Search for heavy resonances and quantum black holes in e$\mu$, e$\tau$, and $\mu\tau$ final states in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
JHEP 05 (2023) 227, 2023.
Inspire Record 2081834 DOI 10.17182/hepdata.127302

A search is reported for heavy resonances and quantum black holes decaying into e$\mu$, e$\tau$, and $\mu\tau$ final states in proton-proton collision data recorded by the CMS experiment at the CERN LHC during 2016-2018 at $\sqrt{s}$ = 13 TeV, corresponding to an integrated luminosity of 138 fb$^{-1}$. The e$\mu$, e$\tau$, and $\mu\tau$ invariant mass spectra are reconstructed, and no evidence is found for physics beyond the standard model. Upper limits are set at 95% confidence level on the product of the cross section and branching fraction for lepton flavor violating signals. Three benchmark signals are studied: resonant $\tau$ sneutrino production in $R$ parity violating supersymmetric models, heavy Z' gauge bosons with lepton flavor violating decays, and nonresonant quantum black hole production in models with extra spatial dimensions. Resonant $\tau$ sneutrinos are excluded for masses up to 4.2 TeV in the e$\mu$ channel, 3.7 TeV in the e$\tau$ channel, and 3.6 TeV in the $\mu\tau$ channel. A Z' boson with lepton flavor violating couplings is excluded up to a mass of 5.0 TeV in the e$\mu$ channel, up to 4.3 TeV in the e$\tau$ channel, and up to 4.1 TeV in the $\mu\tau$ channel. Quantum black holes in the benchmark model are excluded up to the threshold mass of 5.6 TeV in the e$\mu$ channel, 5.2 TeV in the e$\tau$ channel, and 5.0 TeV in the $\mu\tau$ channel. In addition, model-independent limits are extracted to allow comparisons with other models for the same final states and similar event selection requirements. The results of these searches provide the most stringent limits available from collider experiments for heavy particles that undergo lepton flavor violating decays.

25 data tables

Mass distributions for the e$\mu$ channel. In addition to the observed data (black points) and SM prediction (filled histograms), expected signal distributions for three models are shown: the RPV SUSY model with $\lambda = \lambda' = 0.01$ and $\tau$ sneutrino mass of 1.6 TeV, a Z′ boson ($\mathcal{B}=0.1$) with a mass of 1.6 TeV , and the QBH signal expectation for $n=4$ and a threshold mass of 1.6 TeV. The bin width gradually increases with mass.

Mass distributions for the e$\tau$ channel. In addition to the observed data (black points) and SM prediction (filled histograms), expected signal distributions for three models are shown: the RPV SUSY model with $\lambda = \lambda' = 0.01$ and $\tau$ sneutrino mass of 1.6 TeV, a Z′ boson ($\mathcal{B}=0.1$) with a mass of 1.6 TeV , and the QBH signal expectation for $n=4$ and a threshold mass of 1.6 TeV. The bin width gradually increases with mass.

Mass distributions for the $\mu\tau$ channel. In addition to the observed data (black points) and SM prediction (filled histograms), expected signal distributions for three models are shown: the RPV SUSY model with $\lambda = \lambda' = 0.01$ and $\tau$ sneutrino mass of 1.6 TeV, a Z′ boson ($\mathcal{B}=0.1$) with a mass of 1.6 TeV , and the QBH signal expectation for $n=4$ and a threshold mass of 1.6 TeV. The bin width gradually increases with mass.

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Observation of electroweak W$^+$W$^-$ pair production in association with two jets in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
Phys.Lett.B 841 (2023) 137495, 2023.
Inspire Record 2080534 DOI 10.17182/hepdata.127763

An observation is reported of the electroweak production of a W$^+$W$^-$ pair in association with two jets, with both W bosons decaying leptonically. The data sample corresponds to an integrated luminosity of 138 fb$^{-1}$ of proton-proton collisions at $\sqrt{s}$ = 13 TeV, collected by the CMS detector at the CERN LHC. Events are selected by requiring exactly two opposite-sign leptons (electrons or muons) and two jets with large pseudorapidity separation and high dijet invariant mass. Events are categorized based on the flavor of the final-state leptons. A signal is observed with a significance of 5.6 standard deviations (5.2 expected) with respect to the background-only hypothesis. The measured fiducial cross section is 10.2 $\pm$ 2.0 fb and this value is consistent with the standard model prediction of 9.1 $\pm$ 0.6 fb.

1 data table

Measured and theoretical cross sections in the inclusive and exclusive fiducial volumes.


Search for Higgs boson decay to a charm quark-antiquark pair in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
Phys.Rev.Lett. 131 (2023) 061801, 2023.
Inspire Record 2080007 DOI 10.17182/hepdata.128675

A search for the standard model Higgs boson decaying to a charm quark-antiquark pair, H $\to$$\mathrm{c\bar{c}}$, produced in association with a leptonically decaying V (W or Z) boson is presented. The search is performed with proton-proton collisions at $\sqrt{s}$ = 13 TeV collected by the CMS experiment, corresponding to an integrated luminosity of 138 fb$^{-1}$. Novel charm jet identification and analysis methods using machine learning techniques are employed. The analysis is validated by searching for Z $\to$$\mathrm{c\bar{c}}$ in VZ events, leading to its first observation at a hadron collider with a significance of 5.7 standard deviations. The observed (expected) upper limit on $\sigma$(VH)$ \mathcal{B}$(H $\to$$\mathrm{c\bar{c}}$) is 0.94 (0.50 $^{+0.22}_{-0.15}$) pb at 95% confidence level (CL), corresponding to 14 (7.6 $^{+3.4}_{-2.3}$) times the standard model prediction. For the Higgs-charm Yukawa coupling modifier, $\kappa_\mathrm{c}$, the observed (expected) 95% CL interval is 1.1 $\lt$ $\vert\kappa_\mathrm{C}\vert$ $\lt$ 5.5 ($\vert\kappa_\mathrm{c}\vert$ $\lt$ 3.4), the most stringent constraint to date.

3 data tables

Signal strength modifier $\mu_{VZ(Z\to c \bar{c})}$, where V = W or Z.

Signal strength modifiers $\mu_{VH(H\to c \bar{c})}$, where V = W or Z.

Upper limits at 95% CL on the signal strength modifier $\mu_{VH(H\to c \bar{c})}$, per analysis channel and combined.


Measurement of the mass dependence of the transverse momentum of lepton pairs in Drell-Yan production in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
Eur.Phys.J.C 83 (2023) 628, 2023.
Inspire Record 2079374 DOI 10.17182/hepdata.115656

The double differential cross sections of the Drell-Yan lepton pair ($\ell^+\ell^-$, dielectron or dimuon) production are measured as functions of the invariant mass $m_{\ell\ell}$, transverse momentum $p_\mathrm{T}(\ell\ell)$, and $\phi^*_\eta$. The $\phi^*_\eta$ observable, derived from angular measurements of the leptons and highly correlated with $p_\mathrm{T}(\ell\ell)$, is used to probe the low-$p_\mathrm{T}(\ell\ell)$ region in a complementary way. Dilepton masses up to 1 TeV are investigated. Additionally, a measurement is performed requiring at least one jet in the final state. To benefit from partial cancellation of the systematic uncertainty, the ratios of the differential cross sections for various $m_{\ell\ell}$ ranges to those in the Z mass peak interval are presented. The collected data correspond to an integrated luminosity of 36.3 fb$^{-1}$ of proton-proton collisions recorded with the CMS detector at the LHC at a centre-of-mass energy of 13 TeV. Measurements are compared with predictions based on perturbative quantum chromodynamics, including soft-gluon resummation.

77 data tables

The measured differential cross section in the $50 \le M_{ll} < 76$ GeV mass window, in bins of the dilepton transverse momentum. The values are normalized by the bin width.

The measured differential cross section in the $50 \le M_{ll} < 76$ GeV mass window, in bins of the dilepton transverse momentum. The values are normalized by the bin width. This entry contains the covariance matrix of the results.

The measured differential cross section in the $76 \le M_{ll} < 106$ GeV mass window, in bins of the dilepton transverse momentum. The values are normalized by the bin width.

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Measurement of differential cross sections for the production of a Z boson in association with jets in proton-proton collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
Phys.Rev.D 108 (2023) 052004, 2023.
Inspire Record 2078067 DOI 10.17182/hepdata.115655

A measurement is presented of the production of Z bosons that decay into two electrons or muons in association with jets, in proton-proton collisions at a centre-of-mass energy of 13 TeV. The data were recorded by the CMS Collaboration at the LHC with an integrated luminosity of 35.9 fb$^{-1}$. The differential cross sections are measured as a function of the transverse momentum ($p_\mathrm{T}$) of the Z boson and the transverse momentum and rapidities of the five jets with largest $p_\mathrm{T}$. The jet multiplicity distribution is measured for up to eight jets. The hadronic activity in the events is estimated using the scalar sum of the $p_\mathrm{T}$ of all the jets. All measurements are unfolded to the stable particle-level and compared with predictions from various Monte Carlo event generators, as well as with expectations at leading and next-to-leading orders in perturbative quantum chromodynamics.

70 data tables

Measured cross section as a function of exclusive jet multiplicity, $N_{\text{jets}}$, and breakdown of the relative uncertainty.

Bin-to-bin correlation in the measured cross section as a function of exclusive jet multiplicity, $N_{\text{jets}}$.

Measured cross section as a function of the rapidity absolute value of the first jet, $|y(\text{j}_1)|$, and breakdown of the relative uncertainty.

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Search for CP violation using $\mathrm{t\bar{t}}$ events in the lepton+jets channel in pp collisions at $\sqrt{s}$ = 13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
JHEP 06 (2023) 081, 2023.
Inspire Record 2077553 DOI 10.17182/hepdata.114781

Results are presented on a search for CP violation in the production and decay of top quark-antiquark pairs in the lepton+jets channel. The search is based on data from proton-proton collisions at 13 TeV, collected with the CMS detector, corresponding to an integrated luminosity of 138 fb$^{-1}$. Possible CP violation effects are evaluated by measuring uncorrected asymmetries in observables constructed from linearly independent four-momentum vectors of the final-state particles. The dimensionless chromoelectric dipole moment of the top quark obtained from the observed asymmetries is measured to be 0.04 $\pm$ 0.10 (stat) $\pm$ 0.07 (syst), and the asymmetries exhibit no evidence for CP-violating effects, consistent with expectations from the standard model.

4 data tables

Results for the measurement of the effective asymmetries for each observable for the separate electron and muon channels, as well as for the combined lepton+jets channel.

Results for the measurement of the dimensionless CEDM for each observable and the combined lepton+jets channel.

Results for the measurement of the CP-violating asymmetries for each observable for the combined lepton+jets channel.

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Azimuthal correlations within exclusive dijets with large momentum transfer in photon-lead collisions

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Bergauer, Thomas ; et al.
Phys.Rev.Lett. 131 (2023) 051901, 2023.
Inspire Record 2075414 DOI 10.17182/hepdata.95235

The structure of nucleons is multidimensional and depends on the transverse momenta, spatial geometry, and polarization of the constituent partons. Such a structure can be studied using high-energy photons produced in ultraperipheral heavy-ion collisions. The first measurement of the azimuthal angular correlations of exclusively produced events with two jets in photon-lead interactions at large momentum transfer is presented, a process that is considered to be sensitive to the underlying nuclear gluon polarization. This study uses a data sample of ultraperipheral lead-lead collisions at $\sqrt{s_\mathrm{NN}}$ = 5.02 TeV, corresponding to an integrated luminosity of 0.38 nb$^{-1}$, collected with the CMS experiment at the LHC. The measured second harmonic of the correlation between the sum and difference of the two jet momenta is found to be positive, and rising, as the dijet momentum increases. A well-tuned model that has been successful at describing a wide range of proton scattering data from the HERA experiments fails to describe the observed correlations, suggesting the presence of gluon polarization effects.

2 data tables

The unfolded 1/${N_{\mathrm{events}}} dN/d\Phi$ distribution

The unfolded $<\cos(2\Phi)>$ distribution as a function of $Q_{\mathrm{T}}$


Strange hadron collectivity in pPb and PbPb collisions

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
JHEP 05 (2023) 007, 2023.
Inspire Record 2075415 DOI 10.17182/hepdata.115425

The collective behavior of K$^0_\mathrm{S}$ and $\Lambda/\bar{\Lambda}$ strange hadrons is studied by measuring the elliptic azimuthal anisotropy ($v_2$) using the scalar-product and multiparticle correlation methods. Proton-lead (pPb) collisions at a nucleon-nucleon center-of-mass energy $\sqrt{s_\mathrm{NN}}$ = 8.16 TeV and lead-lead (PbPb) collisions at $\sqrt{s_\mathrm{NN}}$ = 5.02 TeV collected by the CMS experiment at the LHC are investigated. Nonflow effects in the pPb collisions are studied by using a subevent cumulant analysis and by excluding events where a jet with transverse momentum greater than 20\GeV is present. The strange hadron $v_2$ values extracted in \pPb collisions via the four- and six-particle correlation method are found to be nearly identical, suggesting the collective behavior. Comparisons of the pPb and PbPb results for both strange hadrons and charged particles illustrate how event-by-event flow fluctuations depend on the system size.

55 data tables

The elliptic flow $v_2\{4\}$ for charged hadron as a function of $p_T$ in PbPb collision at 5.02 TeV.

The elliptic flow $v_2\{6\}$ for charged hadron as a function of $p_T$ in PbPb collision at 5.02 TeV.

The elliptic flow $v_2\{8\}$ for charged hadron as a function of $p_T$ in PbPb collision at 5.02 TeV.

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Search for light Higgs bosons from supersymmetric cascade decays in pp collisions at $\sqrt{s}$ =13 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Andrejkovic, Janik Walter ; et al.
Eur.Phys.J.C 83 (2023) 571, 2023.
Inspire Record 2074138 DOI 10.17182/hepdata.114359

A search is reported for pairs of light Higgs bosons (H$_1$) produced in supersymmetric cascade decays in final states with small missing transverse momentum. A data set of LHC pp collisions collected with the CMS detector at $\sqrt{s}$ = 13 TeV and corresponding to an integrated luminosity of 138 fb$^{-1}$ is used. The search targets events where both H$_1$ bosons decay into $\mathrm{b\bar{b}}$ pairs that are reconstructed as large-radius jets using substructure techniques. No evidence is found for an excess of events beyond the background expectations of the standard model (SM). Results from the search are interpreted in the next-to-minimal supersymmetric extension of the SM, where a "singlino" of small mass leads to squark and gluino cascade decays that can predominantly end in a highly Lorentz-boosted singlet-like H$_1$ and a singlino-like neutralino of small transverse momentum. Upper limits are set on the product of the squark or gluino pair production cross section and the square of the $\mathrm{b\bar{b}}$ branching fraction of the H$_1$ in a benchmark model containing almost mass-degenerate gluinos and light-flavour squarks. Under the assumption of an SM-like H$_1$$\to$$\mathrm{b\bar{b}}$ branching fraction, H$_1$ bosons with masses in the range 40-120 GeV arising from the decays of squarks or gluinos with a mass of 1200 to 2500 GeV are excluded at 95% confidence level.

9 data tables

Reference acceptance times efficiency values for the kinematic selection and $H_T>3500\;\mathrm{GeV}$ requirements ($A_{\mathrm{kin}}$) for the benchmark signal model with different values of $m_{\mathrm{SUSY}}$. These values are independent of $m_{\mathrm{H_1}}$ within 2% in the range $30 \le m_{\mathrm{H_1}} \le 125\;\mathrm{GeV}$.

Upper limits at 95% CL on $\sigma\times\mathcal{B}^2(\mathrm{H}_1\rightarrow b\bar{b}) \times A_{\mathrm{kin}}$ as a function of $m_{\mathrm{H_1}}$. The results are independent of $m_{\mathrm{SUSY}}$ within 10% in the range $1600<m_{\mathrm{SUSY}}<2800\;\mathrm{GeV}$.

Upper limits at 95% CL on $\sigma\times\mathcal{B}^2(\mathrm{H}_1\rightarrow b\bar{b})$ as a function of $m_{\mathrm{H_1}}$ for $m_{\mathrm{SUSY}}=1200\;\mathrm{GeV}$.

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Two-particle azimuthal correlations in $\gamma$p interactions using pPb collisions at $\sqrt{s_\mathrm{NN}}$ = 8.16 TeV

The CMS collaboration Tumasyan, Armen ; Adam, Wolfgang ; Bergauer, Thomas ; et al.
Phys.Lett.B 844 (2023) 137905, 2023.
Inspire Record 2074094 DOI 10.17182/hepdata.89877

The first measurements of the Fourier coefficients ($V_{n\Delta}$) of the azimuthal distributions of charged hadrons emitted from photon-proton ($\gamma$p) interactions at the LHC are presented. The data are extracted from 68.8 nb$^{-1}$ of ultra-peripheral proton-lead (pPb) collisions at $\sqrt{s_\mathrm{NN}}$ = 8.16 TeV using the CMS detector. The high energy lead ions produce a flux of photons that can interact with the oncoming proton. This $\gamma$p system provides a set of unique initial conditions with multiplicity lower than in photon-lead collisions but comparable to recent electron-positron and electron-proton data. The $V_{n\Delta}$ coefficients are presented in ranges of event multiplicity and transverse momentum ($p_\mathrm{T}$) and are compared to corresponding hadronic minimum bias pPb results. For a given multiplicity range, the mean $p_\mathrm{T}$ of charged particles is smaller in $\gamma$p than in pPb collisions. For both the $\gamma$p and pPb samples, $V_{1\Delta}$ is negative, $V_{2\Delta}$ is positive, and $V_{3\Delta}$ consistent with 0. For each multiplicity and $p_\mathrm{T}$ range, $V_{2\Delta}$ is larger for $\gamma$p events. The $\gamma$p data are consistent with model predictions that have no collective effects.

8 data tables

$V_{n\Delta}$ coefficients for $\gamma$p events as a function of N$_{\text{trk}}$ for $ 0.3 < p_\mathrm{T} < 3.0 GeV$ in pPb collisions at 8.16 TeV.

$V_{n\Delta}$ coefficients for minimum bias events as a function of N$_{\text{trk}}$ for $ 0.3 < p_\mathrm{T} < 3.0 GeV$ in pPb collisions at 8.16 TeV.

$V_{n\Delta}$ coefficients for $\gamma$p events as a function of N$_{\text{trk}}$ for $ 1.0 < p_\mathrm{T} < 3.0 GeV$ in pPb collisions at 8.16 TeV.

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