Date

Search for heavy neutral resonances decaying to tau lepton pairs in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
CMS-EXO-21-016, 2024.
Inspire Record 2856405 DOI 10.17182/hepdata.155459

A search for heavy neutral gauge bosons (Z') decaying into a pair of tau leptons is performed in proton-proton collisions at $\sqrt{s}$ = 13 TeV at the CERN LHC. The data were collected with the CMS detector and correspond to an integrated luminosity of 138 fb$^{-1}$. The observations are found to be in agreement with the expectation from standard model processes. Limits at 95% confidence level are set on the product of the Z' production cross section and its branching fraction to tau lepton pairs for a range of Z' boson masses. For a narrow resonance in the sequential standard model scenario, a Z' boson with a mass below 3.5 TeV is excluded. This is the most stringent limit to date from this type of search.

23 data tables

Cutflow for signal samples in the hadronic di-tau channel for 2016 signal samples. Each entry other than the total is the relative efficiency with respect to the previous selection.

Cutflow for signal samples in the hadronic di-tau channel for 2017 signal samples. Each entry other than the total is the relative efficiency with respect to the previous selection.

Cutflow for signal samples in the hadronic di-tau channel for 2018 signal samples. Each entry other than the total is the relative efficiency with respect to the previous selection.

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Model-agnostic search for dijet resonances with anomalous jet substructure in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Chekhovsky, Vladimir ; Hayrapetyan, Aram ; Makarenko, Vladimir ; et al.
CMS-EXO-22-026, 2024.
Inspire Record 2856408 DOI 10.17182/hepdata.156054

This paper presents a model-agnostic search for narrow resonances in the dijet final state in the mass range 1.8-6 TeV. The signal is assumed to produce jets with substructure atypical of jets initiated by light quarks or gluons, with minimal additional assumptions. Search regions are obtained by utilizing multivariate machine-learning methods to select jets with anomalous substructure. A collection of complementary anomaly detection methods - based on unsupervised, weakly supervised, and semisupervised algorithms - are used in order to maximize the sensitivity to unknown new physics signatures. These algorithms are applied to data corresponding to an integrated luminosity of 138 fb$^{-1}$, recorded by the CMS experiment at the LHC, at a center-of-mass energy of 13 TeV. No significant excesses above background expectations are seen. Exclusion limits are derived on the production cross section of benchmark signal models varying in resonance mass, jet mass, and jet substructure. Many of these signatures have not been previously sought, making several of the limits reported on the corresponding benchmark models the first ever. When compared to benchmark inclusive and substructure-based search strategies, the anomaly detection methods are found to significantly enhance the sensitivity to a variety of models.

11 data tables

Exclusion limits on the production cross section of the Q* -> q Wprime model from the different anomaly detection methods

Exclusion limits on the production cross section of the X -> Y Yprime model from the different anomaly detection methods

Exclusion limits on the production cross section of the Wprime -> Bprime t model from the different anomaly detection methods

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Measurement of the inclusive WZ production cross section in pp collisions at $\sqrt{s}$ = 13.6 TeV

The CMS collaboration Hayrapetyan, Aram ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
CMS-SMP-24-005, 2024.
Inspire Record 2855546 DOI 10.17182/hepdata.155693

The inclusive WZ production cross section is measured in proton-proton collisions at a centre-of-mass energy of 13.6 TeV, using data collected during 2022 with the CMS detector, corresponding to an integrated luminosity of 34.7 fb$^{-1}$. The measurement uses multileptonic final states and a simultaneous likelihood fit to the number of events in four different lepton flavour categories: eee, ee$\mu$, $\mu\mu $e, and $\mu\mu\mu$. The selection is optimized to minimize the number of background events, and relies on an efficient prompt lepton discrimination strategy. The WZ production cross section is measured in a phase space defined within a 30 GeV window around the Z boson mass, as $\sigma_{\text{total}}$(pp$\to$WZ) = 55.2$\pm$1.2 (stat) $\pm$1.2 (syst) $\pm$0.8 (lumi) $\pm$0.1 (theo) pb. In addition, the cross section is measured in a fiducial phase space closer to the detector-level requirements. All the measurements presented in this paper are in agreement with standard model predictions.

8 data tables

Number of events for the different lepton flavour categories in the ZZ control region accounting for the fit to data. The hatched band includes all systematic uncertainties in the MC prediction. The vertical bars of the data account for the statistical uncertainty. The ratio panels show the ratio between data (black markers) with respect to the total prediction after the fit to data. Processes with a small contribution to this region are grouped in the ``Other" category

Number of events for the different lepton flavour categories in the ttZ control region accounting for the fit to data. The hatched band includes all systematic uncertainties in the MC prediction. The vertical bars of the data account for the statistical uncertainty. The ratio panels show the ratio between data (black markers) with respect to the total prediction after the fit to data. Processes with a small contribution to this region are grouped in the ``Other" category

Number of events for the different lepton flavour categories in the X+#gamma control region accounting for the fit to data. The hatched band includes all systematic uncertainties in the MC prediction. The vertical bars of the data account for the statistical uncertainty. The ratio panels show the ratio between data (black markers) with respect to the total prediction after the fit to data. Processes with a small contribution to this region are grouped in the ``Other" category

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Search for heavy neutral Higgs bosons A and H in the $\mathrm{t\bar{t}}$Z channel in proton-proton collisions at 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
CMS-B2G-23-006, 2024.
Inspire Record 2854935 DOI 10.17182/hepdata.150023

A direct search for new heavy neutral Higgs bosons A and H in the $\mathrm{t\bar{t}}$Z channel is presented, targeting the process pp $\to$ A $\to$ ZH with H $\to$$\mathrm{t\bar{t}}$. For the first time, the channel with decays of the Z boson to muons or electrons in association with all-hadronic decays of the $\mathrm{t\bar{t}}$ system is targeted. The analysis uses proton-proton collision data collected at the CERN LHC with the CMS experiment at $\sqrt{s}$ = 13 TeV, which correspond to an integrated luminosity of 138 fb$^{-1}$. No signal is observed. Upper limits on the product of the cross section and branching fractions are derived for narrow resonances A and H with masses up to 2100 and 2000 GeV, respectively, assuming A boson production through gluon fusion. The results are also interpreted within two-Higgs-doublet models, complementing and substantially extending the reach of previous searches.

14 data tables

Distributions of p_T(Z) × ∆m in the SR after the fit to data with a (mA , mH) signal hypothesis of (1000, 350) GeV. The post-fit signal yields are compatible with zero events in all bins. The pre-fit signal is arbitrarily scaled and therefore omitted.

Distributions of p_T(Z) × ∆m in the SR after the fit to data with a (mA , mH) signal hypothesis of (1000, 850) GeV. The pre-fit signal is arbitrarily scaled and therefore omitted.

Expected 95% CL upper limits on the production cross section times branching ratio of the A → ZH → Ztt process in the (mA , mH) plane.

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Constraints on standard model effective field theory for a Higgs boson produced in association with W or Z bosons in the H$\to\mathrm{b\bar{b}}$ decay channel in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Chekhovsky, Vladimir ; Hayrapetyan, Aram ; Makarenko, Vladimir ; et al.
CMS-HIG-23-016, 2024.
Inspire Record 2852160 DOI 10.17182/hepdata.155497

A standard model effective field theory (SMEFT) analysis with dimension-six operators probing nonresonant new physics effects is performed in the Higgs-strahlung process, where the Higgs boson is produced in association with a W or Z boson, in proton-proton collisions at a center-of-mass energy of 13 TeV. The final states in which the W or Z boson decays leptonically and the Higgs boson decays to a pair of bottom quarks are considered. The analyzed data were collected by the CMS experiment between 2016 and 2018 and correspond to an integrated luminosity of 138 fb$^{-1}$. An approach designed to simultaneously optimize the sensitivity to Wilson coefficients of multiple SMEFT operators is employed. Likelihood scans as functions of the Wilson coefficients that carry SMEFT sensitivity in this final state are performed for different expansions in SMEFT. The results are consistent with the predictions of the standard model.

32 data tables

Summary of results in terms of best fit value of the Wilson coefficients and the intervals where the test statistic is below 1 and 4, with up to the linear and quadratic terms in the SMEFT parameterization.

Profiled limits on the energy scale $\Lambda$ for three different assumptions for each Wilson coefficient while fixing the other Wilson coefficients to their SM values with up to the linear and quadratic terms in SMEFT parameterization.

Observed two-dimensional likelihood scans for $c_{Hq}^{(1)}$ vs. $c_{Hq}^{(3)}$ while allowing the other coefficients to float freely at each point of the sca.

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Search for rare decays of the Z and Higgs bosons to a J/$\psi$ or $\psi$(2S) meson and a photon in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
CMS-SMP-22-012, 2024.
Inspire Record 2851464 DOI 10.17182/hepdata.154897

A search is presented for rare decays of the Z and Higgs bosons to a photon and a J/$\psi$ or a $\psi$(2S) meson, with the charmonium state subsequentially decaying to a pair of muons. The data set corresponds to an integrated luminosity of 123 fb$^{-1}$ of proton-proton collisions at a center-of-mass energy of 13 TeV collected with the CMS detector at the LHC. No evidence for branching fractions of these rare decay channels larger than predicted in the standard model is observed. Upper limits at 95% confidence level are set: $\mathcal{B}$(H $\to$ J/$\psi \gamma$) $\lt$ 2.6 $\times$ 10$^{-4}$, $\mathcal{B}$(H$\to$ $\psi$(2S)$\gamma$) $\lt$ 9.9 $\times$ 10$^{-4}$, $\mathcal{B}$(Z$\to$ J/$\psi$$\gamma$) $\lt$ 0.6 $\times$ 10$^{-6}$, and $\mathcal{B}$(Z$\to$$\psi$(2S)$\gamma$) $\lt$ 1.3 $\times$ 10$^{-6}$. The ratio of the Higgs boson coupling modifiers $\kappa_\mathrm{c}/\kappa_\gamma$ is constrained to be in the interval ($-$157, $+$199) at 95% confidence level. Assuming $\kappa_\gamma=1$, this interval becomes ($-$166, $+$208).

11 data tables

Invariant mass distribution of final state particles in SR1 ggF-HP category ($\text{H}\to\text{J}/\psi\gamma$ signal)

Invariant mass distribution of final state particles in SR1 ggF-LP category ($\text{H}\to\text{J}/\psi\gamma$ signal)

Invariant mass distribution of final state particles in SR1 VBF category ($\text{H}\to\text{J}/\psi\gamma$ signal)

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Angular analysis of the B$^0$$\to$ K$^*$(892)$^0\mu^+\mu^-$ decay in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
CMS-BPH-21-002, 2024.
Inspire Record 2850101 DOI 10.17182/hepdata.154898

A full set of optimized observables is measured in an angular analysis of the decay B$^0$$\to$ K$^*$(892)$^0\mu^+\mu^-$ using a sample of proton-proton collisions at $\sqrt{s}$ = 13 TeV, collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 140 fb$^{-1}$. The analysis is performed in six bins of the squared invariant mass of the dimuon system, $q^2$, over the range 1.1 $\lt$$q^2$$\lt$ 16 GeV$^2$. The results are among the most precise experimental measurements of the angular observables for this decay and are compared to a variety of predictions based on the standard model.

15 data tables

Results for the $F_\mathrm{L}$ angular observable. The first uncertainties are statistical and the second systematic.

Results for the $P_1$ angular observable. The first uncertainties are statistical and the second systematic.

Results for the $P_2$ angular observable. The first uncertainties are statistical and the second systematic.

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Search for a heavy resonance decaying into a Z and a Higgs boson in events with an energetic jet and two electrons, two muons, or missing transverse momentum in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
CMS-B2G-23-008, 2024.
Inspire Record 2847311 DOI 10.17182/hepdata.153397

A search is presented for a heavy resonance decaying into a Z boson and a Higgs (H) boson. The analysis is based on data from proton-proton collisions at a centre-of-mass energy of 13 TeV corresponding to an integrated luminosity of 138 fb$^{-1}$, recorded with the CMS experiment in the years 2016-2018. Resonance masses between 1.4 and 5 TeV are considered, resulting in large transverse momenta of the Z and H bosons. Final states that result from Z boson decays to pairs of electrons, muons, or neutrinos are considered. The H boson is reconstructed as a single large-radius jet, recoiling against the Z boson. Machine-learning flavour-tagging techniques are employed to identify decays of a Lorentz-boosted H boson into pairs of charm or bottom quarks, or into four quarks via the intermediate H $\to$ WW* and ZZ* decays. The analysis targets H boson decays that were not generally included in previous searches using the H $\to$$\mathrm{b\bar{b}}$ channel. Compared with previous analyses, the sensitivity for high resonance masses is improved significantly in the channel where at most one b quark is tagged.

8 data tables

The product of signal acceptance and efficiency for signal events as a function of $m_{Z'}$ for the charged-lepton and neutrino channels in the SR. The efficiency is calculated with respect to Z boson decays to charged leptons and neutrinos for the charged-lepton and neutrino channels, respectively. For comparison, the results from the $\leq$ 1 b category of the previous CMS search in the ZH channel are shown as dashed lines.

Distributions in $m_{Z'}^{rec}$ for data in the SRs, together with fits of the background functions under the background-only hypothesis for the muon channel. The number of observed events in each bin is divided by the bin width. The signal predictions are shown for different Z' boson masses, normalized to an arbitrary cross section of 1 fb. In the panels below the distributions, the ratios of data to the background function are displayed. The shaded green areas represent the statistical uncertainty from the fit. The $\chi^2$ values per number of degrees of freedom ($\chi^2$/n.d.f.) and the corresponding $p$-values are provided for each fit.

Distributions in $m_{Z'}^{T}$ for data in the SRs, together with fits of the background functions under the background-only hypothesis for the invisible channel. The number of observed events in each bin is divided by the bin width. The signal predictions are shown for different Z' boson masses, normalized to an arbitrary cross section of 1 fb. In the panels below the distributions, the ratios of data to the background function are displayed. The shaded green areas represent the statistical uncertainty from the fit. The $\chi^2$ values per number of degrees of freedom ($\chi^2$/n.d.f.) and the corresponding $p$-values are provided for each fit.

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Measurements of inclusive and differential cross sections for top quark production in association with a Z boson in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Hayrapetyan, Aram ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
CMS-TOP-23-004, 2024.
Inspire Record 2844499 DOI 10.17182/hepdata.149880

Measurements are presented of inclusive and differential cross sections for Z boson associated production of top quark pairs ($\mathrm{t\bar{t}}$Z) and single top quarks (tZq or tWZ). The data were recorded in proton-proton collisions at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 138 fb$^{-1}$. Events with three or more leptons, electrons or muons, are selected and a multiclass deep neural network is used to separate three event categories, the $\mathrm{t\bar{t}}$Z and tWZ processes, the tZq process, and the backgrounds. A profile likelihood approach is used to unfold the differential cross sections, to account for systematic uncertainties, and to determine the correlations between the two signal categories in one global fit. The inclusive cross sections for a dilepton invariant mass between 70 and 110 GeV are measured to be 1.14 $\pm$ 0.07 pb for the sum of $\mathrm{t\bar{t}}$Z and tWZ, and 0.81 $\pm$ 0.10 pb for tZq, in good agreement with theoretical predictions.

25 data tables

Differential cross section of ttZ+tWZ as a function of the transverse momentum of the Z boson. The overflow is included in the last bin.

Differential cross section of tZq as a function of the transverse momentum of the Z boson. The overflow is included in the last bin.

Differential cross section of ttZ+tWZ as a function of the transverse momentum of the lepton coming from the W boson decay. The overflow is included in the last bin.

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Measurement of the inclusive $\mathrm{t\bar{t}}$ cross section in final states with at least one lepton and additional jets with 302 pb$^{-1}$ of pp collisions at $\sqrt{s}$ = 5.0 TeV

The CMS collaboration Hayrapetyan, Aram ; Tumasyan, Armen ; Adam, Wolfgang ; et al.
CMS-TOP-23-005, 2024.
Inspire Record 2844500 DOI 10.17182/hepdata.150676

A measurement of the top quark pair ($\mathrm{t\bar{t}}$) production cross section in proton-proton collisions at a centre-of-mass energy of 5.02 TeV is presented. The data were collected at the LHC in autumn 2017, in dedicated runs with low-energy and low-intensity conditions with respect to the default configuration, and correspond to an integrated luminosity of 302 pb$^{-1}$. The measurement is performed using events with one electron or muon, and multiple jets, at least one of them being identified as b quark (b tagged). Events are classified based on the number of all reconstructed jets and of b-tagged jets. Multivariate analysis techniques are used to enhance the separation between the signal and backgrounds. The measured cross section is 62.5 $\pm$ 1.6 (stat) $^{+2.6}_{-2.5}$ (syst) $\pm$ 1.2 (lumi) pb. A combination with the result in the dilepton channel based on the same data set yields a value of 62.3 $\pm$ 1.5 (stat) $\pm$ 2.4 (syst) $\pm$ 1.2 (lumi) pb, to be compared with the standard model prediction of 69.5$^{+3.5}_{-3.7}$ pb at next-to-next-to-leading order in perturbative quantum chromodynamics.

11 data tables

Distributions for data and expected signal and background contributions of the most discriminating input variables (\ensuremath{\Delta R_\mathrm{med}(\mathrm{j,j')}}) used for the random forest training, in the 3j1b category, before the maximum likelihood fit. The vertical error bars represent the statistical uncertainty in the data, and the shaded band the uncertainty in the prediction. All uncertainties considered in the analysis are included in the uncertainty band. The lower panels show the data-to-prediction ratio. The first and last bins in each distribution include underflow and overflow events, respectively.

Distributions for data and expected signal and background contributions of the most discriminating input variables (\ensuremath{\mathit{m}(\mathrm{u},\mathrm{u'})}) used for the random forest training, in the 3j1b category, before the maximum likelihood fit. The vertical error bars represent the statistical uncertainty in the data, and the shaded band the uncertainty in the prediction. All uncertainties considered in the analysis are included in the uncertainty band. The lower panels show the data-to-prediction ratio. The first and last bins in each distribution include underflow and overflow events, respectively.

Distributions for data and expected signal and background contributions of the MVA score for the e + jets channel in the 3j1b category, before the maximum likelihood fit. The vertical error bars represent the statistical uncertainty in the data, and the shaded band the uncertainty in the prediction. All uncertainties considered in the analysis are included in the uncertainty band. The lower panels show the data-to-prediction ratio. The first and last bins in each distribution include underflow and overflow events, respectively.

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