in a combination of the same-sign dilepton and single-lepton final states.
Summary of yields from simulated prompt same-sign dilepton (SSP MC), same-sign nonprompt (Nonprompt), and opposite-sign prompt (ChargeMisID) backgrounds after the full analysis selection. Also shown are the number of expected events for an RH $X_{5/3}$ particle with a mass of 1 TeV. The uncertainties include both statistical and all systematic components (as described in Section 8). The number of events and uncertainties correspond to the background- only fit to data for the background, while for the signal they are based on the yields before the fit to data.
Distributions of $\min[M(\ell,\mathrm{b})]$ in the $\mathrm{t\overline{t}}$ control region, for 1 b-tagged jet category. Example signal distributions are also shown. The background distributions correspond to background-only fit to data while signal distributions are before the fit to data. Electron and muon event samples are combined. The last bin includes overflow events and its content is divided by the bin width. The distributions in each category have variable-size bins, chosen so that the statistical uncertainty in the total background in each bin is less than 30%. The lower panel in each plot shows the difference between the observed and the predicted numbers of events in that bin divided by the total uncertainty. The total uncertainty is calculated as the sum in quadrature of the statistical uncertainty in the observed measurement and the statistical and systematic uncertainties in the background-only fit to data.
Distributions of $\min[M(\ell,\mathrm{b})]$ in the $\mathrm{t\overline{t}}$ control region, for 2 or more b-tagged jet category. Example signal distributions are also shown. The background distributions correspond to background-only fit to data while signal distributions are before the fit to data. Electron and muon event samples are combined. The last bin includes overflow events and its content is divided by the bin width. The distributions in each category have variable-size bins, chosen so that the statistical uncertainty in the total background in each bin is less than 30%. The lower panel in each plot shows the difference between the observed and the predicted numbers of events in that bin divided by the total uncertainty. The total uncertainty is calculated as the sum in quadrature of the statistical uncertainty in the observed measurement and the statistical and systematic uncertainties in the background-only fit to data.
A search for a new heavy particle decaying to a pair of vector bosons (WW or WZ) is presented using data from the CMS detector corresponding to an integrated luminosity of 35.9 fb$^{-1}$ collected in proton-proton collisions at a centre-of-mass energy of 13 TeV in 2016. One of the bosons is required to be a W boson decaying to e$\nu$ or $\mu\nu$, while the other boson is required to be reconstructed as a single massive jet with substructure compatible with that of a highly-energetic quark pair from a W or Z boson decay. The search is performed in the resonance mass range between 1.0 and 4.5 TeV. The largest deviation from the background-only hypothesis is observed for a mass near 1.4 TeV and corresponds to a local significance of 2.5 standard deviations. The result is interpreted as an upper bound on the resonance production cross section. Comparing the excluded cross section values and the expectations from theoretical calculations in the bulk graviton and heavy vector triplet models, spin-2 WW resonances with mass smaller than 1.07 TeV and spin-1 WZ resonances lighter than 3.05 TeV, respectively, are excluded at 95% confidence level.
Exclusion limits on the product of the production cross section and the branching fraction for a new spin-2 resonance decaying to WW, as a function of the resonance mass hypothesis.
Exclusion limits on the product of the production cross section and the branching fraction for a new spin-1 resonance decaying to WZ, as a function of the resonance mass hypothesis.
Signal selection efficiency times acceptance as a function of resonance mass for a spin-2 bulk graviton decaying to WW and a spin-1 W' decaying to WZ.
Differential production cross sections of J/$\psi$ and $\psi$(2S) charmonium and $\Upsilon$(nS) (n = 1, 2, 3) bottomonium states are measured in proton-proton collisions at $\sqrt{s} =$ 13 TeV, with data collected by the CMS detector at the LHC, corresponding to an integrated luminosity of 2.3 fb$^{-1}$ for the J/$\psi$ and 2.7 fb$^{-1}$ for the other mesons. The five quarkonium states are reconstructed in the dimuon decay channel, for dimuon rapidity $|y| <$ 1.2. The double-differential cross sections for each state are measured as a function of $y$ and transverse momentum, and compared to theoretical expectations. In addition, ratios are presented of cross sections for prompt $\psi$(2S) to J/$\psi$, $\Upsilon$(2S) to $\Upsilon$(1S), and $\Upsilon$(3S) to $\Upsilon$(1S) production.
Double-differential cross section times the dimuon branching fraction of the J/psi meson for different ranges of pT in bins of |y| and for the full |y| < 1.2 range, for the unpolarized decay hypothesis. The global uncertainty in the integrated luminosity of 2.3% is not included in the systematic uncertainties.
Double-differential cross section times the dimuon branching fraction of the psi(2S) meson for different ranges of pT in bins of |y| and for the full |y| < 1.2 range, for the unpolarized decay hypothesis. The global uncertainty in the integrated luminosity of 2.3% is not included in the systematic uncertainties.
Double-differential cross section times the dimuon branching fraction of the Y(1S) meson for different ranges of pT in bins of |y| and for the full |y| < 1.2 range, for the unpolarized decay hypothesis. The global uncertainty in the integrated luminosity of 2.3% is not included in the systematic uncertainties.
A search for Higgs bosons that decay into a bottom quark-antiquark pair and are accompanied by at least one additional bottom quark is performed with the CMS detector. The data analyzed were recorded in proton-proton collisions at a centre-of-mass energy of $\sqrt{s} =$ 13 TeV at the LHC, corresponding to an integrated luminosity of 35.7 fb$^{-1}$. The final state considered in this analysis is particularly sensitive to signatures of a Higgs sector beyond the standard model, as predicted in the generic class of two Higgs doublet models (2HDMs). No signal above the standard model background expectation is observed. Stringent upper limits on the cross section times branching fraction are set for Higgs bosons with masses up to 1300 GeV. The results are interpreted within several MSSM and 2HDM scenarios.
Expected and observed 95% CL upper limits on sigma(pp->b+H(MSSM)+X) * B(H(MSSM) -> bb) in pb as a function of m(H(MSSM)), where H(MSSM) denotes a heavy Higgs-like state like the H and A bosons of MSSM and 2HDM, as obtained from the 13 TeV data.
Expected and observed 95% CL upper limits on tan(beta) as a function of m(A) in the mhmodp benchmark scenario for a higgsino mass parameter of mu=+200 GeV. Since theoretical predictions are not reliable for tan(beta)>60, entries for which tan(beta) would exceed this value are indicated by N/A.
Expected and observed 95% CL upper limits on tan(beta) as a function of m(A) in the hMSSM benchmark scenario. Since theoretical predictions are not reliable for tan(beta)>60, entries for which tan(beta) would exceed this value are indicated by N/A.
The differential cross sections for inclusive production of B+ hadrons are measured as a function of the B+ transverse momentum pT[B] and rapidity y[B] in pp collisions at a centre-of-mass energy of 13 TeV, using data collected by the CMS experiment that correspond to an integrated luminosity of 49.4 inverse picobarns. The measurement uses the exclusive decay channel B+ to J/psi K+, with J/psi mesons that decay to a pair of muons. The results show a reasonable agreement with theoretical calculations within the uncertainties.
B+ differential production cross sections DSIG/DPT for |yB|< 1.45 or |yB|< 2.1, at 13 TeV. The calculations from FONLL and PYTHIA are provided. The ratio of the data at 13 TeV to the FONLL predictions and the ratios of the PYTHIA to the FONLL calculations are also given.
B+ differential production cross sections DSIG/DETARAP for 10 < ptB < 100 GeV or 17 < ptB < 100 GeV, at 13 TeV. The calculations from FONLL and PYTHIA are provided. The ratio of the data at 13 TeV to the FONLL predictions and the ratios of the PYTHIA to the FONLL calculations are also given.
Ratios of B+ differential production cross sections at 13 TeV and at 7 TeV as a function of ptB for |yB|< 1.45 or |yB|< 2.1. The calculations from FONLL and PYTHIA are provided as well.
The cross section of top quark pair production is measured in the $\mathrm{t\bar{t}}\to (\ell\nu_{\ell})(\tau_\mathrm{h}\nu_{\tau})\mathrm{b\bar{b}}$ final state, where $\tau_\mathrm{h}$ refers to the hadronic decays of the $\tau$ lepton, and $\ell$ is either an electron or a muon. The data sample corresponds to an integrated luminosity of 35.9 fb$^{-1}$ collected in proton-proton collisions at $\sqrt{s}=$ 13 TeV with the CMS detector. The measured cross section is $\sigma_{\mathrm{t\bar{t}}} =$ 781 $\pm$ 7 (stat) $\pm$ 62 (syst) $\pm$ 20 (lum) pb, and the ratio of the partial width $\Gamma($t$\to\tau\nu_{\tau}$b) to the total decay width of the top quark is measured to be 0.1050 $\pm$ 0.0009 (stat) $\pm$ 0.0071 (syst). This is the first measurement of the $\mathrm{t\bar{t}}$ production cross section in proton-proton collisions at $\sqrt{s}=$ 13 TeV that explicitly includes $\tau$ leptons. The ratio of the cross sections in the $\ell\tau_\mathrm{h}$ and $\ell\ell$ final states yields a value $R_{\ell\tau_\mathrm{h}/\ell\ell}=$ 0.973 $\pm$ 0.009 (stat) $\pm$ 0.066 (syst), consistent with lepton universality.
The measured inclusive top quark pair production cross section in the dilepton final state with one tau lepton.
The ratio between top quark production cross sections measured in lepton-tau and light dilepton final states.
The ratio of the partial width to the total decay width of the top quark.
A search for exotic decays of the Higgs boson to a pair of light pseudoscalar particles a$_1$ is performed under the hypothesis that one of the pseudoscalars decays to a pair of opposite sign muons and the other decays to b$\overline{\mathrm{b}}$. Such signatures are predicted in a number of extensions of the standard model (SM), including next-to-minimal supersymmetry and two-Higgs-doublet models with an additional scalar singlet. The results are based on a data set of proton-proton collisions corresponding to an integrated luminosity of 35.9 fb$^{-1}$, accumulated with the CMS experiment at the CERN LHC in 2016 at a centre-of-mass energy of 13 TeV. No statistically significant excess is observed with respect to the SM backgrounds in the search region for pseudoscalar masses from 20 GeV to half of the Higgs boson mass. Upper limits at 95% confidence level are set on the product of the production cross section and branching fraction, $\sigma_{\mathrm{h}}\mathcal{B}$(h $\to$ a$_1$ a$_1$ $\to$ $\mu^+\mu^-\mathrm{b}\bar{\mathrm{b}}$), ranging from 5 to 33 fb, depending on the pseudoscalar mass. Corresponding limits on the branching fraction, assuming the SM prediction for $\sigma_{\mathrm{h}}$, are (1$-$7)$\times$ 10$^{-4}$.
Observed and expected upper limits at 95% CL on the product of the Higgs boson production cross section and B(h->aa->mumubb)
Observed and expected upper limits at 95% CL on the branching fraction of (h->aa->mumubb)
A search is presented for pairs of light pseudoscalar bosons, in the mass range from 4 to 15 GeV, produced from decays of the 125 GeV Higgs boson. The decay modes considered are final states that arise when one of the pseudoscalars decays to a pair of tau leptons, and the other one either into a pair of tau leptons or muons. The search is based on proton-proton collisions collected by the CMS experiment in 2016 at a center-of-mass energy of 13 TeV that correspond to an integrated luminosity of 35.9 fb${-1}$. The 2$\mu$2$\tau$ and 4$\tau$ channels are used in combination to constrain the product of the Higgs boson production cross section and the branching fraction into 4$\tau$ final state, $\sigma\mathcal{B}$, exploiting the linear dependence of the fermionic coupling strength of pseudoscalar bosons on the fermion mass. No significant excess is observed beyond the expectation from the standard model. The observed and expected upper limits at 95% confidence level on $\sigma\mathcal{B}$, relative to the standard model Higgs boson production cross section, are set respectively between 0.022 and 0.23 and between 0.027 and 0.19 in the mass range probed by the analysis.
Expected and observed 95% CL upper limits on (sigma(pp->h)/sigma(pp->hSM)) * B(h -> aa -> tautautautau) as a function of m(a) obtained from the 13 TeV data, where h(SM) is the Higgs boson of the standard model, h is the observed particle with mass of 125 GeV, and (a) denotes a light Higgs-like state.
Measurements are presented of associated production of a W boson and a charm quark (W+c) in proton-proton collisions at a center-of-mass energy of 13 TeV. The data correspond to an integrated luminosity of 35.7 fb$^{-1}$ collected by the CMS experiment at the CERN LHC. The W bosons are identified by their decay into a muon and a neutrino. The charm quarks are tagged via the full reconstruction of D$^*$(2010)$^\pm$ mesons that decay via D$^*$(2010)$^\pm \to$ D$^0$ + $\pi^\pm \to$ K$^{\mp}$ + $\pi^\pm$ + $\pi^\pm$. A cross section is measured in the fiducial region defined by the muon transverse momentum $p_{T}^{\mu} >$ 26 GeV, muon pseudorapidity $|\eta^{\mu}| <$ 2.4, and charm quark transverse momentum $p_{T}^{c} >$ 5 GeV. The inclusive cross section for this kinematic range is $\sigma$(W+c) = 1026 $\pm$ 31 (stat) $\substack{+76\\-72}$ (syst) pb. The cross section is also measured differentially as a function of the pseudorapidity of the muon from the W boson decay. These measurements are compared with theoretical predictions and are used to probe the strange quark content of the proton.
The differential measurement of W + charm as a function of the absolute peudorapidity of the muon originating from the W boson.
The differential measurement of W+ + cbar as a function of the absolute peudorapidity of the muon originating from the W boson.
The differential measurement of W- + c as a function of the absolute peudorapidity of the muon originating from the W boson.
A search is presented for the production of a Higgs boson in association with a single top quark, based on data collected in 2016 by the CMS experiment at the LHC at a center-of-mass energy of 13 TeV, which corresponds to an integrated luminosity of 35.9 fb$^{-1}$. The production cross section for this process is highly sensitive to the absolute values of the top quark Yukawa coupling, $y_t$, the Higgs boson coupling to vector bosons, $g_\mathrm{HVV}$, and, uniquely, to their relative sign. Analyses using multilepton signatures, targeting H $\to$ WW, H $\to$ $\tau\tau$, and H $\to$ ZZ decay modes, and signatures with a single lepton and a $\mathrm{b\overline{b}}$ pair, targeting the H $\to$ $\mathrm{b\overline{b}}$ decay, are combined with a reinterpretation of a measurement in the H $\to$ $\gamma\gamma$ channel to constrain $y_\mathrm{t}$. For a standard model-like value of $g_\mathrm{HVV}$, the data favor positive values of $y_\mathrm{t}$ and exclude values of $y_\mathrm{t}$ below about $-$0.9 $y_\mathrm{t}^\mathrm{SM}$.
Expected and observed 95% CL upper limits on the tH production cross section times $H \to WW/ZZ/\tau\tau/b\bar{b}/\gamma\gamma$ branching fraction for a scenario of inverted couplings ($\kappa_t=-1.0$ and $\kappa_V=1.0$, top rows), vanishing top quark Yukawa coupling ($\kappa_t=0.0$ and $\kappa_V=1.0$, middle rows), and for an SM-like signal ($\kappa_t=1.0$ and $\kappa_V=1.0$, bottom rows), in pb. The Higgs to vector boson couplings is considered to be SM-like. The expected limit is calculated on a background-only data set, i.e., without tH contribution, but including a coupling dependent contribution from the ttH production. The ttH normalization is kept fixed in the fit, while the tH cross section is allowed to float. Limits can be compared to the expected product of tH cross sections and branching fractions of 0.83, 0.28, and 0.077 pb for the inverted top quark Yukawa coupling, the vanishing top-Yukawa and the SM-like scenario.
Observed and expected 95% CL upper limit on the tH cross section times combined $HH \to WW/ZZ/\tau\tau/b\bar{b}/\gamma\gamma$ branching fraction for different values of the top-Yukawa coupling modifier, assuming SM-like Higgs to vector boson couplings. The expected limit is calculated on a background-only data set, i.e., without tH contribution, but including a coupling dependent contribution from the ttH production. The ttH normalization is kept fixed in the fit, while the tH cross section is allowed to float.
A search is presented for massive narrow resonances decaying either into two Higgs bosons, or into a Higgs boson and a W or Z boson. The decay channels considered are HH$\to \mathrm{b\overline{b}}\tau^{+}\tau^{-}$ and VH$ \to \mathrm{q\overline{q}}\tau^{+}\tau^{-}$, where H denotes the Higgs boson, and V denotes the W or Z boson. This analysis is based on a data sample of proton-proton collisions collected at a center-of-mass energy of 13 TeV by the CMS Collaboration, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. For the TeV-scale mass resonances considered, substructure techniques provide ways to differentiate among the hadronization products from vector boson decays to quarks, Higgs boson decays to bottom quarks, and quark- or gluon-induced jets. Reconstruction techniques are used that have been specifically optimized to select events in which the tau lepton pair is highly boosted. The observed data are consistent with standard model expectations and upper limits are set at 95% confidence level on the product of cross section and branching fraction for resonance masses between 0.9 and 4.0 TeV. Exclusion limits are set in the context of bulk radion and graviton models: spin-0 radion resonances are excluded below a mass of 2.7 TeV at 95% confidence level. In the spin-1 heavy vector triplet framework, mass-degenerate W' and Z' resonances with dominant couplings to the standard model gauge bosons are excluded below a mass of 2.8 TeV at 95% confidence level. There are the first limits for these decay channels at $\sqrt{s}=$ 13 TeV.
Observed 95% CL upper limits on the product of the production cross section and the branching fraction for a new spin-0 resonance decaying to HH, as a function of the resonance mass hypothesis.
Observed 95% CL upper limits on the product of the production cross section and the branching fraction for a new spin-2 resonance decaying to HH, as a function of the resonance mass hypothesis.
Observed 95% CL upper limits on the product of the production cross section and the branching fraction for a new spin-1 W prime resonance decaying to WH, as a function of the resonance mass hypothesis.
Two related searches for phenomena beyond the standard model (BSM) are performed using events with hadronic jets and significant transverse momentum imbalance. The results are based on a sample of proton-proton collisions at a center-of-mass energy of 13 TeV, collected by the CMS experiment at the LHC in 2016-2018 and corresponding to an integrated luminosity of 137 fb$^{-1}$. The first search is inclusive, based on signal regions defined by the hadronic energy in the event, the jet multiplicity, the number of jets identified as originating from bottom quarks, and the value of the kinematic variable $M_\mathrm{T2}$ for events with at least two jets. For events with exactly one jet, the transverse momentum of the jet is used instead. The second search looks in addition for disappearing tracks produced by BSM long-lived charged particles that decay within the volume of the tracking detector. No excess event yield is observed above the predicted standard model background. This is used to constrain a range of BSM models that predict the following: the pair production of gluinos and squarks in the context of supersymmetry models conserving $R$-parity, with or without intermediate long-lived charginos produced in the decay chain; the resonant production of a colored scalar state decaying to a massive Dirac fermion and a quark; or the pair production of scalar and vector leptoquarks each decaying to a neutrino and a top, bottom, or light-flavor quark. In most of the cases, the results obtained are the most stringent constraints to date.
Definitions of super signal regions, along with predictions, observed data, and the observed 95% CL upper limits on the number of signal events contributing to each region ($N_{95}^\mathrm{max}$). The limits are given under assumptions of 0% and 15% for the uncertainty on the signal acceptance. All selection criteria as in the full analysis are applied. For regions with $N_\mathrm{j}=1$, $H_\mathrm{T}\equiv p_\mathrm{T}^\mathrm{jet}$.
Exclusion limits at 95% CL for direct gluino pair production, where the gluinos decay to light-flavor quarks ($\tilde{g}\to q\bar{q}\tilde{\chi}_1^0$). Signal cross sections are calculated at approximately NNLO+NNLL order in $\alpha_S$, assuming unity branching fraction to $q\bar{q}\tilde{\chi}_1^0$.
Exclusion limits at 95% CL for direct gluino pair production, where the gluinos decay to light-flavor quarks and either a $\tilde{\chi}_2^0$ that decays to $Z\tilde{\chi}_1^0$ (1/3 of the time), or a $\tilde{\chi}_1^\pm$ that decays to $W^\pm\tilde{\chi}_1^0$ (2/3 of the time). Signal cross sections are calculated at approximately NNLO+NNLL order in $\alpha_S$, assuming unity branching fraction to $q_i\bar{q}_j V\tilde{\chi}_1^0$.
A data sample of events from proton-proton collisions with at least two jets, and two isolated same-sign or three or more charged leptons, is studied in a search for signatures of new physics phenomena. The data correspond to an integrated luminosity of 137 fb$^{-1}$ at a center-of-mass energy of 13 TeV, collected in 2016-2018 by the CMS experiment at the LHC. The search is performed using a total of 168 signal regions defined using several kinematic variables. The properties of the events are found to be consistent with the expectations from standard model processes. Exclusion limits at 95% confidence level are set on cross sections for the pair production of gluinos or squarks for various decay scenarios in the context of supersymmetric models conserving or violating R parity. The observed lower mass limits are as large as 2.1 TeV for gluinos and 0.9 TeV for top and bottom squarks. To facilitate reinterpretations, model-independent limits are provided in a set of simplified signal regions.
Exclusion regions at 95% CL in the $m_{\tilde{\chi}_1^0}$ versus $m_{\tilde{g}}$ plane for the T1tttt (upper left) and T5ttbbWW (upper right) models, with off-shell third-generation squarks, and the T5tttt (lower left) and T5ttcc (lower right) models, with on-shell third-generation squarks. For the T5ttbbWW model, $m_{\tilde{\chi}_1^\pm} = m_{\tilde{\chi}_1^0} + 5 GeV$, for the T5tttt model, $m_{\tilde{t}} - m_{\tilde{\chi}_1^0} = m_t$, and for the T5ttcc model, $m_{\tilde{t}} - m_{\tilde{\chi}_1^0} = 20 GeV$ and the decay proceeds through $\tilde{t} \to c \tilde{\chi}_1^0$. The right-hand side color scale indicates the excluded cross section values for a given point in the SUSY particle mass plane. The solid black curves represent the observed exclusion limits assuming the approximate-NNLO+NNLL cross sections (thick line), or their variations of $\pm 1$ standard deviations (s.d.) (thin lines). The dashed red curves show the expected limits with the corresponding $\pm 1$ s.d. and $\pm 2$ s.d. uncertainties. Excluded regions are to the left and below the limit curves.
Exclusion regions at 95% CL in the $m_{\tilde{\chi}_1^0}$ versus $m_{\tilde{g}}$ plane for the T1tttt (upper left) and T5ttbbWW (upper right) models, with off-shell third-generation squarks, and the T5tttt (lower left) and T5ttcc (lower right) models, with on-shell third-generation squarks. For the T5ttbbWW model, $m_{\tilde{\chi}_1^\pm} = m_{\tilde{\chi}_1^0} + 5 GeV$, for the T5tttt model, $m_{\tilde{t}} - m_{\tilde{\chi}_1^0} = m_t$, and for the T5ttcc model, $m_{\tilde{t}} - m_{\tilde{\chi}_1^0} = 20 GeV$ and the decay proceeds through $\tilde{t} \to c \tilde{\chi}_1^0$. The right-hand side color scale indicates the excluded cross section values for a given point in the SUSY particle mass plane. The solid black curves represent the observed exclusion limits assuming the approximate-NNLO+NNLL cross sections (thick line), or their variations of $\pm 1$ standard deviations (s.d.) (thin lines). The dashed red curves show the expected limits with the corresponding $\pm 1$ s.d. and $\pm 2$ s.d. uncertainties. Excluded regions are to the left and below the limit curves.
Exclusion regions at 95% CL in the $m_{\tilde{\chi}_1^0}$ versus $m_{\tilde{g}}$ plane for the T1tttt (upper left) and T5ttbbWW (upper right) models, with off-shell third-generation squarks, and the T5tttt (lower left) and T5ttcc (lower right) models, with on-shell third-generation squarks. For the T5ttbbWW model, $m_{\tilde{\chi}_1^\pm} = m_{\tilde{\chi}_1^0} + 5 GeV$, for the T5tttt model, $m_{\tilde{t}} - m_{\tilde{\chi}_1^0} = m_t$, and for the T5ttcc model, $m_{\tilde{t}} - m_{\tilde{\chi}_1^0} = 20 GeV$ and the decay proceeds through $\tilde{t} \to c \tilde{\chi}_1^0$. The right-hand side color scale indicates the excluded cross section values for a given point in the SUSY particle mass plane. The solid black curves represent the observed exclusion limits assuming the approximate-NNLO+NNLL cross sections (thick line), or their variations of $\pm 1$ standard deviations (s.d.) (thin lines). The dashed red curves show the expected limits with the corresponding $\pm 1$ s.d. and $\pm 2$ s.d. uncertainties. Excluded regions are to the left and below the limit curves.
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 $^{+0.62}_{-0.34}$. Limits are placed on three anomalous quartic gauge couplings and on the production of massive axionlike particles.
Lost-lepton and three-lepton background contributions.
Non-prompt lepton background estimates.
Summary of typical systematic uncertainties of estimated background contributions.
A measurement is reported of the jet mass distribution in hadronic decays of boosted top quarks produced in pp collisions at $\sqrt{s} =$ 13 TeV. The data were collected with the CMS detector at the LHC and correspond to an integrated luminosity of 35.9 fb$^{-1}$. The measurement is performed in the lepton+jets channel of $\mathrm{t\bar{t}}$ events, where the lepton is an electron or muon. The products of the hadronic top quark decay t $\to$ bW $\to$ bq$\mathrm{\bar{q}}'$ are reconstructed as a single jet with transverse momentum larger than 400 GeV. The $\mathrm{t\bar{t}}$ cross section as a function of the jet mass is unfolded at the particle level and used to extract a value of the top quark mass of 172.6 $\pm$ 2.5 GeV. A novel jet reconstruction technique is used for the first time at the LHC, which improves the precision by a factor of three relative to an earlier measurement. This highlights the potential of measurements using boosted top quarks, where the new technique will enable future precision measurements.
Reconstructed distribution of $m_\mathrm{jet}$ after the full event selection in the lepton+jets channel.
The particle-level $\mathrm{t}\overline{\mathrm{t}}$ differential cross section in the fiducial region as a function of the XCone-jet mass.
The particle-level $\mathrm{t}\overline{\mathrm{t}}$ differential cross section in the fiducial region as a function of the XCone-jet mass.
Measurement of the fiducial inclusive and differential production cross sections of the Higgs boson in proton-proton collisions at $\sqrt{s} =$ 13 TeV are performed using events where the Higgs boson decays into a pair of W bosons that subsequently decay into a final state with an electron, a muon, and a pair of neutrinos. The analysis is based on data collected with the CMS detector at the LHC during 2016-2018, corresponding to an integrated luminosity of 137 fb$^{-1}$. Production cross sections are measured as a function of the transverse momentum of the Higgs boson and the associated jet multiplicity. The Higgs boson signal is extracted and simultaneously unfolded to correct for selection efficiency and resolution effects using maximum-likelihood fits to the observed distributions in data. The integrated fiducial cross section is measured to be 86.5 $\pm$ 9.5 fb, consistent with the Standard Model expectation of 82.5 $\pm$ 4.2 fb. No significant deviation from the Standard Model expectations is observed in the differential measurements.
The fiducial differential signal strength and cross section in each Higgs pT bin. Both the unregularized and regularized signal strengthes are given. For the regularized case the uncertainty breakdown is given in terms of statistical (stat), experimental (exp), theoretical uncertainties on the background (bkg) and on the signal (sig), and the luminosity uncertainty (lumi). The regularization estimated bias (bias) is also given. The fiducial cross section and its full uncertainty in each bin are also given. The last bin is inclusive.
The correlation matrix for the ptH measurements, both for the unregularized and regularized fits. The last bin is inclusive.
The fiducial differential signal strength and cross section in each njet bin. The uncertainty breakdown is given in terms of statistical (stat), experimental (exp), theoretical uncertainties on the background (bkg) and on the signal (sig), and the luminosity uncertainty (lumi). The fiducial cross section and its full uncertainty in each bin are also given. The last bin is inclusive.
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