Browsing by Author "Makarenko, V."

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Citation - WoS: 1
Citation - Scopus: 4
Bottom Quark Energy Loss and Hadronization With B+ and Bs0 Nuclear Modification Factors Using pp and Pbpb Collisions at Snn = 5.02 TeV
(Springer Science and Business Media Deutschland GmbH, 2025) Hayrapetyan, A.; Tumasyan, A.; Adam, W.; Andrejkovic, J.W.; Bergauer, T.; Chatterjee, S.; Makarenko, V.
The production cross sections of Bs0 and B+ mesons are reported in proton-proton (pp) collisions recorded by the CMS experiment at the CERN LHC with a center-of-mass energy of 5.02 TeV. The data sample corresponds to an integrated luminosity of 302 pb−1. The cross sections are based on measurements of the Bs0→ J/ψ(μ+μ−)ϕ(1020)(K+K−) and B+→ J/ψ(μ+μ−)K+ decay channels. Results are presented in the transverse momentum (pT) range 7–50 GeV/c and the rapidity interval |y| < 2.4 for the B mesons. The measured pT-differential cross sections of B+ and Bs0 in pp collisions are well described by fixed-order plus next-to-leading logarithm perturbative quantum chromodynamics calculations. Using previous PbPb collision measurements at the same nucleon-nucleon center-of-mass energy, the nuclear modification factors, RAA, of the B mesons are determined. For pT> 10 GeV/c, both mesons are found to be suppressed in PbPb collisions (with RAA values significantly below unity), with less suppression observed for the Bs0 mesons. In this pT range, the RAA values for the B+ mesons are consistent with those for inclusive charged hadrons and D0 mesons. Below 10 GeV/c, both B+ and Bs0 are found to be less suppressed than either inclusive charged hadrons or D0 mesons, with the Bs0RAA value consistent with unity. The RAA values found for the B+ and Bs0 are compared to theoretical calculations, providing constraints on the mechanism of bottom quark energy loss and hadronization in the quark-gluon plasma, the hot and dense matter created in ultrarelativistic heavy ion collisions. © The Author(s) 2025.
Citation - Scopus: 2
Constraints on Standard Model Effective Field Theory for a Higgs Boson Produced in Association with W or Z Bosons in the H → B(b)over-Bar Decay Channel in Proton-Proton Collisions at √s=13 TeV
(Springer, 2025) Chekhovsky, V.; Hayrapetyan, A.; Makarenko, V.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Lee, J.
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.
Citation - WoS: 1
Determination of the Strong Coupling and Its Running from Measurements of Inclusive Jet Production
(Elsevier, 2025) Chekhovsky, V.; Hayrapetyan, A.; Makarenko, V.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Lee, J.
The value of the strong coupling alpha(S) is determined in a comprehensive analysis at next-to-next-to-leading order accuracy in quantum chromodynamics. The analysis uses double-differential cross section measurements from the CMS Collaboration at the CERN LHC of inclusive jet production in proton-proton collisions at centre-of-mass energies of 2.76, 7, 8, and 13 TeV, combined with inclusive deep-inelastic data from HERA. The value alpha(S)(m(Z)) = 0.1176(-0.0016)(+0.0014) is obtained at the scale of the Z boson mass. By using the measurements in different intervals of jet transverse momentum, the running of alpha(S) is probed for energies between 100 and 1600GeV.
Citation - WoS: 1
Citation - Scopus: 2
Energy-Scaling Behavior of Intrinsic Transverse-Momentum Parameters in Drell-Yan Simulation
(Amer Physical Soc, 2025) Hayrapetyan, A.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Bergauer, T.; Chatterjee, S.; Makarenko, V.
An analysis is presented based on models of the intrinsic transverse momentum (intrinsic k(T)) of partons in nucleons by studying the dilepton transverse momentum in Drell-Yan events. Using parameter tuning in event generators and existing data from fixed-target experiments and from hadron colliders, our investigation spans 3 orders of magnitude in center-of-mass energy and 2 orders of magnitude in dilepton invariant mass. The results show an energy-scaling behavior of the intrinsic k(T) parameters, independent of the dilepton invariant mass at a given center-of-mass energy.
Citation - Scopus: 2
Evidence for Similar Collectivity of High Transverse-Momentum Particles in P-Pb and Pb-Pb Collisions
(American Physical Society, 2025) Chekhovsky, V.; Hayrapetyan, A.; Makarenko, V.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Druzhkin, D.
Charged hadron elliptic anisotropies (v(2)) are presented over a wide transverse momentum (p(T)) range for proton-lead (pPb) and lead-lead (PbPb) collisions at nucleon-nucleon center-of-mass energies of 8.16 and 5.02 TeV, respectively. The data were recorded by the CMS experiment and correspond to integrated luminosities of 186 and 0.607 nb(-1) for the pPb and PbPb systems, respectively. A four-particle cumulant analysis is performed using subevents separated in pseudorapidity to effectively suppress noncollective effects. At high pT (p(T) > 8 GeV), significant positive v(2) values that are similar between pPb and PbPb collisions at comparable charged particle multiplicities are observed. This observation suggests a common origin for the multiparticle collectivity for high-p(T) particles in the two systems.
Identification of Low-Momentum Muons in the CMS Detector Using Multivariate Techniques in Proton-Proton Collisions at √s=13.6 TeV
(IOP Publishing Ltd, 2025) Chekhovsky, V.; Hayrapetyan, A.; Makarenko, V.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Kumar, A.
Soft muons with a transverse momentum below 10 GeV are featured in many processes studied by the CMS experiment, such as decays of heavy-flavor hadrons or rare tau lepton decays. Maximizing the selection efficiency for these muons, while simultaneously suppressing backgrounds from long-lived light-flavor hadron decays, is therefore important for the success of the CMS physics program. Multivariate techniques have been shown to deliver better muon identification performance than traditional selection techniques. To take full advantage of the large data set currently being collected during Run 3 of the CERN LHC, a new multivariate classifier based on a gradient-boosted decision tree has been developed. It offers a significantly improved separation of signal and background muons compared to a similar classifier used for the analysis of the Run 2 data. The performance of the new classifier is evaluated on a data set collected with the CMS detector in 2022 and 2023, corresponding to an integrated luminosity of 62 fb(-1).
Citation - Scopus: 2
Measurement of Boosted Higgs Bosons Produced Via Vector Boson Fusion or Gluon Fusion in the H → B(b)over-Bar Decay Mode Using Lhc Proton-Proton Collision Data at √s=13 Tev
(Springer, 2024) Hayrapetyan, A.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Bergauer, T.; Chatterjee, S.; Makarenko, V.
A measurement is performed of Higgs bosons produced with high transverse momentum (p(T)) via vector boson or gluon fusion in proton-proton collisions. The result is based on a data set with a center-of-mass energy of 13 TeV collected in 2016-2018 with the CMS detector at the LHC and corresponds to an integrated luminosity of 138 fb(-1). The decay of a high-p(T) Higgs boson to a boosted bottom quark-antiquark pair is selected using large-radius jets and employing jet substructure and heavy-flavor taggers based on machine learning techniques. Independent regions targeting the vector boson and gluon fusion mechanisms are defined based on the topology of two quark-initiated jets with large pseudorapidity separation. The signal strengths for both processes are extracted simultaneously by performing a maximum likelihood fit to data in the large-radius jet mass distribution. The observed signal strengths relative to the standard model expectation are 4.9(-1.6)(+1.9) and 1.6(-1.5)(+1.7) for the vector boson and gluon fusion mechanisms, respectively. A differential cross section measurement is also reported in the simplified template cross section framework.
Citation - Scopus: 2
Measurement of Light-By Scattering and the Breit-Wheeler Process, and Search for Axion-Like Particles in Ultraperipheral PbPb Collisions at √snn=5.02 TeV
(Springer, 2025) Hayrapetyan, A.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Bergauer, T.; Chatterjee, S.; Makarenko, V.
Measurements of light-by-light scattering (LbL, gamma gamma -> gamma gamma) and the Breit-Wheeler process (BW, gamma gamma -> e(+)e(-)) are reported in ultraperipheral PbPb collisions at a centre-of-mass energy per nucleon pair of 5.02 TeV. The data sample, corresponding to an integrated luminosity of 1.7 nb(-1), was collected by the CMS experiment at the CERN LHC in 2018. Events with an exclusively produced gamma gamma or e(+)e(-) pair with invariant masses m(gamma gamma,ee) > 5 GeV, along with other fiducial criteria, are selected. The measured BW fiducial production cross section, sigma(fid)(gamma gamma -> e(+)e(-)) = 263.5 +/- 1.8(stat) +/- 17.8(syst) mu b, as well as the differential distributions for various kinematic observables, are in agreement with leading-order quantum electrodynamics predictions complemented with final-state photon radiation. The measured differential BW cross sections allow discrimination between different theoretical descriptions of the photon flux of the lead ion. In the LbL final state, 26 exclusive diphoton candidate events are observed compared with 12.0 +/- 2.9 expected for the background. Combined with previous results, the observed significance of the LbL signal with respect to the background-only hypothesis is above five standard deviations. The measured fiducial LbL scattering cross section, sigma(fid)(gamma gamma -> gamma gamma) = 107 +/- 24(stat) +/- 13(syst) nb, is in agreement with next- to-leading-order predictions. Limits on the production of axion-like particles coupled to photons are set over the mass range 5-100 GeV, including the most stringent limits to date in the range of 5-10 GeV.
Citation - WoS: 2
Citation - Scopus: 3
Measurement of the Higgs Boson Mass and Width Using the Four-Lepton Final State in Proton-Proton Collisions at (Formula Presented)
(American Physical Society, 2025) Hayrapetyan, A.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Bergauer, T.; Chatterjee, S.; Makarenko, V.
A measurement of the Higgs boson mass and width via its decay to two Z bosons is presented. Proton-proton collision data collected by the CMS experiment, corresponding to an integrated luminosity of 138 fb(-1) at a center-of-mass energy of 13 TeV, is used. The invariant mass distribution of four leptons in the on-shell Higgs boson decay is used to measure its mass and constrain its width. This yields the most precise single measurement of the Higgs boson mass to date, 125.04 +/- 0.12 GeV, and an upper limit on the width Gamma(H) < 330 MeV at 95% confidence level. A combination of the on- and off-shell Higgs boson production decaying to four leptons is used to determine the Higgs boson width, assuming that no new virtual particles affect the production, a premise that is tested by adding new heavy particles in the gluon fusion loop model. This result is combined with a previous CMS analysis of the off-shell Higgs boson production with decay to two leptons and two neutrinos, giving a measured Higgs boson width of 3.0(-1.5)(+2.0) MeV, in agreement with the standard model prediction of 4.1 MeV. The strength of the off-shell Higgs boson production is also reported. The scenario of no off-shell Higgs boson production is excluded at a confidence level corresponding to 3.8 standard deviations.
Measurement of Wwz and Zh Production Cross Sections at √s=13 and 13.6 TeV
(American Physical Society, 2025) Hayrapetyan, A.; Makarenko, V.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Benato, L.; Choi, J.
A measurement is presented of the cross section in proton-proton collisions for the production of two W bosons and one Z boson. It is based on data recorded by the CMS experiment at the CERN LHC at center-of-mass energies root s = 13 and 13.6 TeV, corresponding to an integrated luminosity of 200 fb(-1). Events with four charged leptons (electrons or muons) in the final state are selected. Both nonresonant WWZ production and ZH production, with the Higgs boson decaying into two W bosons, are reported. For the first time, the two processes are measured separately in a simultaneous fit. Combining the two modes, signal strengths relative to the standard model (SM) predictions of 0.75(-0.29)(+0.34) and 1.74(-0.60)(+0.71) are measured for root s = 13 and 13.6 TeV, respectively. The observed (expected) significance for the triboson signal is 3.8 (2.5) standard deviations for root s = 13.6 TeV, thus providing the first evidence for triboson production at this center-of-mass energy. Combining the two modes and the two center-of-mass energies, the inclusive signal strength relative to the SM prediction is measured to be 1.03(-0.28)(+0.31), with an observed (expected) significance of 4.5 (5.0) standard deviations.
Citation - WoS: 1
Citation - Scopus: 2
Measurements of Inclusive and Differential Cross Sections for Top Quark Production in Association With a Z Boson in Proton-Proton Collisions at √s=13 TeV
(Springer, 2025) Hayrapetyan, A.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Bergauer, T.; Chatterjee, S.; Makarenko, V.
Measurements are presented of inclusive and differential cross sections for Z boson associated production of top quark pairs (t (t) over barZ) 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 t (t) over barZ 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 +/- 0.07 pb for the sum of t (t) over barZ and tWZ, and 0.81 +/- 0.10 pb for tZq, in good agreement with theoretical predictions.
Citation - Scopus: 1
Measurements of Inclusive and Differential Higgs Boson Production Cross Sections at √s=13.6 TeV in the H → Γγ Decay Channel
(Springer, 2025) Hayrapetyan, A.; Makarenko, V.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Benato, L.; Sosnov, D.
Inclusive and differential cross sections for Higgs boson production in proton-proton collisions at a centre-of-mass energy of 13.6TeV are measured using data collected with the CMS detector at the LHC in 2022, corresponding to an integrated luminosity of 34.7 fb(-1). Events with the diphoton final state are selected, and the measured inclusive fiducial cross section is sfid = 74 +/- 11 (stat)(-4)(+5) (syst) fb, in agreement with the standard model prediction of 67.8 +/- 3.8 fb. Differential cross sections are measured as functions of several observables: the Higgs boson transverse momentum and rapidity, the number of associated jets, and the transverse momentum of the leading jet in the event. Within the uncertainties, the differential cross sections agree with the standard model predictions.
Citation - Scopus: 1
Measurements of the Higgs Boson Production Cross Section in the Four-Lepton Final State in Proton-Proton Collisions at = 13.6 TeV
(Springer Science and Business Media Deutschland GmbH, 2025) Tchekhovski, V.; Hayrapetyan, A.; Makarenko, V.; Tumasyan, A.; Adam, W.; Andrejkovic, J.W.; Druzhkin, D.
The measurements of the Higgs boson (H) production cross sections performed by the CMS Collaboration in the four-lepton (4ℓ, ℓ = e, μ) final state at a center-of-mass energy = 13.6 TeV are presented. These measurements are based on data collected with the CMS detector at the CERN LHC in 2022, corresponding to an integrated luminosity of 34.7 fb−1. Cross sections are measured in a fiducial region closely matching the experimental acceptance, both inclusively and differentially, as a function of the transverse momentum and the absolute value of the rapidity of the four-lepton system. The H → ZZ → 4ℓ inclusive fiducial cross section is measured to be fb, in agreement with the standard model expectation of fb. © The Author(s) 2025.
A Method for Correcting the Substructure of Multiprong Jets using the Lund Jet Plane
(Springer Science and Business Media Deutschland GmbH, 2025) Hayrapetyan, A.; Makarenko, V.; Tumasyan, A.; Adam, W.; Andrejkovic, J.W.; Benato, L.; Sosnov, D.
Many analyses at the CERN LHC exploit the substructure of jets to identify heavy resonances produced with high momenta that decay into multiple quarks and/or gluons. This paper presents a new technique for correcting the substructure of simulated large-radius jets from multiprong decays. The technique is based on reclustering the jet constituents into several subjets such that each subjet represents a single prong, and separately correcting the radiation pattern in the Lund jet plane of each subjet using a correction derived from data. The data presented here correspond to an integrated luminosity of 138 fb−1 collected by the CMS experiment between 2016–2018 at a center-of-mass energy of 13 TeV. The correction procedure improves the agreement between data and simulation for several different substructure observables of multiprong jets. This technique establishes, for the first time, a robust calibration for the substructure of jets with four or more prongs, enabling future measurements and searches for new phenomena containing these signatures. © The Author(s) 2025.
Citation - WoS: 9
Model-Agnostic Search for Dijet Resonances with Anomalous Jet Substructure in Proton-Proton Collisions at S=13 TeV
(IOP Publishing Ltd, 2025) Chekhovsky, V.; Hayrapetyan, A.; Makarenko, V.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Kaur, A.
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.
Observation of Coherent (Formula Presented) Meson Photoproduction in Ultraperipheral PbPb Collisions at (Formula Presented)
(American Physical Society, 2025) Tchekhovski, V.; Hayrapetyan, A.; Makarenko, V.; Tumasyan, A.; Adam, W.; Andrejkovic, J.W.; Druzhkin, D.
The first observation of coherent (Formula presented) meson photoproduction off heavy nuclei is presented using ultraperipheral lead-lead collisions at a center-of-mass energy per nucleon pair of 5.36 TeV. The data were collected by the CMS experiment and correspond to an integrated luminosity of (Formula presented). The (Formula presented) meson signals are reconstructed via the (Formula presented) decay channel. The production cross section is presented as a function of the (Formula presented) meson rapidity in the range (Formula presented), probing gluons that carry a fraction of the nucleon momentum ((Formula presented)) around (Formula presented). The observed cross section exhibits little dependence on rapidity and is significantly suppressed, by a factor of (Formula presented), compared to a baseline model that treats a nucleus as a collection of free nucleons. Theoretical models that incorporate the nuclear shadowing effect generally provide a better description of the (Formula presented) data than those incorporating gluon saturation. This study establishes a powerful new tool for exploring nuclear effects and nuclear gluonic structure in the small-(Formula presented) regime at a unique energy scale bridging the perturbative and nonperturbative quantum chromodynamics domains. © 2025 CERN, for the CMS Collaboration.
Citation - WoS: 3
Citation - Scopus: 4
Observation of Double j Meson Production in ppb Collisions at √s_{nn< Tev}
(Amer Physical Soc, 2024) Hayrapetyan, A.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Bergauer, T.; Chatterjee, S.; Makarenko, V.
The first observation of the concurrent production of two J/psi mesons in proton-nucleus collisions is presented. The analysis is based on a proton-lead (pPb) data sample recorded at a nucleon-nucleon center-of-mass energy of 8.16 TeV by the CMS experiment at the CERN LHC and corresponding to an integrated luminosity of 174.6 nb(-1). The two J/psi mesons are reconstructed in their mu(+)mu(-) decay channels with transverse momenta p(T) > 6.5 GeV and rapidity vertical bar y vertical bar < 2.4. Events where one of the J/psi mesons is reconstructed in the dielectron channel are also considered in the search. The pPb -> J/psi J/psi +X process is observed with a significance of 5.3 standard deviations. The measured inclusive fiducial cross section, using the four-muon channel alone, is sigma(pPb (-> J/psi J/psi + X) = 22.0 +/- 8.9(stat) +/- 1.5(syst) nb. A fit of the data to the expected rapidity separation for pairs of J/psi mesons produced in single (SPS) and double (DPS) parton scatterings yields sigma(pPb)(SPS) (-> J/psi J/psi + X) = 16.5 +/- 10.8(stat) +/- 0.1(syst) nb and sigma(pPb)(DPS) (-> J/psi J/psi + X) = 5.4 +/- 6.2(stat) +/- 0.4(syst) nb, respectively. This latter result can he transformed into a lower hound on the effective DPS cross section, closely related to the squared average interparton transverse separation in the collision, of sigma(eff) > 1.0 mb at 95% confidence level.
Observation of Nuclear Modification of Energy-Energy Correlators Inside Jets in Heavy Ion Collisions
(Elsevier, 2025) Chekhovsky, V.; Hayrapetyan, A.; Makarenko, V.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Dutta, S.
Energy-energy correlators are constructed by averaging the number of charged particle pairs within jets, weighted by the product of their transverse momenta, as a function of the angular separation of the particles within a pair. They are sensitive to a multitude of perturbative and nonperturbative quantum chromodynamics phenomena in high-energy particle collisions. Using lead-lead data recorded with the CMS detector, energy-energy correlators inside high transverse momentum jets are measured in heavy ion collisions for the first time. The data are obtained at a nucleon-nucleon center-of-mass energy of 5.02TeV and correspond to an integrated luminosity of 1.70 nb(-1). A similar analysis is done for proton-proton collisions at the same center-of-mass energy to establish a reference. The ratio of lead-lead to proton-proton energy-energy correlators reveals significant jet substructure modifications in the quark-gluon plasma. The results are compared to different models that incorporate either color coherence or medium response effects, where the two effects predict similar substructure modifications.
Observation of the Charged-Particle Multiplicity Dependence of Σψ(2s)/Σj in P-Pb Collisions at 8.16 TeV
(American Physical Society, 2025) Chekhovsky, V.; Hayrapetyan, A.; Makarenko, V.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Dutta, S.
Bound states of charm and anticharm quarks, known as charmonia, have a rich spectroscopic structure that can be used to probe the dynamics of hadron production in high-energy hadron collisions. Here, the cross section ratio of excited (psi(2S)) and ground state (J/psi) vector mesons is measured as a function of the charged-particle multiplicity in proton-lead (pPb) collisions at a center-of-mass (CM) energy per nucleon pair of 8.16 TeV. The data corresponding to an integrated luminosity of 175 nb(-1) were collected using the CMS detector. The ratio is measured separately for prompt and nonprompt charmonia in the transverse momentum range 6.5 < p(T) < 30 GeV and in four rapidity ranges spanning -2.865 < y(CM) < 1.935. For the first time, a statistically significant multiplicity dependence of the prompt cross section ratio is observed in proton-nucleus collisions. There is no clear rapidity dependence in the ratio. The prompt measurements are compared with a theoretical model which includes interactions with nearby particles during the evolution of the system. These results provide additional constraints on hadronization models of heavy quarks in nuclear collisions.
Citation - WoS: 1
Observation of Wzγ Production and Constraints on New Physics Scenarios in Proton-Proton Collisions at √s=13 TeV
(American Physical Society, 2025) Chekhovsky, V.; Hayrapetyan, A.; Makarenko, V.; Tumasyan, A.; Adam, W.; Andrejkovic, J. W.; Druzhkin, D.
A measurement of the WZ gamma triboson production cross section is presented. The analysis is based on a data sample of proton-proton collisions at a center-of-mass energy of root s = 13 TeV recorded with the CMS detector at the LHC, corresponding to an integrated luminosity of 138 fb(-1). The analysis focuses on the final state with three charged leptons, l(+/-)nu l(+)l(-), where l = e or mu, accompanied by an additional photon. The observed (expected) significance of the WZ gamma signal is 5.4 (3.8) standard deviations. The cross section is measured in a fiducial region, where events with an l originating from a tau lepton decay are excluded, to be 5.48 +/- 1.11 fb, which is compatible with the prediction of 3.69 +/- 0.24 fb at next-to-leading order in quantum chromodynamics. Exclusion limits are set on anomalous quartic gauge couplings and on the production cross sections of massive axionlike particles.