Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Other Erratum 2: Search for Dark Matter and Unparticles in Events With a Z Boson and Missing Transverse Momentum in Proton-Proton Collisions at ?s=13 Tev(Springer Verlag, 2018) CMS Collaboration; Karapınar, GülerIn the original paper, figure 10 was incorrect. The correct figure is shown below. Additionally, the unparticle entries in table 3, as well as figure 4 and 5 were labelled with incorrect values of ΛU. The entries correctly correspond to ΛU = 1 TeV.Article Citation - WoS: 32Citation - Scopus: 22Combination of Inclusive and Differential Tt¯ Charge Asymmetry Measurements Using Atlas and Cms Data at ?s = 7 and 8 Tev(Springer Verlag, 2018) CMS Collaboration; ATLAS Collaboration; Karapınar, GülerThis paper presents combinations of inclusive and differential measurements of the charge asymmetry (AC) in top quark pair (tt) events with a lepton+jets signature by the ATLAS and CMS Collaborations, using data from LHC proton-proton collisions at centreof- mass energies of 7 and 8TeV. The data correspond to integrated luminosities of about 5 and 20 fb–1for each experiment, respectively. The resulting combined LHC measurements of the inclusive charge asymmetry are AC LHC7= 0:005±0:007 (stat) ±0:006 (syst) at 7TeV and AC LHC7= 0:0055 ± 0:0023 (stat) ± 0:0025 (syst) at 8TeV. These values, as well as the combination of AC measurements as a function of the invariant mass of the [formula presented] system at 8TeV, are consistent with the respective standard model predictions.Article Citation - WoS: 30Citation - Scopus: 56Observation of Top Quark Production in Proton-Nucleus Collisions(American Physical Society, 2017) CMS Collaboration; Karapınar, GülerThe first observation of top quark production in proton-nucleus collisions is reported using proton-lead data collected by the CMS experiment at the CERN LHC at a nucleon-nucleon center-of-mass energy of sNN=8.16 TeV. The measurement is performed using events with exactly one isolated electron or muon candidate and at least four jets. The data sample corresponds to an integrated luminosity of 174 nb-1. The significance of the tt signal against the background-only hypothesis is above 5 standard deviations. The measured cross section is σtt=45±8 nb, consistent with predictions from perturbative quantum chromodynamics.Article Citation - WoS: 12Citation - Scopus: 16Search for a Heavy Composite Majorana Neutrino in the Final State With Two Leptons and Two Quarks at S=13tev(Elsevier Ltd., 2017) CMS Collaboration; Karapınar, GülerA search for physics beyond the standard model in the final state with two same-flavour leptons (electrons or muons) and two quarks produced in proton–proton collisions at s=13TeV is presented. The data were recorded by the CMS experiment at the CERN LHC and correspond to an integrated luminosity of 2.3fb−1. The observed data are in good agreement with the standard model background prediction. The results of the measurement are interpreted in the framework of a recently proposed model in which a heavy Majorana neutrino, Nℓ, stems from a composite-fermion scenario. Exclusion limits are set for the first time on the mass of the heavy composite Majorana neutrino, mNℓ, and the compositeness scale Λ. For the case mNℓ=Λ, the existence of Ne (Nμ) is excluded for masses up to 4.60 (4.70) TeV at 95% confidence level.Article Citation - WoS: 66Citation - Scopus: 69Constraints on Anomalous Higgs Boson Couplings Using Production and Decay Information in the Four-Lepton Final State(Elsevier Ltd., 2017) CMS Collaboration; Karapınar, GülerA search is performed for anomalous interactions of the recently discovered Higgs boson using matrix element techniques with the information from its decay to four leptons and from associated Higgs boson production with two quark jets in either vector boson fusion or associated production with a vector boson. The data were recorded by the CMS experiment at the LHC at a center-of-mass energy of 13TeV and correspond to an integrated luminosity of 38.6fb−1. They are combined with the data collected at center-of-mass energies of 7 and 8TeV, corresponding to integrated luminosities of 5.1 and 19.7fb−1, respectively. All observations are consistent with the expectations for the standard model Higgs boson.Article Citation - WoS: 24Citation - Scopus: 30Principal-Component Analysis of Two-Particle Azimuthal Correlations in Pbpb and Ppb Collisions at Cms(American Physical Society, 2017) CMS Collaboration; Karapınar, GülerFor the first time a principle-component analysis is used to separate out different orthogonal modes of the two-particle correlation matrix from heavy ion collisions. The analysis uses data from sNN=2.76TeV PbPb and sNN=5.02TeV pPb collisions collected by the CMS experiment at the CERN Large Hadron Collider. Two-particle azimuthal correlations have been extensively used to study hydrodynamic flow in heavy ion collisions. Recently it was shown that the expected factorization of two-particle results into a product of the constituent single-particle anisotropies is broken. The new information provided by these modes may shed light on the breakdown of flow factorization in heavy ion collisions. The first two modes ("leading" and "subleading") of two-particle correlations are presented for elliptical and triangular anisotropies in PbPb and pPb collisions as a function of pT over a wide range of event activity. The leading mode is found to be essentially equivalent to the anisotropy harmonic previously extracted from two-particle correlation methods. The subleading mode represents a new experimental observable and is shown to account for a large fraction of the factorization breaking recently observed at high transverse momentum. The principle-component analysis technique was also applied to multiplicity fluctuations. These also show a subleading mode. The connection of these new results to previous studies of factorization is discussed.Article Citation - WoS: 22Citation - Scopus: 44Search for Evidence of the Type-Iii Seesaw Mechanism in Multilepton Final States in Proton-Proton Collisions at ?s =13 Tev(American Physical Society, 2017) CMS Collaboration; Karapınar, GülerA search for a signal consistent with the type-III seesaw mechanism in events with three or more electrons or muons is presented. The data sample consists of proton-proton collisions at s=13 TeV collected by the CMS experiment at the LHC in 2016 and corresponds to an integrated luminosity of 35.9 fb-1. Selection criteria based on the number of leptons and the invariant mass of oppositely charged lepton pairs are used to distinguish the signal from the standard model background. The observations are consistent with the expectations from standard model processes. The results are used to place limits on the production of heavy fermions of the type-III seesaw model as a function of the branching ratio to each lepton flavor. In the scenario of equal branching fractions to each lepton flavor, heavy fermions with masses below 840 GeV are excluded. This is the most sensitive probe to date of the type-III seesaw mechanism.Article Citation - WoS: 70Citation - Scopus: 83Measurement of Vector Boson Scattering and Constraints on Anomalous Quartic Couplings From Events With Four Leptons and Two Jets in Proton–proton Collisions at S=13 Tev(Elsevier Ltd., 2017) CMS Collaboration; Karapınar, GülerA measurement of vector boson scattering and constraints on anomalous quartic gauge couplings from events with two Z bosons and two jets are presented. The analysis is based on a data sample of proton–proton collisions at s=13 TeV collected with the CMS detector and corresponding to an integrated luminosity of 35.9 fb−1. The search is performed in the fully leptonic final state ZZ→ℓℓℓ′ℓ′, where ℓ,ℓ′=e or μ. The electroweak production of two Z bosons in association with two jets is measured with an observed (expected) significance of 2.7 (1.6) standard deviations. A fiducial cross section for the electroweak production is measured to be σEW(pp→ZZjj→ℓℓℓ′ℓ′jj)=0.40−0.16 +0.21(stat)−0.09 +0.13(syst) fb, which is consistent with the standard model prediction. Limits on anomalous quartic gauge couplings are determined in terms of the effective field theory operators T0, T1, T2, T8, and T9. This is the first measurement of vector boson scattering in the ZZ channel at the LHC.Article Citation - WoS: 199Citation - Scopus: 207Measurements of Properties of the Higgs Boson Decaying Into the Four-Lepton Final State in Pp Collisions at ?s=13 Tev(Springer Verlag, 2017) CMS Collaboration; Karapınar, GülerProperties of the Higgs boson are measured in the H → ZZ → 4ℓ (ℓ = e, μ) decay channel. A data sample of proton-proton collisions at s=13 TeV, collected with the CMS detector at the LHC and corresponding to an integrated luminosity of 35.9 fb−1 is used. The signal strength modifier μ, defined as the ratio of the observed Higgs boson rate in the H → ZZ → 4ℓ decay channel to the standard model expectation, is measured to be μ = 1.05− 0.17 + 0.19 at mH = 125.09 GeV, the combined ATLAS and CMS measurement of the Higgs boson mass. The signal strength modifiers for the individual Higgs boson production modes are also measured. The cross section in the fiducial phase space defined by the requirements on lepton kinematics and event topology is measured to be 2. 92− 0.44 + 0.48(stat)− 0.24 + 0.28(syst)fb, which is compatible with the standard model prediction of 2.76 ± 0.14 fb. Differential cross sections are reported as a function of the transverse momentum of the Higgs boson, the number of associated jets, and the transverse momentum of the leading associated jet. The Higgs boson mass is measured to be mH = 125.26 ± 0.21 GeV and the width is constrained using the on-shell invariant mass distribution to be ΓH < 1.10 GeV, at 95% confidence level.[Figure not available: see fulltext.]Article Citation - WoS: 19Citation - Scopus: 40Search for Electroweak Production of Charginos and Neutralinos in Wh Events in Proton-Proton Collisions at ?s=13 Tev(Springer Verlag, 2017) CMS Collaboration; Karapınar, GülerResults are reported from a search for physics beyond the standard model in proton-proton collision events with a charged lepton (electron or muon), two jets identified as originating from a bottom quark decay, and significant imbalance in the transverse momentum. The search was performed using a data sample corresponding to 35.9 fb−1, collected by the CMS experiment in 2016 at s=13 TeV. Events with this signature can arise, for example, from the electroweak production of gauginos, which are predicted in models based on supersymmetry. The event yields observed in data are consistent with the estimated standard model backgrounds. Limits are obtained on the cross sections for chargino-neutralino (χ˜120) production in a simplified model of supersymmetry with the decays χ1±→W10andχ˜20→Hχ10. Values of mχ˜1± between 220 and 490 GeV are excluded at 95% confidence level by this search when the χ˜10 is massless, and values of mχ˜10 are 1 excluded up to 110 GeV for mχ˜1±≈450 GeV.