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Article Citation - WoS: 86Citation - Scopus: 8Measurement of Single-Diffractive Dijet Production in Proton–proton Collisions at √s=8te With the Cms and Totem Experiments(Springer Nature, 2020) Sirunyan, A.M.; Karapınar, Güler; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; Josa, M.I.Measurements are presented of the single-diffractive dijet cross section and the diffractive cross section as a function of the proton fractional momentum loss ξ and the four-momentum transfer squared t. Both processes pp→pX and pp→Xp, i.e. with the proton scattering to either side of the interaction point, are measured, where X includes at least two jets; the results of the two processes are averaged. The analyses are based on data collected simultaneously with the CMS and TOTEM detectors at the LHC in proton–proton collisions at s=8Te during a dedicated run with β∗=90m at low instantaneous luminosity and correspond to an integrated luminosity of 37.5nb-1. The single-diffractive dijet cross section σjjpX, in the kinematic region ξ< 0.1 , 0.03<|t|<1Ge2, with at least two jets with transverse momentum pT>40Ge, and pseudorapidity | η| < 4.4 , is 21.7±0.9(stat)-3.3+3.0(syst)±0.9(lumi)nb. The ratio of the single-diffractive to inclusive dijet yields, normalised per unit of ξ, is presented as a function of x, the longitudinal momentum fraction of the proton carried by the struck parton. The ratio in the kinematic region defined above, for x values in the range - 2.9 ≤ log 10x≤ - 1.6 , is R=(σjjpX/Δξ)/σjj=0.025±0.001(stat)±0.003(syst), where σjjpX and σjj are the single-diffractive and inclusive dijet cross sections, respectively. The results are compared with predictions from models of diffractive and nondiffractive interactions. Monte Carlo predictions based on the HERA diffractive parton distribution functions agree well with the data when corrected for the effect of soft rescattering between the spectator partons. © 2020, CERN for the benefit of the CMS and TOTEM collaborations.Article Citation - WoS: 6Citation - Scopus: 7Correlations of Azimuthal Anisotropy Fourier Harmonics With Subevent Cumulants in Ppb Collisions at Snn =8.16 Tev(American Physical Society, 2021) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; Devetak, D.Event-by-event long-range correlations of azimuthal anisotropy Fourier coefficients (vn) in 8.16 TeV pPb data, collected by the CMS experiment at the CERN Large Hadron Collider, are extracted using a subevent four-particle cumulant technique applied to very low multiplicity events. Each combination of four charged particles is selected from either two, three, or four distinct subevent regions of a pseudorapidity range from -2.4 to 2.4 of the CMS tracker, and with transverse momentum between 0.3 and 3.0 GeV. Using the subevent cumulant technique, correlations between vn of different orders are measured as functions of particle multiplicity and compared to the standard cumulant method without subevents over a wide event multiplicity range. At high multiplicities, the v2 and v3 coefficients exhibit an anticorrelation; this behavior is observed consistently using various methods. The v2 and v4 correlation strength is found to depend on the number of subevents used in the calculation. As the event multiplicity decreases, the results from different subevent methods diverge because of different contributions of noncollective or few-particle correlations. Correlations extracted with the four-subevent method exhibit a tendency to diminish monotonically toward the lowest multiplicity region (about 20 charged tracks) investigated. These findings extend previous studies to a significantly lower event multiplicity range and establish the evidence for the onset of long-range collective multiparticle correlations in small system collisions. © 2021 CERN.Article Citation - WoS: 107Citation - Scopus: 153Evidence for Higgs Boson Decay To a Pair of Muons(Springer, 2021) Karapınar, Güler; CMS Collaboration; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; Salama, E.Evidence for Higgs boson decay to a pair of muons is presented. This result combines searches in four exclusive categories targeting the production of the Higgs boson via gluon fusion, via vector boson fusion, in association with a vector boson, and in association with a top quark-antiquark pair. The analysis is performed using proton-proton collision data at root s = 13 TeV, corresponding to an integrated luminosity of 137 fb(-1), recorded by the CMS experiment at the CERN LHC. An excess of events over the back- ground expectation is observed in data with a significance of 3.0 standard deviations, where the expectation for the standard model (SM) Higgs boson with mass of 125.38 GeV is 2.5. The combination of this result with that from data recorded at root s = 7 and 8 TeV, corresponding to integrated luminosities of 5.1 and 19.7 fb(-1), respectively, increases both the expected and observed significances by 1%. The measured signal strength, relative to the SM prediction, is 1.19(-0.39)(+0.40)(stat)(-0.14)(+0.15). This result constitutes the first evidence for the decay of the Higgs boson to second generation fermions and is the most precise measurement of the Higgs boson coupling to muons reported to date.Article Citation - WoS: 1Citation - Scopus: 6Search for Supersymmetry With Photons in Pp Collisions at S =8tev(American Physical Society, 2015) Khachatryan, V.; Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Calvo, E.Two searches for physics beyond the standard model in events containing photons are presented. The data sample used corresponds to an integrated luminosity of 19.7fb-1 of proton-proton collisions at s=8TeV, collected with the CMS experiment at the CERN LHC. The analyses pursue different inclusive search strategies. One analysis requires at least one photon, at least two jets, and a large amount of transverse momentum imbalance, while the other selects events with at least two photons and at least one jet, and uses the razor variables to search for signal events. The background expected from standard model processes is evaluated mainly from data. The results are interpreted in the context of general gauge-mediated supersymmetry, with the next-to-lightest supersymmetric particle either a bino- or wino-like neutralino, and within simplified model scenarios. Upper limits at the 95% confidence level are obtained for cross sections as functions of the masses of the intermediate supersymmetric particles. © 2015 CERN. © 2015 CERN, for the CMS Collaboration. Published by the American Physical Society under the terms of the "http://creativecommons.org/licenses/by/3.0/" Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.Article Citation - WoS: 48Citation - Scopus: 69Limits on the Higgs Boson Lifetime and Width From Its Decay To Four Charged Leptons(American Physical Society, 2015) Khachatryan, V.; Khachatryan, V.; Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Asilar, E.; Soares, M.S.Constraints on the lifetime and width of the Higgs boson are obtained from H→ZZ→4ℓ events using data recorded by the CMS experiment during the LHC run 1 with an integrated luminosity of 5.1 and 19.7fb-1 at a center-of-mass energy of 7 and 8 TeV, respectively. The measurement of the Higgs boson lifetime is derived from its flight distance in the CMS detector with an upper bound of τH<1.9×10-13s at the 95% confidence level (C.L.), corresponding to a lower bound on the width of ΓH>3.5×10-9MeV. The measurement of the width is obtained from an off-shell production technique, generalized to include anomalous couplings of the Higgs boson to two electroweak bosons. From this measurement, a joint constraint is set on the Higgs boson width and a parameter fΛQ that expresses an anomalous coupling contribution as an on-shell cross-section fraction. The limit on the Higgs boson width is ΓH<46MeV with fΛQ unconstrained and ΓH<26MeV for fΛQ=0 at the 95% C.L. The constraint fΛQ<3.8×10-3 at the 95% C.L. is obtained for the expected standard model Higgs boson width. © 2015 CERN, for the CMS. Published by the American Physical Society.Article Citation - WoS: 17Citation - Scopus: 19Measurement of Electroweak Production of a W Boson in Association With Two Jets in Proton–proton Collisions at √s=13te(Springer Nature, 2020) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; Gonzalez Lopez, O.A measurement is presented of electroweak (EW) production of a W boson in association with two jets in proton–proton collisions at s=13Te. The data sample was recorded by the CMS Collaboration at the LHC and corresponds to an integrated luminosity of 35.9fb-1. The measurement is performed for the ℓνjj final state (with ℓν indicating a lepton–neutrino pair, and j representing the quarks produced in the hard interaction) in a kinematic region defined by invariant mass mjj>120Ge and transverse momenta pTj>25Ge. The cross section of the process is measured in the electron and muon channels yielding σEW(Wjj)=6.23±0.12(stat)±0.61(syst)pb per channel, in agreement with leading-order standard model predictions. The additional hadronic activity of events in a signal-enriched region is studied, and the measurements are compared with predictions. The final state is also used to perform a search for anomalous trilinear gauge couplings. Limits on anomalous trilinear gauge couplings associated with dimension-six operators are given in the framework of an effective field theory. The corresponding 95% confidence level intervals are -2.3<cWWW/Λ2<2.5Te-2, -8.8<cW/Λ2<16Te-2, and -45<cB/Λ2<46Te-2. These results are combined with the CMS EW Zjj analysis, yielding the constraint on the cW W W coupling: -1.8<cWWW/Λ2<2.0Te-2. © 2020, CERN for the benefit of the CMS collaboration.Article Citation - WoS: 77Citation - Scopus: 90Measurement of T T ¯ Normalised Multi-Differential Cross Sections in Pp Collisions at √s=13tev , and Simultaneous Determination of the Strong Coupling Strength, Top Quark Pole Mass, and Parton Distribution Functions(Springer Nature, 2020) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; Goy Lopez, S.Normalised multi-differential cross sections for top quark pair (t t ¯) production are measured in proton-proton collisions at a centre-of-mass energy of 13TeV using events containing two oppositely charged leptons. The analysed data were recorded with the CMS detector in 2016 and correspond to an integrated luminosity of 35.9fb-1. The double-differential t t ¯ cross section is measured as a function of the kinematic properties of the top quark and of the t t ¯ system at parton level in the full phase space. A triple-differential measurement is performed as a function of the invariant mass and rapidity of the t t ¯ system and the multiplicity of additional jets at particle level. The data are compared to predictions of Monte Carlo event generators that complement next-to-leading-order (NLO) quantum chromodynamics (QCD) calculations with parton showers. Together with a fixed-order NLO QCD calculation, the triple-differential measurement is used to extract values of the strong coupling strength αS and the top quark pole mass (mtpole) using several sets of parton distribution functions (PDFs). The measurement of mtpole exploits the sensitivity of the t t ¯ invariant mass distribution to mtpole near the production threshold. Furthermore, a simultaneous fit of the PDFs, αS, and mtpole is performed at NLO, demonstrating that the new data have significant impact on the gluon PDF, and at the same time allow an accurate determination of αS and mtpole. The values αS(mZ)=0.1135-0.0017+0.0021 and mtpole=170.5±0.8GeV are extracted, which account for experimental and theoretical uncertainties, the latter being estimated from NLO scale variations. Possible effects from Coulomb and soft-gluon resummation near the t t ¯ production threshold are neglected in these parameter extractions. A rough estimate of these effects indicates an expected correction of mtpole of the order of +1GeV, which can be regarded as additional theoretical uncertainty in the current mtpole extraction. © 2020, CERN for the benefit of the CMS collaboration.Article Citation - WoS: 15Citation - Scopus: 16Studies of Charm Quark Diffusion Inside Jets Using Pb-Pb and Pp Collisions at Snn =5.02 Tev(American Physical Society, 2020) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; Devetak, D.The first study of charm quark diffusion with respect to the jet axis in heavy ion collisions is presented. The measurement is performed using jets with pTjet>60 GeV/c and D0 mesons with pTD>4 GeV/c in lead-lead (Pb-Pb) and proton-proton (pp) collisions at a nucleon-nucleon center-of-mass energy of sNN=5.02 TeV, recorded by the CMS detector at the LHC. The radial distribution of D0 mesons with respect to the jet axis is sensitive to the production mechanisms of the meson, as well as to the energy loss and diffusion processes undergone by its parent parton inside the strongly interacting medium produced in Pb-Pb collisions. When compared to Monte Carlo event generators, the radial distribution in pp collisions is found to be well described by pythia, while the slope of the distribution predicted by sherpa is steeper than that of the data. In Pb-Pb collisions, compared to the pp results, the D0 meson distribution for 4<pTD<20 GeV/c hints at a larger distance on average with respect to the jet axis, reflecting a diffusion of charm quarks in the medium created in heavy ion collisions. At higher pTD, the Pb-Pb and pp radial distributions are found to be similar. © 2020 CERN.Erratum Citation - WoS: 15Citation - Scopus: 7Erratum To: Measurements of the Z→4ℓ Branching Fraction, and Constraints on Anomalous Triple Gauge Couplings at S=13tev (the European Physical Journal C, (2018), 78, 2, (165), 10.1140/Epjc(Springer Nature, 2018) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; Virto, A.L.Reference [6]: “Phys. Lett. B 763, 280” should have been corrected into “Phys. Lett. B 763, 280 (2016)”. © 2018, CERN for the benefit of the CMS collaboration.Article Citation - WoS: 65Citation - Scopus: 69Search for New Physics in Same-Sign Dilepton Events in Proton–proton Collisions at √s = 13 Tev(Springer Nature, 2016) Khachatryan, V.; Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Scodellaro, L.A search for new physics is performed using events with two isolated same-sign leptons, two or more jets, and missing transverse momentum. The results are based on a sample of proton–proton collisions at a center-of-mass energy of 13TeV recorded with the CMS detector at the LHC, corresponding to an integrated luminosity of 2.3 fb1. Multiple search regions are defined by classifying events in terms of missing transverse momentum, the scalar sum of jet transverse momenta, the transverse mass associated with a W boson candidate, the number of jets, the number of b quark jets, and the transverse momenta of the leptons in the event. The analysis is sensitive to a wide variety of possible signals beyond the standard model. No excess above the standard model background expectation is observed. Constraints are set on various supersymmetric models, with gluinos and bottom squarks excluded for masses up to 1300 and 680GeV, respectively, at the 95 % confidence level. Upper limits on the cross sections for the production of two top quark-antiquark pairs (119fb) and two same-sign top quarks (1.7pb) are also obtained. Selection efficiencies and model independent limits are provided to allow further interpretations of the results. © 2016, CERN for the benefit of the CMS collaboration.