Measurement of the $t\bar{t}$ production cross section using events in the e$\mu$ final state in pp collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
No Journal Information, 2016.
Inspire Record 1497736 DOI 10.17182/hepdata.76735

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 792 +/- 8 (stat) +/- 37 (syst) +/- 21 (lumi) pb, in agreement with the expectation from the standard model.

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Measurement of the top quark mass using charged particles in pp collisions at $\sqrt s =$ 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev. D93 (2016) 092006, 2016.
Inspire Record 1430902 DOI 10.17182/hepdata.72898
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Measurement of spin correlations in $t\bar{t}$ production using the matrix element method in the muon+jets final state in pp collisions at $\sqrt{s} =$ 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B758 (2016) 321-346, 2016.
Inspire Record 1405439 DOI 10.17182/hepdata.70230
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Measurement of the t-tbar production cross section in the e-mu channel in proton-proton collisions at sqrt(s) = 7 and 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
JHEP 1608 (2016) 029, 2016.
Inspire Record 1426692 DOI 10.17182/hepdata.74208

The inclusive cross section for top quark pair production is measured in proton-proton collisions at $ \sqrt{s}=7 $ and 8 TeV, corresponding to 5.0 and 19.7 fb$^{−1}$, respectively, with the CMS experiment at the LHC. The cross sections are measured in the electron-muon channel using a binned likelihood fit to multi-differential final state distributions related to identified b quark jets and other jets in the event. The measured cross section values are 173.6 ± 2.1(stat)$_{− 4.0}^{+ 4.5}$ (syst) ± 3.8(lumi)pb at $ \sqrt{s}=7 $ TeV, and 244.9 ± 1.4(stat)$_{− 5.5}^{+ 6.3}$ (syst) ± 6.4(lumi)pb at $ \sqrt{s}=8 $ TeV, in good agreement with QCD calculations at next-to-next-to-leading-order accuracy. The ratio of the cross sections measured at 7 and 8 TeV is determined, as well as cross sections in the fiducial regions defined by the acceptance requirements on the two charged leptons in the final state. The cross section results are used to determine the top quark pole mass via the dependence of the theoretically predicted cross section on the mass, giving a best result of 173. 8$_{− 1.8}^{+ 1.7}$ GeV. The data at $ \sqrt{s}=8 $ TeV are also used to set limits, for two neutralino mass values, on the pair production of supersymmetric partners of the top quark with masses close to the top quark mass.

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Inclusive and differential measurements of the $t\overline{t}$ charge asymmetry in pp collisions at $\sqrt{s} =$ 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B757 (2016) 154-179, 2016.
Inspire Record 1382590 DOI 10.17182/hepdata.68759
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Measurement of the top quark pair production cross section in proton-proton collisions at $\sqrt(s) =$ 13 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev.Lett. 116 (2016) 052002, 2016.
Inspire Record 1398582 DOI 10.17182/hepdata.69538
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Measurement of the ratio $\mathcal B(t \to Wb)/\mathcal B(t \to Wq)$ in pp collisions at $\sqrt{s}$ = 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Lett. B736 (2014) 33-57, 2014.
Inspire Record 1289223 DOI 10.17182/hepdata.64489

The ratio of the top-quark branching fractions $R = B(t \to Wb)/B(t \to Wq)$, where the denominator includes the sum over all down-type quarks (q = b, s, d), is measured in the $t\bar{t}$ dilepton final state with proton-proton collision data at $\sqrt{s}$ = 8 TeV from an integrated luminosity of 19.7 inverse-femtobarns, collected with the CMS detector. In order to quantify the purity of the signal sample, the cross section is measured by fitting the observed jet multiplicity, thereby constraining the signal and background contributions. By counting the number of b jets per event, an unconstrained value of R = 1.014 $\pm$ 0.003 (stat) $\pm$ 0.032 (syst) is measured, in good agreement with the standard model prediction. A lower limit R greater than 0.955 at the 95% confidence level is obtained after requiring R lower than one, and a lower limit on the Cabibbo-Kobayashi-Maskawa matrix element |$V_tb$| greater than 0.975 is set at 95% confidence level. The result is combined with a previous CMS measurement of the t-channel single-top-quark cross section to determine the top-quark total decay width, $\Gamma_t$ = 1.36 $\pm$ 0.02 (stat)$^{+0.14}_{-0.11}$ (syst) GeV.

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Measurement of the $t \bar{t}$ production cross section in the dilepton channel in pp collisions at $\sqrt{s}$ = 8 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 1402 (2014) 024, 2014.
Inspire Record 1275617 DOI 10.17182/hepdata.64868

The top-antitop quark (t t-bar) production cross section is measured in proton-proton collisions at sqrt(s) = 8 TeV with the CMS experiment at the LHC, using a data sample corresponding to an integrated luminosity of 5.3 inverse femtobarns. The measurement is performed by analysing events with a pair of electrons or muons, or one electron and one muon, and at least two jets, one of which is identified as originating from hadronisation of a bottom quark. The measured cross section is 239 +/- 2 (stat.) +/- 11 (syst.) +/- 6 (lum.) pb, for an assumed top-quark mass of 172.5 GeV, in agreement with the prediction of the standard model.

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Measurement of the $t\bar{t}$ production cross section in $pp$ collisions at $\sqrt{s}=7$ TeV with lepton + jets final states

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Lett. B720 (2013) 83-104, 2013.
Inspire Record 1208913 DOI 10.17182/hepdata.66907

A measurement of the t t-bar production cross section in pp collisions at sqrt(s) = 7 TeV is presented. The results are based on data corresponding to an integrated luminosity of 2.3 inverse femtobarns collected by the CMS detector at the LHC. Selected events are required to have one isolated, high transverse momentum electron or muon, large missing transverse energy, and hadronic jets, at least one of which must be consistent with having originated from a b quark. The measured cross section is 158.1 +/- 2.1 (stat.) +/- 10.2 (syst.) +/- 3.5 (lum.) pb, in agreement with standard model predictions.

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Measurement of jet multiplicity distributions in $\mathrm {t}\overline{\mathrm {t}}$ production in pp collisions at $\sqrt{s} = 7\,\text {TeV} $

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Eur.Phys.J. C74 (2015) 3014, 2015.
Inspire Record 1290126 DOI 10.17182/hepdata.64426
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Search for baryon number violation in top-quark decays

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Lett. B731 (2014) 173-196, 2014.
Inspire Record 1257387 DOI 10.17182/hepdata.62206

A search for baryon number violation (BNV) in top-quark decays is performed using pp collisions produced by the LHC at sqrt(s) = 8 TeV. The top-quark decay considered in this search results in one light lepton (muon or electron), two jets, but no neutrino in the final state. Data used for the analysis were collected by the CMS detector and correspond to an integrated luminosity of 19.5 inverse femtobarns. The event selection is optimized for top quarks produced in pairs, with one undergoing the BNV decay and the other the standard model hadronic decay to three jets. No significant excess of events over the expected yield from standard model processes is observed. The upper limits at 95% confidence level on the branching fraction of the BNV top-quark decay are calculated to be 0.0016 and 0.0017 for the muon and the electron channels, respectively. Assuming lepton universality, an upper limit of 0.0015 results from the combination of the two channels. These limits are the first that have been obtained on a BNV process involving the top quark.

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Searches for new physics using the $t\bar{t}$ invariant mass distribution in pp collisions at $\sqrt{s}$=8  TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
Phys.Rev.Lett. 111 (2013) 211804, 2013.
Inspire Record 1253367 DOI 10.17182/hepdata.62178

Searches for anomalous top quark-antiquark production are presented, based on pp collisions at sqrt(s) = 8 TeV. The data, corresponding to an integrated luminosity of 19.7 inverse femtobarns, were collected with the CMS detector at the LHC. The observed ttbar 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.

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Measurements of the $t\bar{t}$ charge asymmetry using the dilepton decay channel in pp collisions at $\sqrt{s} =$ 7 TeV

The CMS collaboration Chatrchyan, Serguei ; Khachatryan, Vardan ; Sirunyan, Albert M ; et al.
JHEP 1404 (2014) 191, 2014.
Inspire Record 1281538 DOI 10.17182/hepdata.64729
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Measurement of the charge asymmetry in top quark pair production in pp collisions at $\sqrt(s) =$ 8 TeV using a template method

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev. D93 (2016) 034014, 2016.
Inspire Record 1388178 DOI 10.17182/hepdata.69208
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Measurement of the top quark mass using proton-proton data at ${\sqrt{(s)}}$ = 7 and 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev. D93 (2016) 072004, 2016.
Inspire Record 1393269 DOI 10.17182/hepdata.71988
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First Measurement of the Cross Section for Top-Quark Pair Production in Proton-Proton Collisions at $\sqrt{s}=7$ TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M. ; Tumasyan, Armen ; et al.
Phys.Lett. B695 (2011) 424-443, 2011.
Inspire Record 874738 DOI 10.17182/hepdata.63811

The first measurement of the cross section for top-quark pair production in pp collisions at the LHC at center-of-mass energy sqrt(s)= 7 TeV has been performed using 3.1 {\pm} 0.3 inverse pb of data recorded by the CMS detector. This result utilizes the final state with two isolated, highly energetic charged leptons, large missing transverse energy, and two or more jets. Backgrounds from Drell-Yan and non-W/Z boson production are estimated from data. Eleven events are observed in the data with 2.1 {\pm} 1.0 events expected from background. The measured cross section is 194 {\pm} 72 (stat.) {\pm} 24 (syst.) {\pm} 21 (lumi.) pb, consistent with next-to-leading order predictions.

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Measurement of the W boson helicity fractions in the decays of top quark pairs to lepton+jets final states produced in pp collisions at sqrt(s) = 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
No Journal Information, 2016.
Inspire Record 1466294 DOI 10.17182/hepdata.74337
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Measurement of the mass of the top quark in decays with a J/$\psi$ meson in pp collisions at 8 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
No Journal Information, 2016.
Inspire Record 1480862 DOI 10.17182/hepdata.75539

A first measurement is presented of the top quark mass using the decay channel $ \mathrm{ t } \to ( \mathrm{ W } \to\ell\nu )$, $( \mathrm{ b } \to \mathrm{ J } / \psi + \mathrm{X} \to \mu \mu + \mathrm{X} ) $, in events selected in proton-proton collisions and recorded with the CMS detector at the LHC at a center-of-mass energy of 8 TeV. The data correspond to an integrated luminosity of 19.7 fb$^{-1}$, with 666 $\mathrm{ t \bar{t} }$ and single top quark candidate events containing a reconstructed $\mathrm{ J } / \psi$ candidate decaying into an oppositely-charged muon pair. The mass of the ($\mathrm{ J } / \psi+\ell$) system, where $\ell$ is an electron or a muon from W boson decay, is used to extract a top quark mass of 173.5 $\pm$ 3.0 (stat) $\pm$ 0.9 (syst) GeV.

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Measurement of double-differential cross sections for top quark pair production in pp collisions at sqrt(s) = 8 TeV and impact on parton distribution functions

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
No Journal Information, 2017.
Inspire Record 1516191 DOI 10.17182/hepdata.77008

Normalized double-differential cross sections for top quark pair (ttbar) production are measured in pp collisions at a centre-of-mass energy of 8 TeV with the CMS experiment at the LHC. The analyzed data correspond to an integrated luminosity of 19.7 inverse femtobarns. The measurement is performed in the dilepton e+/- mu-/+ final state. The ttbar cross section is determined as a function of various pairs of observables characterizing the kinematics of the top quark and ttbar system. The data are compared to calculations using perturbative quantum chromodynamics at next-to-leading and approximate next-to-next-to-leading orders. They are also compared to predictions of Monte Carlo event generators that complement fixed-order computations with parton showers, hadronization, and multiple-parton interactions. Overall agreement is observed with the predictions, which is improved when the latest global sets of proton parton distribution functions are used. The inclusion of the measured ttbar cross sections in a fit of parametrized parton distribution functions is shown to have significant impact on the gluon distribution.

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Measurements of top quark pair relative differential cross-sections with ATLAS in $pp$ collisions at $\sqrt{s}=7$ TeV

The ATLAS collaboration Aad, Georges ; Abajyan, Tatevik ; Abbott, Brad ; et al.
Eur.Phys.J. C73 (2013) 2261, 2013.
Inspire Record 1123657 DOI 10.17182/hepdata.62290

Measurements are presented of differential cross-sections for top quark pair production in pp collisions at relative to the total inclusive top quark pair production cross-section. A data sample of 2.05 fb(−1) recorded by the ATLAS detector at the Large Hadron Collider is used. Relative differential cross-sections are derived as a function of the invariant mass, the transverse momentum and the rapidity of the top quark pair system. Events are selected in the lepton (electron or muon) + jets channel. The background-subtracted differential distributions are corrected for detector effects, normalized to the total inclusive top quark pair production cross-section and compared to theoretical predictions. The measurement uncertainties range typically between 10 % and 20 % and are generally dominated by systematic effects. No significant deviations from the Standard Model expectations are observed.

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