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 $\chi_\mathrm{b1}$(3P) and $\chi_\mathrm{b2}$(3P) states are observed through their $\Upsilon$(3S) $\gamma$ decays, using an event sample of proton-proton collisions collected by the CMS experiment at the CERN LHC. The data were collected at a center-of-mass energy of 13 TeV and correspond to an integrated luminosity of 80.0 fb$^{-1}$. The $\Upsilon$(3S) mesons are identified through their dimuon decay channel, while the low-energy photons are detected after converting to e$^+$e$^-$ pairs in the silicon tracker, leading to a $\chi_\mathrm{b}$(3P) mass resolution of 2.2 MeV. This is the first time that the $J =$ 1 and 2 states are well resolved and their masses individually measured: 10$\,$513.42 $\pm$ 0.41 (stat) $\pm$ 0.18 (syst) MeV and 10$\,$524.02 $\pm$ 0.57 (stat) $\pm$ 0.18 (syst) MeV; they are determined with respect to the world-average value of the $\Upsilon$(3S) mass, which has an uncertainty of 0.5 MeV. The mass splitting is measured to be 10.60 $\pm$ 0.64 (stat) $\pm$ 0.17 (syst) MeV.
Observation of the $\chi_{b1}(3P)$ and $\chi_{b2}(3P)$ and measurement of their masses.
Observation of the $\chi_{b1}(3P)$ and $\chi_{b2}(3P)$ and mass splitting measurement.
A search for an exotic decay of the Higgs boson to a pair of light pseudoscalar bosons is performed for the first time in the final state with two b quarks and two $\tau$ leptons. The search is motivated in the context of models of physics beyond the standard model (SM), such as two Higgs doublet models extended with a complex scalar singlet (2HDM+S), which include the next-to-minimal supersymmetric SM (NMSSM). The results are based on a data set of proton-proton collisions corresponding to an integrated luminosity of 35.9 fb$^{-1}$, accumulated by the CMS experiment at the LHC in 2016 at a center-of-mass energy of 13 TeV. Masses of the pseudoscalar boson between 15 and 60 GeV are probed, and no excess of events above the SM expectation is observed. Upper limits between 3 and 12% are set on the branching fraction $\mathcal{B}$(h $\to$ aa $\to$ 2$\tau$2b) assuming the SM production of the Higgs boson. Upper limits are also set on the branching fraction of the Higgs boson to two light pseudoscalar bosons in different 2HDM+S scenarios. Assuming the SM production cross section for the Higgs boson, the upper limit on this quantity is as low as 20% for a mass of the pseudoscalar of 40 GeV in the NMSSM.
Expected and observed 95% CL upper limits on (sigma(pp->h)/sigma(pp->hSM)) * B(h -> aa -> bbtautau) as a function of m(a), 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, as obtained from the 13 TeV data.
A measurement is presented of the associated production of a single top quark and a W boson in proton-proton collisions at $\sqrt{s}=$ 13 TeV by the CMS Collaboration at the CERN LHC. The data collected corresponds to an integrated luminosity of 35.9 fb$^{-1}$. The measurement is performed using events with one electron and one muon in the final state along with at least one jet originated from a bottom quark. A multivariate discriminant, exploiting the kinematic properties of the events, is used to separate the signal from the dominant $\mathrm{t\overline{t}}$ background. The measured cross section of 63.1 $\pm$ 1.8 (stat) $\pm$ 6.4 (syst) $\pm$ 2.1 (lumi) pb is in agreement with the standard model expectation.
The measured total cross sections based on the $\rm{e}^\pm \mu^\mp$ decay channel. The first uncertainty is the statistical, the second is the systematic, and the last due to the integrated luminosity.
Summary of the individual contributions to the uncertainty in the $\sigma_{tW}$ measurement.
A search for exotic Higgs boson decays to light pseudoscalars in the final state of two muons and two $\tau$ leptons is performed using proton-proton collision data recorded by the CMS experiment at the LHC at a center-of-mass energy of 13 TeV in 2016, corresponding to an integrated luminosity of 35.9 fb$^{-1}$. Masses of the pseudoscalar boson between 15.0 and 62.5 GeV are probed, and no significant excess of data is observed above the prediction of the standard model. Upper limits are set on the branching fraction of the Higgs boson to two light pseudoscalar bosons in different types of two-Higgs-doublet models extended with a complex scalar singlet.
Expected and observed 95% CL upper limits on (sigma(pp->h)/sigma(pp->hSM)) * B(h -> aa -> mumutautau) as a function of m(a), 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, as obtained from the 13 TeV data.
The mass of the top quark is measured using a sample of $\mathrm{t\overline{t}}$ events collected by the CMS detector using proton-proton collisions at $\sqrt{s} =$ 13 TeV at the CERN LHC. Events are selected with one isolated muon or electron and at least four jets from data corresponding to an integrated luminosity of 35.9 fb$^{-1}$. For each event the mass is reconstructed from a kinematic fit of the decay products to a $\mathrm{t\overline{t}}$ hypothesis. Using the ideogram method, the top quark mass is determined simultaneously with an overall jet energy scale factor (JSF), constrained by the mass of the W boson in $\mathrm{q\overline{q}'}$ decays. The measurement is calibrated on samples simulated at next-to-leading order matched to a leading-order parton shower. The top quark mass is found to be 172.25 $\pm$ 0.08 (stat+JSF) $\pm$ 0.62 (syst) GeV. The dependence of this result on the kinematic properties of the event is studied and compared to predictions of different models of $\mathrm{t\overline{t}}$ production, and no indications of a bias in the measurements are observed.
Measured top quark mass $m_{t}$
A search is presented for long-lived charged particles that decay within the CMS detector and produce the signature of a disappearing track. A disappearing track is an isolated track with missing hits in the outer layers of the silicon tracker, little or no energy in associated calorimeter deposits, and no associated hits in the muon detectors. This search uses data collected with the CMS detector in 2015 and 2016 from proton-proton collisions at a center-of-mass energy of 13 TeV at the LHC, corresponding to an integrated luminosity of 38.4 fb$^{-1}$. The results of the search are interpreted in the context of the anomaly-mediated supersymmetry breaking model. The data are consistent with the background-only hypothesis. Limits are set on the product of the cross section for direct production of charginos and their branching fraction to a neutralino and a pion, as a function of the chargino mass and lifetime. At 95% confidence level, charginos with masses below 715 (695) GeV are excluded for a lifetime of 3 (7) ns, as are charginos with lifetimes from 0.5 to 60 ns for a mass of 505 GeV. These are the most stringent limits using a disappearing track signature on this signal model for chargino lifetimes above $\approx$ 0.7 ns.
The expected and observed 95% CL upper limits on the product of the cross section for direct production of charginos and their branching fraction to $\widetilde{\chi}^{0}_{1}\mathrm{\pi^{\pm}}$ as a function of chargino mass for a chargino lifetime of 0.3 ns. The ratio of the vacuum expectation values of the two Higgs doublets, $\tan \beta$, is fixed to 5 with $\mu > 0$, where $\mu$ is the higgsino mass parameter. The direct chargino production cross section includes both $\widetilde{\chi}^{0}_{1}\widetilde{\chi}^\pm_{1}$ and $\widetilde{\chi}^\pm_{1}\widetilde{\chi}^\mp_{1}$ production in roughly a 2:1 ratio for all chargino masses considered, and the branching fraction of $\widetilde{\chi}^\pm_{1} \rightarrow \widetilde{\chi}^{0}_{1}\mathrm{\pi^{\pm}}$ is set to 100%. The theoretical prediction for the AMSB model is also shown.
The expected and observed 95% CL upper limits on the product of the cross section for direct production of charginos and their branching fraction to $\widetilde{\chi}^{0}_{1}\mathrm{\pi^{\pm}}$ as a function of chargino mass for a chargino lifetime of 3.3 ns. The ratio of the vacuum expectation values of the two Higgs doublets, $\tan \beta$, is fixed to 5 with $\mu > 0$, where $\mu$ is the higgsino mass parameter. The direct chargino production cross section includes both $\widetilde{\chi}^{0}_{1}\widetilde{\chi}^\pm_{1}$ and $\widetilde{\chi}^\pm_{1}\widetilde{\chi}^\mp_{1}$ production in roughly a 2:1 ratio for all chargino masses considered, and the branching fraction of $\widetilde{\chi}^\pm_{1} \rightarrow \widetilde{\chi}^{0}_{1}\mathrm{\pi^{\pm}}$ is set to 100%. The theoretical prediction for the AMSB model is also shown.
The expected and observed 95% CL upper limits on the product of the cross section for direct production of charginos and their branching fraction to $\widetilde{\chi}^{0}_{1}\mathrm{\pi^{\pm}}$ as a function of chargino mass for a chargino lifetime of 33 ns. The ratio of the vacuum expectation values of the two Higgs doublets, $\tan \beta$, is fixed to 5 with $\mu > 0$, where $\mu$ is the higgsino mass parameter. The direct chargino production cross section includes both $\widetilde{\chi}^{0}_{1}\widetilde{\chi}^\pm_{1}$ and $\widetilde{\chi}^\pm_{1}\widetilde{\chi}^\mp_{1}$ production in roughly a 2:1 ratio for all chargino masses considered, and the branching fraction of $\widetilde{\chi}^\pm_{1} \rightarrow \widetilde{\chi}^{0}_{1}\mathrm{\pi^{\pm}}$ is set to 100%. The theoretical prediction for the AMSB model is also shown.
The production of a Z boson, decaying to two charged leptons, in association with jets in proton-proton collisions at a centre-of-mass energy of 13 TeV is measured. Data recorded with the CMS detector at the LHC are used that correspond to an integrated luminosity of 2.19 fb$^{-1}$. The cross section is measured as a function of the jet multiplicity and its dependence on the transverse momentum of the Z boson, the jet kinematic variables (transverse momentum and rapidity), the scalar sum of the jet momenta, which quantifies the hadronic activity, and the balance in transverse momentum between the reconstructed jet recoil and the Z boson. The measurements are compared with predictions from four different calculations. The first two merge matrix elements with different parton multiplicities in the final state and parton showering, one of which includes one-loop corrections. The third is a fixed-order calculation with next-to-next-to-leading order accuracy for the process with a Z boson and one parton in the final state. The fourth combines the fully differential next-to-next-to-leading order calculation with next-to-next-to-leading logarithm resummation and parton showering.
Measured cross section for Z+jets as a function of the exclusive jet multiplicity, $N_{\text{jets}}$, and breakdown of the relative uncertainty.
Bin-to-bin correlation in the measured cross section for Z+jets as a function of the exclusive jet multiplicity, $N_{\text{jets}}$.
Measured cross section for Z+jets as a function of inclusive jet multiplicity, $N_{\text{jets}}^{\text{min}}$, and breakdown of the relative uncertainty.
The observation of Higgs boson production in association with a top quark-antiquark pair is reported, based on a combined analysis of proton-proton collision data at center-of-mass energies of $\sqrt{s}=$ 7, 8, and 13 TeV, corresponding to integrated luminosities of up to 5.1, 19.7, and 35.9 fb$^{-1}$, respectively. The data were collected with the CMS detector at the CERN LHC. The results of statistically independent searches for Higgs bosons produced in conjunction with a top quark-antiquark pair and decaying to pairs of W bosons, Z bosons, photons, $\tau$ leptons, or bottom quark jets are combined to maximize sensitivity. An excess of events is observed, with a significance of 5.2 standard deviations, over the expectation from the background-only hypothesis. The corresponding expected significance from the standard model for a Higgs boson mass of 125.09 GeV is 4.2 standard deviations. The combined best fit signal strength normalized to the standard model prediction is 1.26 ${^{+0.31}_{-0.26}}$.
Best fit value of the ttH signal strength modifier $\mu_{\mathrm{ttH}}$, with its 1 and 2 standard deviation confidence intervals ($\sigma$), for the five individual decay channels considered, the combined result for 7+8 TeV alone and for 13 TeV alone, and the overall combined result. The Higgs boson mass is taken to be 125.09 GeV. For the $\mathrm{H}\rightarrow\mathrm{ZZ}$ decay mode, $\mu_{\mathrm{ttH}}$ is constrained to be positive to prevent the corresponding event yield from becoming negative. The SM expectation is shown as a dashed vertical line.
Best fit value, with its uncertainty, of the ttH signal strength modifier $\mu_{\mathrm{ttH}}$, for the five individual decay channels considered, the combined result for 7+8 TeV alone and for 13 TeV alone, and the overall combined result. The total uncertainties are decomposed into their statistical (Stat), experimental systematic (Expt), background theory systematic (Thbgd), and signal theory systematic (Thsig) components.
Distribution of events as a function of the decimal logarithm of S/B, where S and B are the expected post-fit signal (with $\mu_{\mathrm{ttH}}$ = 1) and background yields, respectively, in each bin of the distributions considered in this combination. The shaded histogram shows the expected background distribution. The two hatched histograms, each stacked on top of the background histogram, show the signal expectation for the SM ($\mu_{\mathrm{ttH}}$ = 1) and the observed ($\mu_{\mathrm{ttH}}$ = 1.26) signal strengths.
A search for a new scalar resonance decaying to a pair of Z bosons is performed in the mass range from 130 GeV to 3 TeV, and for various width scenarios. The analysis is based on proton-proton collisions recorded by the CMS experiment at the LHC in 2016, corresponding to an integrated luminosity of 35.9 fb$^{-1}$ at a center-of-mass energy of 13 TeV. The Z boson pair decays are reconstructed using the 4$\ell$, 2$\ell$2q, and 2$\ell$2$\nu$ final states, where $\ell =$ e or $\mu$. Both gluon fusion and electroweak production of the scalar resonance are considered, with a free parameter describing their relative cross sections. A dedicated categorization of events, based on the kinematic properties of associated jets, and matrix element techniques are employed for an optimal signal and background separation. A description of the interference between signal and background amplitudes for a resonance of an arbitrary width is included. No significant excess of events with respect to the standard model expectation is observed and limits are set on the product of the cross section for a new scalar boson and the branching fraction for its decay to ZZ for a large range of masses and widths.
Expected and observed upper limits at the 95% CL on the pp --> X --> ZZ cross section as a function of $m_X$ with $\Gamma_X$=0 GeV with VBF fraction profiled.
Expected and observed upper limits at the 95% CL on the pp --> X --> ZZ cross section as a function of $m_X$ with $\Gamma_X$=0 GeV in VBF production mode.
Expected and observed upper limits at the 95% CL on the pp --> X --> ZZ cross section as a function of $m_X$ with $\Gamma_X$=10 GeV with VBF fraction profiled.
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