WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7150
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Article Citation - WoS: 29Citation - Scopus: 33Measurement of the Jet Mass in Highly Boosted T T ¯ Events From Pp Collisions at √s=8tev(Springer Nature, 2017) Sirunyan, A.M.; Karapınar, Güler; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; Baillon, P.The first measurement of the jet mass mjet of top quark jets produced in t t ¯ events from pp collisions at s=8TeV is reported for the jet with the largest transverse momentum pT in highly boosted hadronic top quark decays. The data sample, collected with the CMS detector, corresponds to an integrated luminosity of 19.7fb-1. The measurement is performed in the lepton+jets channel in which the products of the semileptonic decay t → b W with W → ℓν where ℓ is an electron or muon, are used to select t t ¯ events with large Lorentz boosts. The products of the fully hadronic decay t → b W with W → q q ¯ ′ are reconstructed using a single Cambridge–Aachen jet with distance parameter R= 1.2 , and pT> 400 GeV. The t t ¯ cross section as a function of mjet is unfolded at the particle level and is used to test the modelling of highly boosted top quark production. The peak position of the mjet distribution is sensitive to the top quark mass mt, and the data are used to extract a value of mt to assess this sensitivity. © 2017, CERN for the benefit of the CMS collaboration.Article Citation - WoS: 33Citation - Scopus: 45Measurement of the Triple-Differential Dijet Cross Section in Proton-Proton Collisions at √s=8tev and Constraints on Parton Distribution Functions(Springer Nature, 2017) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; Barney, D.A measurement is presented of the triple-differential dijet cross section at a centre-of-mass energy of 8TeV using 19.7fb-1 of data collected with the CMS detector in proton-proton collisions at the LHC. The cross section is measured as a function of the average transverse momentum, half the rapidity separation, and the boost of the two leading jets in the event. The cross section is corrected for detector effects and compared to calculations in perturbative quantum chromodynamics at next-to-leading order accuracy, complemented with electroweak and nonperturbative corrections. New constraints on parton distribution functions are obtained and the inferred value of the strong coupling constant is αS(MZ)=0.1199±0.0015(exp)-0.0020+0.0031(theo), where MZ is the mass of the Z boson. © 2017, CERN for the benefit of the CMS collaboration.Article Citation - WoS: 37Citation - Scopus: 43Search for Heavy Resonances That Decay Into a Vector Boson and a Higgs Boson in Hadronic Final States at √s=13tev(Springer Nature, 2017) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; Ruiz-Jimeno, A.A search for heavy resonances with masses above 1TeV, decaying to final states containing a vector boson and a Higgs boson, is presented. The search considers hadronic decays of the vector boson, and Higgs boson decays to b quarks. The decay products are highly boosted, and each collimated pair of quarks is reconstructed as a single, massive jet. The analysis is performed using a data sample collected in 2016 by the CMS experiment at the LHC in proton-proton collisions at a center-of-mass energy of 13TeV, corresponding to an integrated luminosity of 35.9fb-1. The data are consistent with the background expectation and are used to place limits on the parameters of a theoretical model with a heavy vector triplet. In the benchmark scenario with mass-degenerate W′ and Z ′ bosons decaying predominantly to pairs of standard model bosons, for the first time heavy resonances for masses as high as 3.3TeV are excluded at 95% confidence level, setting the most stringent constraints to date on such states decaying into a vector boson and a Higgs boson. © 2017, CERN for the benefit of the CMS collaboration.Article Citation - WoS: 13Citation - Scopus: 19Measurement of Associated Z + Charm Production in Proton–proton Collisions at √s=8tev(Springer Nature, 2018) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; De Gruttola, M.A study of the associated production of a Z boson and a charm quark jet (Z + c), and a comparison to production with a b quark jet (Z + b), in p p collisions at a centre-of-mass energy of 8TeV are presented. The analysis uses a data sample corresponding to an integrated luminosity of 19.7fb-1, collected with the CMS detector at the CERN LHC. The Z boson candidates are identified through their decays into pairs of electrons or muons. Jets originating from heavy flavour quarks are identified using semileptonic decays of c or b flavoured hadrons and hadronic decays of charm hadrons. The measurements are performed in the kinematic region with two leptons with pTℓ>20GeV, | ηℓ| < 2.1 , 71<m111GeV, and heavy flavour jets with pTjet>25GeV and | ηjet| < 2.5. The Z + c production cross section is measured to be σ(pp→Z+c+X)B(Z→ℓ+ℓ-)=8.8±0.5(stat)±0.6(syst)pb. The ratio of the Z + c and Z + b production cross sections is measured to be σ(pp→Z+c+X)/σ(pp→Z+b+X)=2.0±0.2(stat)±0.2(syst). The Z + c production cross section and the cross section ratio are also measured as a function of the transverse momentum of the Z boson and of the heavy flavour jet. The measurements are compared with theoretical predictions. © 2018, CERN for the benefit of the CMS collaboration.Article Citation - WoS: 13Citation - Scopus: 15Study of Dijet Events With a Large Rapidity Gap Between the Two Leading Jets in Pp Collisions at √s=7tev(Springer Nature, 2018) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Brandstetter, J.; Bloch, P.Events with no charged particles produced between the two leading jets are studied in proton-proton collisions at s=7TeV. The jets were required to have transverse momentum pTjet>40GeV and pseudorapidity 1.5 < | ηjet| < 4.7 , and to have values of ηjet with opposite signs. The data used for this study were collected with the CMS detector during low-luminosity running at the LHC, and correspond to an integrated luminosity of 8pb-1. Events with no charged particles with pT> 0.2 GeV in the interval - 1 < η< 1 between the jets are observed in excess of calculations that assume no color-singlet exchange. The fraction of events with such a rapidity gap, amounting to 0.5–1% of the selected dijet sample, is measured as a function of the pT of the second-leading jet and of the rapidity separation between the jets. The data are compared to previous measurements at the Tevatron, and to perturbative quantum chromodynamics calculations based on the Balitsky–Fadin–Kuraev–Lipatov evolution equations, including different models of the non-perturbative gap survival probability. © 2018, CERN for the benefit of the CMS collaboration.Article Citation - WoS: 31Citation - Scopus: 35Electroweak Production of Two Jets in Association With a Z Boson in Proton–proton Collisions at √s= 13 Tev(Springer Nature, 2018) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; Albajar, C.A measurement of the electroweak (EW) production of two jets in association with a Z boson in proton-proton collisions at s=13TeV is presented, based on data recorded in 2016 by the CMS experiment at the LHC corresponding to an integrated luminosity of 35.9fb--1. The measurement is performed in the ℓℓjj final state with ℓ including electrons and muons, and the jets j corresponding to the quarks produced in the hard interaction. The measured cross section in a kinematic region defined by invariant masses mℓℓ>50GeV, mjj>120GeV, and transverse momenta pTj>25GeV is σEW(ℓℓjj)=534±20(stat)±57(syst) fb, in agreement with leading-order standard model predictions. The final state is also used to perform a search for anomalous trilinear gauge couplings. No evidence is found and 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 -2.6<cWWW/Λ2<2.6TeV-2 and -8.4<cW/Λ2<10.1TeV-2. The additional jet activity of events in a signal-enriched region is also studied, and the measurements are in agreement with predictions. © 2018, CERN for the benefit of the CMS collaboration.Article Citation - WoS: 16Citation - Scopus: 18Studies of Bs2∗(5840)0 and B S 1(5830) 0 Mesons Including the Observation of the Bs2∗(5840)0→b0ks0 Decay in Proton-Proton Collisions at √s=8tev(Springer Nature, 2018) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; Bachiller, I.Measurements of Bs2∗(5840)0 and B s 1(5830) 0 mesons are performed using a data sample of proton-proton collisions corresponding to an integrated luminosity of [InlineEquation not available: see fulltext.], collected with the CMS detector at the LHC at a centre-of-mass energy of 8TeV. The analysis studies P-wave Bs0 meson decays into B (∗) +K - and B(∗)0KS0, where the B + and B 0 mesons are identified using the decays B +→ J / ψK + and B 0→ J / ψK ∗(892) 0. The masses of the P-wave Bs0 meson states are measured and the natural width of the Bs2∗(5840)0 state is determined. The first measurement of the mass difference between the charged and neutral B ∗ mesons is also presented. The Bs2∗(5840)0 decay to B0KS0 is observed, together with a measurement of its branching fraction relative to the Bs2∗(5840)0→B+K- decay. © 2018, CERN for the benefit of the CMS collaboration.Article Citation - WoS: 39Citation - Scopus: 49Measurement of Differential Cross Sections for Z Boson Production in Association With Jets in Proton-Proton Collisions at √s=13tev(Springer Nature, 2018) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; Fouz, M.C.The production of a Z boson, decaying to two charged leptons, in association with jets in proton-proton collisions at a centre-of-mass energy of 13TeV is measured. Data recorded with the CMS detector at the LHC are used that correspond to an integrated luminosity of 2.19fb-1. The cross section is measured as a function of the jet multiplicity and its dependence on the transverse momentum of the Z boson, the jet kinematic variables (transverse momentum and rapidity), the scalar sum of the jet momenta, which quantifies the hadronic activity, and the balance in transverse momentum between the reconstructed jet recoil and the Z boson. The measurements are compared with predictions from four different calculations. The first two merge matrix elements with different parton multiplicities in the final state and parton showering, one of which includes one-loop corrections. The third is a fixed-order calculation with next-to-next-to-leading order accuracy for the process with a Z boson and one parton in the final state. The fourth combines the fully differential next-to-next-to-leading order calculation of the process with no parton in the final state with next-to-next-to-leading logarithm resummation and parton showering. © 2018, CERN for the benefit of the CMS collaboration.Article Citation - WoS: 10Citation - Scopus: 12Azimuthal Separation in Nearly Back-To Jet Topologies in Inclusive 2- and 3-Jet Events in Pp Collisions at √s=13te(Springer Nature, 2019) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; Goy Lopez, S.A measurement for inclusive 2- and 3-jet events of the azimuthal correlation between the two jets with the largest transverse momenta, Δϕ12, is presented. The measurement considers events where the two leading jets are nearly collinear (“back-to-back”) in the transverse plane and is performed for several ranges of the leading jet transverse momentum. Proton-proton collision data collected with the CMS experiment at a center-of-mass energy of 13Te and corresponding to an integrated luminosity of 35.9fb-1 are used. Predictions based on calculations using matrix elements at leading-order and next-to-leading-order accuracy in perturbative quantum chromodynamics supplemented with leading-log parton showers and hadronization are generally in agreement with the measurements. Discrepancies between the measurement and theoretical predictions are as large as 15%, mainly in the region 177 ∘< Δϕ12< 180 ∘. The 2- and 3-jet measurements are not simultaneously described by any of models. © 2019, CERN for the benefit of the CMS collaboration.Article Citation - WoS: 22Citation - Scopus: 30Evidence for Ww Production From Double-Parton Interactions in Proton–proton Collisions at √s=13tev(Springer Nature, 2020) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Bergauer, T.; Brandstetter, J.; Snigirev, A.A search for WW production from double-parton scattering processes using same-charge electron-muon and dimuon events is reported, based on proton-proton collision data collected at a center-of-mass energy of 13TeV. The analyzed data set corresponds to an integrated luminosity of 77.4fb-1, collected using the CMS detector at the LHC in 2016 and 2017. Multivariate classifiers are used to discriminate between the signal and the dominant background processes. A maximum likelihood fit is performed to extract the signal cross section. This leads to the first evidence for WW production via double-parton scattering, with a significance of 3.9 standard deviations. The measured inclusive cross section is 1.41±0.28(stat)±0.28(syst)pb. © 2020, CERN for the benefit of the CMS collaboration.