Date

Measurement of Z$γ$ production in proton-proton collisions at $\sqrt{s}$ = 13.6 TeV and constraints on neutral triple gauge couplings

The CMS collaboration Hayrapetyan, Aram ; Makarenko, Vladimir ; Tumasyan, Armen ; et al.
CMS-SMP-24-002, 2025.
Inspire Record 3091053 DOI 10.17182/hepdata.166443

A measurement of the Z$γ$ production cross section in proton-proton collisions at a center-of-mass energy of 13.6 TeV is presented. Data corresponding to an integrated luminosity of 34.8 fb$^{-1}$, collected by the CMS experiment at the LHC in 2022 are used. Events with an oppositely charged pair of muons or electrons, with an invariant mass corresponding to a Z boson, together with an isolated photon are selected. The measured fiducial cross section for the combined electron and muon channels is 1.896 $\pm$ 0.033 (stat) $\pm$ 0.05 (syst) $\pm$ 0.006 (theo) pb, in agreement with the standard model prediction of 1.922 $\pm$ 0.094 pb. Constraints on neutral triple gauge couplings generated by dimension-8 operators in a recently proposed effective field theory framework are determined for the first time.

4 data tables

Histograms represent the post-fit distribution of $mass_{\mu^+\mu^-\gamma}$. The number of signal and background are associated with the total uncertainty, and the number of data events are associated with the poisson errors. The last bins include overflow events.

Histograms represent the post-fit distribution of $mass_{e^+e^-\gamma}$. The number of signal and background are associated with the total uncertainty, and the number of data events are associated with the poisson errors. The last bins include overflow events.

Expected and observed 95% CL limits on nTGC parameters for the combination of the measurements in the electron and muon channels. The first three rows show the results using the VPM that preserves only the U(1)EM symmetry, while the last three rows show the results from the GSPM that preserves the SU(2)L x U(1)Y symmetry. Corresponding to Table 3 in the paper.

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Measurements of electroweak production of a photon in association with two jets in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Makarenko, Vladimir ; Tumasyan, Armen ; et al.
CMS-SMP-19-005, 2025.
Inspire Record 3088047 DOI 10.17182/hepdata.167074

The first observation of electroweak production of a photon in association with two forward jets in proton-proton collisions is presented. The measurement uses data recorded by the CMS experiment at the LHC during 2016$-$2018 at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb$^{-1}$. The analysis is performed in a region enriched in photon production via vector boson fusion, with a requirement on the transverse momentum of the photon to exceed 200 GeV. The cross section is measured to be 202$^{+36}_{-32}$ fb, at a significance with respect to the null hypothesis that exceeds five standard deviations. This is in agreement with the standard model prediction of 177$^{+13}_{-12}$ fb. Differential cross sections are measured as a function of various observables. Limits are set on dimension-6 effective field theory operators that contribute to the WW$γ$ interaction. The observed 95% confidence intervals for the corresponding Warsaw basis Wilson coefficients $c_\mathrm{W}$ and $c_\mathrm{HWB}$ are [$-$0.11, 0.16] and [$-$1.6, 1.5], respectively.

12 data tables

Summary of uncertainties affecting the measurement as extracted from the fit to data. The total uncertainty is obtained by adding individual contributions in quadrature.

The rapidity gap fraction as a function of $p_{\mathrm{T}^{veto}}$ in data and simulated samples for EW $\gamma$jj and QCD $\gamma$jj. The black points with error bars represent the data and their statistical uncertainties. The theory prediction, calculated using Madgraph5_aMC@NLO version 2.6.5 at NLO in QCD together with PYTHIA version 8.240, as well as MC statistical uncertainties are shown by the colored band.

Normalized differential cross sections, compared with the SM predictions, as a function of the absolute value of pseudorapidity of the leading jet in transverse momentum. The SM predictions are obtained using Madgraph5_aMC@NLO version 2.6.5 at NLO in QCD with PYTHIA version 8.240

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Search for a new neutral gauge boson produced in association with one or two b jets and decaying into a pair of muons in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Chekhovsky, Vladimir ; Hayrapetyan, Aram ; Makarenko, Vladimir ; et al.
CMS-EXO-22-006, 2025.
Inspire Record 3084285 DOI 10.17182/hepdata.165428

A search for a new neutral gauge boson, Z', produced in association with one or two jets, including at least one b jet, and decaying into a pair of muons is presented. The analysis uses proton-proton collision data collected with the CMS detector at $\sqrt{s}$ = 13 TeV, corresponding to an integrated luminosity of 138 fb$^{-1}$. No significant deviation from background expectations is observed. Upper limits at 95% confidence level on the product of cross section, branching fraction to dimuons, acceptance, and efficiency, from 0.2 to 2 fb, are set for Z' boson masses between 125 and 350 GeV. Process-dependent products of acceptance and efficiency, and model-independent limits on the signal yield are provided. These are the only results to date in the 125$-$200 GeV mass range and the most stringent for b quark fusion production modes in the 200$-$350 GeV range, complementing inclusive Z' boson searches.

13 data tables

Distributions of $m_{\ell\ell}$ in the $\mathrm{SR_{b}^{mm}}$ SR. Events are divided by the bin width. Simulated signal shapes for $Z'$ boson masses of 125, 200, and 350 GeV are shown. The "Stat + syst" band shows the envelope of the fit variations with statistical uncertainties. The ratio of the nominal MC background values (dashed line) and data to the ABCD prediction is shown as a dashed line in the ratio plot. The MC background uncertainties are not shown for visual clarity.

Distributions of $m_{\ell\ell}$ in the $\mathrm{SR_{b+\textrm{j}/b}^{mm}}$ SR. Events are divided by the bin width. Simulated signal shapes for $Z'$ boson masses of 125, 200, and 350 GeV are shown. The "Stat + syst" band shows the envelope of the fit variations with statistical uncertainties. The ratio of the nominal MC background values (dashed line) and data to the ABCD prediction is shown as a dashed line in the ratio plot. The MC background uncertainties are not shown for visual clarity.

Data vs. the ABCD method background prediction for 2016 in $\mathrm{SR_{b}^{mm}}$. Events are divided by the bin width, hence fractional data counts. Error bars show statistical uncertainties of data. The blue band shows the propagated uncertainty of all individual fit variations in a given bin, which we consider to be uncorrelated. The lower panels show the ratio of the observed data to the background estimation.

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Jet fragmentation function and groomed substructure of bottom quark jets in proton-proton collisions at 5.02 TeV

The CMS collaboration Chekhovsky, Vladimir ; Hayrapetyan, Aram ; Makarenko, Vladimir ; et al.
CMS-HIN-24-005, 2025.
Inspire Record 3083430 DOI 10.17182/hepdata.156184

A measurement of the substructure of bottom quark jets (b jets) in proton-proton (pp) collisions is presented. The measurement uses data collected in pp collisions at $\sqrt{s}$ = 5.02 TeV recorded by the CMS experiment in 2017, corresponding to an integrated luminosity of 301$^{-1}$. An algorithm to identify and cluster the charged decay daughters of b hadrons is developed for this analysis, which facilitates the exposure of the gluon radiation pattern of b jets using iterative Cambridge-Aachen declustering. The soft-drop-groomed jet radius, $R_\mathrm{g}$, and momentum balance, $z_\mathrm{g}$, of b quark jets are presented. These observables can be used to test perturbative quantum chromodynamics predictions that account for mass effects. Because the b hadron is partially reconstructed from its charged decay daughters, only charged particles are used for the jet substructure studies. In addition, a jet fragmentation function, $z_\text{b,ch}$, is measured, which is defined as the distribution of the ratio of the transverse momentum ($p_\mathrm{T}$) of the partially reconstructed b hadron with respect to the charged-particle component of the jet $p_\mathrm{T}$. The substructure variable distributions are unfolded to the charged-particle level. The b jet substructure is compared to the substructure of jets in an inclusive jet sample that is dominated by light-quark and gluon jets in order to assess the role of the b quark mass. A strong suppression of emissions at small $R_\mathrm{g}$ values is observed for b jets when compared to inclusive jets, consistent with the dead-cone effect. The measurement is also compared with theoretical predictions from Monte Carlo event generators. This is the first substructure measurement of b jets that clusters together the b hadron decay daughters.

7 data tables

The groomed jet radius distribution of inclusive jets.

The groomed momentum balance distribution of inclusive jets.

The groomed jet radius distribution of b jets.

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Characterizing the initial state and dynamical evolution in XeXe and PbPb collisions using multiparticle cumulants

The CMS collaboration Hayrapetyan, Aram ; Makarenko, Vladimir ; Tumasyan, Armen ; et al.
CMS-HIN-24-004, 2025.
Inspire Record 3075174 DOI 10.17182/hepdata.161536

For the first time, correlations among mixed-order moments of two or three flow harmonics $-$($v_{n}^{k},v_{m}^{l}$) and ($v_{n}^{k},v_{m}^{l}, v_{p}^{q}$), with $k$, $l$, and $q$ denoting the respective orders$-$are measured in xenon-xenon (XeXe) collisions and compared with lead-lead (PbPb) results, providing a novel probe of collective behavior in heavy ion collisions. These measurements compare a nearly spherical, doubly-magic ${}^{208}$Pb nucleus to a triaxially deformed ${}^{129}$Xe nucleus, emphasizing the sensitivity to dynamic nuclear deformation. The dependence of these results ($v_{n}$, $n$ = 2, 3, 4) on the shape and size of the nuclear overlap region is studied. Comparisons between $v_{2}$, $v_{3}$, and $v_{4}$ demonstrate the importance of $v_{3}$ and $v_{4}$ in exploring the nonlinear hydrodynamic response of the quark-gluon plasma (QGP) to the initial spatial anisotropy. The results constrain initial-state model parameters that influence the evolution of the QGP. The CMS detector was used to collect XeXe and PbPb data at nucleon-nucleon center-of-mass energies of $\sqrt{s_\mathrm{NN}}$ = 5.44 and 5.36 TeV, respectively. Correlations are extracted using multiparticle mixed-harmonic cumulants (up to eight-particle cumulants) with charged particles in the pseudorapidity range $\lvertη\rvert$$\lt$ 2.4 and transverse momentum range 0.5 $\lt$$p_\mathrm{T}$$\lt$ 3 GeV/$c$.

25 data tables

Two-particle correlations v_{2}{2} as a function of centrality in XeXe and PbPb collisions and ratios of XeXe/PbPb.

Two-particle correlations v_{3}{2} as a function of centrality in XeXe and PbPb collisions and ratios of XeXe/PbPb.

v_{2}{4}/v_{2}{2} as a function of centrality in XeXe and PbPb collisions and ratios of XeXe/PbPb.

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Search for dijet resonances with data scouting in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Makarenko, Vladimir ; Tumasyan, Armen ; et al.
CMS-EXO-23-004, 2025.
Inspire Record 3073143 DOI 10.17182/hepdata.159438

A search is presented for narrow resonances, with a mass between 0.6 and 1.8 TeV, decaying to pairs of jets, in proton-proton collisions at $\sqrt{s}$ = 13 TeV. The search is performed using dijets that are reconstructed, selected, and recorded in a compact form by the high-level trigger in a technique referred to as "data scouting", from data collected in 2016$-$2018 corresponding to an integrated luminosity of 177 fb$^{-1}$. The dijet mass spectra are well described by a smooth parameterization, and no significant evidence for the production of new particles is observed. Model-independent upper limits are presented on the product of the cross section, branching fraction, and acceptance for the individual cases of narrow quark-quark, quark-gluon, and gluon-gluon resonances, and are compared to the predictions from a variety of models of narrow dijet resonance production. The upper limit on the coupling of a dark matter mediator to quarks is presented as a function of the mediator mass. The sensitivity of this search goes beyond what is expected from statistical scaling with the integrated luminosity alone, as a consequence of the use of fewer parameters in the background function within a more robust statistical procedure.

8 data tables

Observed differential dijet spectrum using the 2016 data.

Observed differential dijet spectrum using the 2017 data.

Observed differential dijet spectrum using the 2018 data.

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Measurement of the ratio of the B$_\mathrm{c}^+$$\to$ J/$ψ$$τ^+ν_τ$ and B$_\mathrm{c}^+$$\to$ J/$ψ$$μ^+ν_μ$ branching fractions using three-prong $τ$ lepton decays

The CMS collaboration Chekhovsky, Vladimir ; Hayrapetyan, Aram ; Makarenko, Vladimir ; et al.
CMS-BPH-23-001, 2025.
Inspire Record 3072961 DOI 10.17182/hepdata.166008

The ratio between the B$_\mathrm{c}^+$$\to$ J/$ψ$$τ^+ν_τ$ and B$_\mathrm{c}^+$$\to$ J/$ψ$$μ^+ν_μ$ branching fractions is measured using a data sample of proton-proton collisions collected by CMS at a center-of-mass energy of 13 TeV in the years 2016$-$2018 and corresponding to an integrated luminosity of 138 fb$^{-1}$. The J$/ψ$ meson is identified through its J$/ψ$$\to$$μ^+μ^-$ decay and the tau lepton is reconstructed in the hadronic three-prong final state. The measured ratio of branching fractions in this tau decay mode, $\mathcal{R}^\text{had}_{\mathrm{J}/ψ}$ = 1.04$_{-0.44}^{+0.50}$, is combined with the previous analysis based on the $τ^+$$\to$$μ^+ν_μ\barν_τ$ leptonic decay channel, leading to $\mathcal{R}_{\mathrm{J}/ψ}$ = 0.49 $\pm$ 0.26. As this result is consistent with the standard model prediction of 0.258 $\pm$ 0.004, no evidence of lepton flavor universality violation is found.

1 data table

Observation of tWZ production at the CMS experiment

The CMS collaboration Hayrapetyan, Aram ; Makarenko, Vladimir ; Tumasyan, Armen ; et al.
CMS-TOP-24-009, 2025.
Inspire Record 3072016 DOI 10.17182/hepdata.158454

The first observation of single top quark production in association with a W and a Z boson in proton-proton collisions is reported. The analysis uses data at center-of-mass energies of 13 and 13.6 TeV recorded with the CMS detector at the CERN LHC, corresponding to a total integrated luminosity of 200 fb$^{-1}$. Events with three or four charged leptons, which can be electrons or muons, are selected. Advanced machine-learning algorithms and improved reconstruction methods, compared to an earlier analysis, result in an unprecedented sensitivity to tWZ production. The measured cross sections for tWZ production are 248 $\pm$ 52 fb and 244 $\pm$ 74 fb for $\sqrt{s}$ =13 and 13.6 TeV, respectively. The signal is established with a statistical significance of 5.8 standard deviations, with 3.5 expected, compared to the background-only hypothesis.

6 data tables

Distributions in the ML output scores for the tWZ output node in the 3l SR after a fit to the data.

Distributions in the ML output scores for the ttZ output node in the 3l SR after a fit to the data.

Distributions in the ML output scores for the tWZ output node in the 4l SR after a fit to the data.

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Vector boson scattering and anomalous quartic couplings in final states with $\ellν$qq or $\ell\ell$qq plus jets using proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Makarenko, Vladimir ; Tumasyan, Armen ; et al.
CMS-SMP-22-011, 2025.
Inspire Record 3006061 DOI 10.17182/hepdata.165281

A measurement is presented of the electroweak vector boson scattering production of ZV (V = W, Z) boson pairs associated with two jets in proton-proton collisions at a center-of-mass energy of 13 TeV. The data, corresponding to an integrated luminosity of 138 fb$^{-1}$, were collected at the CERN LHC with the CMS detector during the 2016$-$2018 data-taking period. The analysis targets final states with a pair of isolated electrons or muons from Z boson decays and three or four jets, depending on the momentum of the vector boson that decays into quarks. Signal strength is measured for events characterized by a large invariant mass of two forward jets with a wide pseudorapidity gap between them. The electroweak production of ZV in association with two jets is measured with an observed (expected) significance of 1.3 (1.8) standard deviations. A combination of the analyses of ZV channel and the previously published WV channel in the lepton plus jets final state places constraints on effective field theory parameters that describe anomalous electroweak production of WW, WZ, and ZZ boson pairs in association with two jets. Several world best limits are set on anomalous quartic gauge couplings in terms of dimension-8 standard model effective field theory operators.

10 data tables

Distributions of DNN score for the data and post-fit backgrounds (stacked histograms), in the SRs of the ZV channel for the b tag (left) and the b veto (right) channels, for the resolved (merged) category in the first (second) row. The post-fit VBS EW ZV signal is shown overlaid as a red solid line. The overflow is included in the last bin. The lower panels show the ratios of the data to the pre-fit background prediction and post-fit background yield as red open squares and blue points, respectively. The gray band in the lower panels indicates the systematic component of the post-fit background uncertainty. The vertical bars on the data points represent statistical uncertainties. The last bin includes overflow.

Distributions of DNN score for the data and post-fit backgrounds (stacked histograms), in the SRs of the ZV channel for the b tag (left) and the b veto (right) channels, for the resolved (merged) category in the first (second) row. The post-fit VBS EW ZV signal is shown overlaid as a red solid line. The overflow is included in the last bin. The lower panels show the ratios of the data to the pre-fit background prediction and post-fit background yield as red open squares and blue points, respectively. The gray band in the lower panels indicates the systematic component of the post-fit background uncertainty. The vertical bars on the data points represent statistical uncertainties. The last bin includes overflow.

Distributions of DNN score for the data and post-fit backgrounds (stacked histograms), in the SRs of the ZV channel for the b tag (left) and the b veto (right) channels, for the resolved (merged) category in the first (second) row. The post-fit VBS EW ZV signal is shown overlaid as a red solid line. The overflow is included in the last bin. The lower panels show the ratios of the data to the pre-fit background prediction and post-fit background yield as red open squares and blue points, respectively. The gray band in the lower panels indicates the systematic component of the post-fit background uncertainty. The vertical bars on the data points represent statistical uncertainties. The last bin includes overflow.

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Measurement of the dineutrino system kinematic variables in dileptonic top quark pair production in proton-proton collisions at$\sqrt{s}$ = 13 TeV

The CMS collaboration Chekhovsky, Vladimir ; Hayrapetyan, Aram ; Makarenko, Vladimir ; et al.
CMS-TOP-24-001, 2025.
Inspire Record 3006250 DOI 10.17182/hepdata.153302

Differential top quark pair production cross sections are measured in the dilepton final states e$^+$e$^-$, $μ^+μ^-$, and e$^\pmμ^\mp$, as a function of kinematic variables of the two-neutrino system: the transverse momentum $p_\mathrm{T}^{νν}$ of the dineutrino system, the minimum distance in azimuthal angle between $\vec{p}_\mathrm{T}^{\,νν}$ and leptons, and in two dimensions in bins of both observables. The measurements are performed using CERN LHC proton-proton collisions at $\sqrt{s}$ = 13 TeV, recorded by the CMS detector between 2016 and 2018, corresponding to an integrated luminosity of 138 fb$^{-1}$. The measured cross sections are unfolded to the particle level using an unregularized least squares method. Results are compared with predictions by the standard model of particle physics, and found to be in agreement with theoretical calculations as well as Monte Carlo simulations.

43 data tables

Data and MC simulation yields after the event selection, combined for all data-taking periods and split by channels. The uncertainties on the expected yields include systematic and statistical uncertainties. The relative contribution in percent of each process to the total expected yield of a channel is given in parentheses.

Observed (black markers) and expected distributions of leading lepton $p_{T}$ after event selection. The hatched (grey) areas denote the systematic (total) uncertainties in the expected yields. Events from all data-taking periods and all channels are combined. The lower panel of each plot shows the ratio between observed and expected distributions. The last bin includes all events above the plotted range. The entry Background corresponds to the sum of all the SM predictions.

Observed (black markers) and expected distributions of leading jet $p_{T}$ after event selection. The hatched (grey) areas denote the systematic (total) uncertainties in the expected yields. Events from all data-taking periods and all channels are combined. The lower panel of each plot shows the ratio between observed and expected distributions. The last bin includes all events above the plotted range. The entry Background corresponds to the sum of all the SM predictions.

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