Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 2006 (2020) 146, 2020.
Inspire Record 1772050 DOI 10.17182/hepdata.95469

AbstractThe parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric $ \left({\hat{d}}_{\mathrm{t}}\right) $ and chromomagnetic $ \left({\hat{\mu}}_{\mathrm{t}}\right) $ moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb$^{−1}$. The linearized variable $ {A}_{\mathrm{FB}}^{(1)} $ is used to approximate the asymmetry. Candidate $ \mathrm{t}\overline{\mathrm{t}} $ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for $ \mathrm{t}\overline{\mathrm{t}} $ final states. The values found for the parameters are $ {A}_{\mathrm{FB}}^{(1)}={0.048}_{-0.087}^{+0.095}{\left(\mathrm{stat}\right)}_{-0.029}^{+0.020}\left(\mathrm{syst}\right),{\hat{\mu}}_{\mathrm{t}}=-{0.024}_{-0.009}^{+0.013}{\left(\mathrm{stat}\right)}_{-0.011}^{+0.016}\left(\mathrm{syst}\right), $ and a limit is placed on the magnitude of $ \left|{\hat{d}}_{\mathrm{t}}\right| $< 0.03 at 95% confidence level.[graphic not available: see fulltext]

3 data tables

Linearized top quark forward-backward production asymmetry $A_{FB}^{(1)}$

Top quark anomalous chromomagnetic dipole moment $\hat{\mu}_{t}$

Top quark anomalous chromoelectric dipole moment $\hat{d}_{t}$


Measurement of the top quark pair production cross section in dilepton final states containing one $\tau$ lepton in pp collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 2002 (2020) 191, 2020.
Inspire Record 1767671 DOI 10.17182/hepdata.93743

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.

3 data tables

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.


Measurement of the top quark polarization and $\mathrm{t\bar{t}}$ spin correlations using dilepton final states in proton-proton collisions at $\sqrt{s}=$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
2019.
Inspire Record 1742786 DOI 10.17182/hepdata.90640

Measurements of the top quark polarization and top quark pair ($\mathrm{t\bar{t}}$) spin correlations are presented using events containing two oppositely charged leptons (e$^+$e$^-$, e$^\pm\mu^\mp$, or $\mu^+\mu^-$) produced in proton-proton collisions at a center-of-mass energy of 13 TeV. The data were recorded by the CMS experiment at the LHC in 2016 and correspond to an integrated luminosity of 35.9 fb$^{-1}$. A set of parton-level normalized differential cross sections, sensitive to each of the independent coefficients of the spin-dependent parts of the $\mathrm{t\bar{t}}$ production density matrix, is measured for the first time at 13 TeV. The measured distributions and extracted coefficients are compared with standard model predictions from simulations at next-to-leading-order (NLO) accuracy in quantum chromodynamics (QCD), and from NLO QCD calculations including electroweak corrections. All measurements are found to be consistent with the expectations of the standard model. The normalized differential cross sections are used in fits to constrain the anomalous chromomagnetic and chromoelectric dipole moments of the top quark to -0.24 $<C_\text{tG}/\Lambda^{2} < $ 0.07 TeV$^{-2}$ and -0.33 $< C^{I}_\text{tG}/\Lambda^{2} < $ 0.20 TeV$^{-2}$, respectively, at 95% confidence level.

29 data tables

Figure 4, normalized differential cross section for $\cos\theta_{1}^{k}$

Figure 4, normalized differential cross section for $\cos\theta_{2}^{k}$

Figure 4, normalized differential cross section for $\cos\theta_{1}^{r}$

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Measurement of the top quark mass in the all-jets final state at $\sqrt{s} =$ 13 TeV and combination with the lepton+jets channel

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Eur.Phys.J. C79 (2019) 313, 2019.
Inspire Record 1711672 DOI 10.17182/hepdata.89051

A top quark mass measurement is performed using $35.9{\,\text {fb}^{-1}} $ of LHC proton–proton collision data collected with the CMS detector at $\sqrt{s}=13\,\text {TeV} $ . The measurement uses the ${\mathrm {t}\overline{\mathrm {t}}}$ all-jets final state. A kinematic fit is performed to reconstruct the decay of the ${\mathrm {t}\overline{\mathrm {t}}}$  system and suppress the multijet background. Using the ideogram method, the top quark mass ( $m_{\mathrm {t}}$ ) is determined, simultaneously constraining an additional jet energy scale factor ( $\text {JSF}$ ). The resulting value of $m_{\mathrm {t}} =172.34\pm 0.20\,\text {(stat+JSF)} \pm 0.70\,\text {(syst)} \,\text {GeV} $ is in good agreement with previous measurements. In addition, a combined measurement that uses the ${\mathrm {t}\overline{\mathrm {t}}}$ lepton+jets and all-jets final states is presented, using the same mass extraction method, and provides an $m_{\mathrm {t}}$ measurement of $172.26\pm 0.07\,\text {(stat+JSF)} \pm 0.61\,\text {(syst)} \,\text {GeV} $ . This is the first combined $m_{\mathrm {t}}$ extraction from the lepton+jets and all-jets channels through a single likelihood function.

1 data table

Measured top quark mass $m_{t}$


Measurements of $\mathrm{t\overline{t}}$ differential cross sections in proton-proton collisions at $\sqrt{s}=$ 13 TeV using events containing two leptons

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
JHEP 1902 (2019) 149, 2019.
Inspire Record 1703993 DOI 10.17182/hepdata.89307

Measurements of differential top quark pair $ \mathrm{t}\overline{\mathrm{t}} $ cross sections using events produced in proton-proton collisions at a centre-of-mass energy of 13 TeV containing two oppositely charged leptons are presented. The data were recorded by the CMS experiment at the CERN LHC in 2016 and correspond to an integrated luminosity of 35.9 fb$^{−1}$. The differential cross sections are presented as functions of kinematic observables of the top quarks and their decay products, the $ \mathrm{t}\overline{\mathrm{t}} $ system, and the total number of jets in the event. The differential cross sections are defined both with particle-level objects in a fiducial phase space close to that of the detector acceptance and with parton-level top quarks in the full phase space. All results are compared with standard model predictions from Monte Carlo simulations with next-to-leading-order (NLO) accuracy in quantum chromodynamics (QCD) at matrix-element level interfaced to parton-shower simulations. Where possible, parton-level results are compared to calculations with beyond-NLO precision in QCD. Significant disagreement is observed between data and all predictions for several observables. The measurements are used to constrain the top quark chromomagnetic dipole moment in an effective field theory framework at NLO in QCD and to extract $ \mathrm{t}\overline{\mathrm{t}} $ and leptonic charge asymmetries.

188 data tables

Measured absolute differential cross section at parton level as a function of $p_{T}^{t}$.

Covariance matrix of the absolute differential cross section at parton level as a function of $p_{T}^{t}$.

Measured normalised differential cross section at parton level as a function of $p_{T}^{t}$.

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Version 2
Measurement of jet substructure observables in $\mathrm{t\overline{t}}$ events from proton-proton collisions at $\sqrt{s}=$ 13TeV

The CMS collaboration Sirunyan, A. M. ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev. D98 (2018) 092014, 2018.
Inspire Record 1690148 DOI 10.17182/hepdata.84716

A measurement of jet substructure observables is presented using tt¯ events in the lepton+jets channel from proton-proton collisions at s=13  TeV recorded by the CMS experiment at the LHC, corresponding to an integrated luminosity of 35.9  fb-1. Multiple jet substructure observables are measured for jets identified as bottom, light-quark, and gluon jets, as well as for inclusive jets (no flavor information). The results are unfolded to the particle level and compared to next-to-leading-order predictions from powheg interfaced with the parton shower generators pythia 8 and herwig 7, as well as from sherpa 2 and Dire 2. A value of the strong coupling at the Z boson mass, αS(mZ)=0.115-0.013+0.015, is extracted from the substructure data at leading-order plus leading-log accuracy.

132 data tables

Distribution of $\lambda_{0}^{0}$ (N) reconstructed from charged particles with pt > 1 GeV, unfolded to the particle level.

Distribution of $\lambda_{0}^{2}$ ($p_{T}^{d,*})$ reconstructed from charged particles with pt > 1 GeV, unfolded to the particle level.

Distribution of $\lambda_{0.5}^{1}$ (LHA) reconstructed from charged particles with pt > 1 GeV, unfolded to the particle level.

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Measurement of the top quark mass with lepton+jets final states using $\mathrm {p}$ $\mathrm {p}$ collisions at $\sqrt{s}=13\,\text {TeV} $

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Eur.Phys.J. C78 (2018) 891, 2018.
Inspire Record 1671499 DOI 10.17182/hepdata.85702

The mass of the top quark is measured using a sample of ${{\text {t}}\overline{{\text {t}}}}$ events collected by the CMS detector using proton-proton collisions at $\sqrt{s}=13$ $\,\text {TeV}$ 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 $\,\text {fb}^{-1}$ . For each event the mass is reconstructed from a kinematic fit of the decay products to a ${{\text {t}}\overline{{\text {t}}}}$ 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 ${\text {q}} \overline{{\text {q}}} ^\prime $ 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\,\text {(stat+JSF)} \pm 0.62\,\text {(syst)} \,\text {GeV} $ . The dependence of this result on the kinematic properties of the event is studied and compared to predictions of different models of ${{\text {t}}\overline{{\text {t}}}}$ production, and no indications of a bias in the measurements are observed.

1 data table

Measured top quark mass $m_{t}$


Version 2
Measurement of differential cross sections for the production of top quark pairs and of additional jets in lepton+jets events from pp collisions at $\sqrt{s} =$ 13 TeV

The CMS collaboration Sirunyan, Albert M ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
Phys.Rev. D97 (2018) 112003, 2018.
Inspire Record 1663958 DOI 10.17182/hepdata.85696

Differential and double-differential cross sections for the production of top quark pairs in proton-proton collisions at s=13  TeV are measured as a function of kinematic variables of the top quarks and the top quark-antiquark (tt¯) system. In addition, kinematic variables and multiplicities of jets associated with the tt¯ production are measured. This analysis is based on data collected by the CMS experiment at the LHC in 2016 corresponding to an integrated luminosity of 35.8  fb-1. The measurements are performed in the lepton+jets decay channels with a single muon or electron and jets in the final state. The differential cross sections are presented at the particle level, within a phase space close to the experimental acceptance, and at the parton level in the full phase space. The results are compared to several standard model predictions that use different methods and approximations. The kinematic variables of the top quarks and the tt¯ system are reasonably described in general, though none predict all the measured distributions. In particular, the transverse momentum distribution of the top quarks is more steeply falling than predicted. The kinematic distributions and multiplicities of jets are adequately modeled by certain combinations of next-to-leading-order calculations and parton shower models.

239 data tables

Absolute cross section at particle level as a function of $p_\text{T}(\text{t}_\text{h})$.

Covariance matrix of absolute cross section at particle level as a function of $p_\text{T}(\text{t}_\text{h})$.

Absolute cross section at particle level as a function of $|y(\text{t}_\text{h})|$.

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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.
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.

18 data tables

The measured normalized $t\bar{t}$ double-differential cross sections in different bins of $y(t)$ and $p_{T}(t)$, along with their relative statistical and systematic uncertainties expressed as percentages.

The correlation matrix of statistical uncertainties for the normalized $t\bar{t}$ double-differential cross sections as a function of $y(t)$ and $p_{T}(t)$. The values are expressed as percentages. For bin indices see Table 5.

Sources and values of the relative systematic uncertainties in percent of the measured normalized $t\bar{t}$ double-differential cross sections as a function of $y(t)$ and $p_{T}(t)$. For bin indices see Table 5.

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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.
Eur.Phys.J. C77 (2017) 172, 2017.
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 $\pm$ 8 (stat) $\pm$ 37 (syst) $\pm$ 21 (lumi) pb, in agreement with the expectation from the standard model.

3 data tables

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.


Measurement of differential cross sections for top quark pair production using the lepton+jets final state in proton-proton collisions at 13 TeV

The CMS collaboration Khachatryan, Vardan ; Sirunyan, Albert M ; Tumasyan, Armen ; et al.
Phys.Rev. D95 (2017) 092001, 2017.
Inspire Record 1491950 DOI 10.17182/hepdata.76554

Differential and double-differential cross sections for the production of top quark pairs in proton-proton collisions at 13 TeV are measured as a function of jet multiplicity and of kinematic variables of the top quarks and the top quark-antiquark system. This analysis is based on data collected by the CMS experiment at the LHC corresponding to an integrated luminosity of 2.3  fb−1. The measurements are performed in the lepton+jets decay channels with a single muon or electron in the final state. The differential cross sections are presented at particle level, within a phase space close to the experimental acceptance, and at parton level in the full phase space. The results are compared to several standard model predictions.

164 data tables

Absolute cross section at particle level.

Covariance matrix of absolute cross section at particle level.

Absolute cross section at particle level.