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Article Citation - WoS: 64Citation - Scopus: 70Measurement of Differential T(t)over-Bar Production Cross Sections in the Full Kinematic Range Using Lepton Plus Jets Events From Proton-Proton Collisions at Root S=13 Tev(American Physical Society, 2021) Karapınar, Güler; CMS CollaborationMeasurements of differential and double-differential cross sections of top-quark pair (t (t) over bar) production arc presented in the lepton + jets channels with a single electron or muon and jets in the final state. The analysis combines for the first time signatures of top quarks with low transverse momentum p(T), where the top-quark decay products can be identified as separated jets and isolated leptons, and with high p(T), where the decay products are collimated and overlap. The measurements arc based on proton-proton collision data at is - = 13 TeV collected by the CMS experiment at the LHC, corresponding to an integrated luminosity of 137 fb(-1). The cross sections are presented at the parton and particle levels, where the latter minimizes extrapolations based on theoretical assumptions. Most of the measured differential cross sections are well described by standard model predictions with the exception of some double-differential distributions. The inclusive t (t) over bar production cross section is measured to be sigma(t (t) over bar) = 791 +/- 25 pb, which constitutes the most precise measurement in the lepton + jets channel to date.Article Citation - WoS: 23Citation - Scopus: 32Search for a Heavy Higgs Boson Decaying Into Two Lighter Higgs Bosons in the Tau Tau Bb Final State at 13tev(Springer, 2021) Karapınar, Güler; CMS CollaborationA search for a heavy Higgs boson H decaying into the observed Higgs boson h with a mass of 125 GeV and another Higgs boson h(S) is presented. The h and h(S) bosons are required to decay into a pair of tau leptons and a pair of b quarks, respectively. The search uses a sample of proton-proton collisions collected with the CMS detector at a center-of-mass energy of 13TeV, corresponding to an integrated luminosity of 137 fb(-1). Mass ranges of 240-3000 GeV for m(H) and 60-2800 GeV for m(hS) are explored in the search. No signal has been observed. Model independent 95% confidence level upper limits on the product of the production cross section and the branching fractions of the signal process are set with a sensitivity ranging from 125 fb (for m(H) = 240 GeV) to 2.7 fb (for m(H) = 1000 GeV). These limits are compared to maximally allowed products of the production cross section and the branching fractions of the signal process in the next-to-minimal supersymmetric extension of the standard model.Article Citation - WoS: 22Citation - Scopus: 23Measurements of the Pp -> W-+/-gamma Gamma and Pp -> Z Gamma Gamma Cross Sections at Root S=13 Tev and Limits on Anomalous Quartic Gauge Couplings(Springer, 2021) Karapınar, GülerThe cross section for W or Z boson production in association with two photons is measured in proton-proton collisions at a centre-of-mass energy of 13 TeV. The data set corresponds to an integrated luminosity of 137 fb(-1) collected by the CMS experiment at the LHC. The W -> l nu and Z -> ll decay modes (where l = e, mu) are used to extract the W gamma gamma and Z gamma gamma cross sections in a phase space defined by electron (muon) with transverse momentum larger than 30 GeV and photon transverse momentum larger than 20 GeV. All leptons and photons are required to have absolute pseudorapidity smaller than 2.5. The measured cross sections in this phase space are sigma(W gamma gamma) = 13.6(-1.9)(+1.9) (stat)(-4.0)(+4.0) (syst) +/- 0.08 (PDF + scale) fb and sigma(Z gamma gamma) = 5.41(-0.55)(+0.58) (stat)(-0.70)(+0.64) (syst) +/- 0.06 (PDF + scale) fb. Limits on anomalous quartic gauge couplings are set in the framework of an effective field theory with dimension-8 operators.Correction Citation - WoS: 1Citation - Scopus: 1Article Citation - WoS: 19Citation - Scopus: 24Search for W ' Bosons Decaying To a Top and a Bottom Quark at Root S=13 Tev in the Hadronic Final State(Elsevier, 2021) Karapınar, GülerA search is performed for W ' bosons decaying to a top and a bottom quark in the all-hadronic final state, in proton-proton collisions at a center-of-mass energy of 13TeV. The analyzed data were collected by the CMS experiment between 2016 and 2018 and correspond to an integrated luminosity of 137fb(-1). Deep neural network algorithms are used to identify the jet initiated by the bottom quark and the jet containing the decay products of the top quark when the W ' boson from the top quark decays hadronically. No excess above the estimated standard model background is observed. Upper limits on the production cross sections of W ' bosons decaying to a top and a bottom quark are set. Both left- and right-handed W ' bosons with masses below 3.4TeV are excluded at 95% confidence level, and the most stringent limits to date on W ' bosons decaying to a top and a bottom quark in the all-hadronic final state are obtained. (C) 2021 The Author(s). Published by Elsevier B.V.Article Citation - WoS: 16Citation - Scopus: 16Dependence of Inclusive Jet Production on the Anti-K(t) Distance Parameter in Pp Collisions at Root S=13 Tev(Springer, 2020) CMS Collaboration; Karapınar, GülerThe dependence of inclusive jet production in proton-proton collisions with a center-of-mass energy of 13 TeV on the distance parameter R of the anti-k(T) algorithm is studied using data corresponding to integrated luminosities up to 35.9 fb(-1) collected by the CMS experiment in 2016. The ratios of the inclusive cross sections as functions of transverse momentum p(T) and rapidity y, for R in the range 0.1 to 1.2 to those using R = 0.4 are presented in the region 84 < p(T)< 1588 GeV and |y|< 2.0. The results are compared to calculations at leading and next-to-leading order in the strong coupling constant using different parton shower models. The variation of the ratio of cross sections with R is well described by calculations including a parton shower model, but not by a leading-order quantum chromodynamics calculation including nonperturbative effects. The agreement between the data and the theoretical predictions for the ratios of cross sections is significantly improved when next-to-leading order calculations with nonperturbative effects are used.Article Citation - WoS: 29Citation - Scopus: 31Studies of Charm and Beauty Hadron Long-Range Correlations in Pp and Ppb Collisions at Lhc Energies(Elsevier, 2021) Karapınar, GülerMeasurements of the second Fourier harmonic coefficient (v(2)) of the azimuthal distributions of prompt and nonprompt D-0 mesons produced in pp and pPb collisions are presented. Nonprompt D-0 mesons come from beauty hadron decays. The data samples are collected by the CMS experiment at nucleon-nucleon center-of-mass energies of 13 and 8.16 TeV, respectively. In high multiplicity pp collisions, v(2) signals for prompt charm hadrons are reported for the first time, and are found to be comparable to those for light-flavor hadron species over a transverse momentum (pT) range of 2-6 GeV. Compared at similar event multiplicities, the prompt D-0 meson v(2) values in pp and pPb collisions are similar in magnitude. The v(2) values for open beauty hadrons are extracted for the first time via nonprompt D-0 mesons in pPb collisions. For pT in the range of 2-5 GeV, the results suggest that v(2) for nonprompt D-0 mesons is smaller than that for prompt D-0 mesons. These new measurements indicate a positive charm hadron v(2) in pp collisions and suggest a mass dependence in v(2) between charm and beauty hadrons in the pPb system. These results provide insights into the origin of heavy-flavor quark collectivity in small systems. (C) 2020 The Author(s). Published by Elsevier B.V.Article Citation - WoS: 35Citation - Scopus: 39Search for Top Squark Pair Production Using Dilepton Final States in Pp Collision Data Collected at Root S=13tev(Springer, 2021) CMS Collaboration; Karapınar, GülerA search is presented for supersymmetric partners of the top quark (top squarks) in final states with two oppositely charged leptons (electrons or muons), jets identified as originating from bquarks, and missing transverse momentum. The search uses data from proton-proton collisions at root s = 13 TeV collected with the CMS detector, corresponding to an integrated luminosity of 137 fb(-1). Hypothetical signal events are efficiently separated from the dominant top quark pair production background with requirements on the significance of the missing transverse momentum and on transverse mass variables. No significant deviation is observed from the expected background. Exclusion limits are set in the context of simplified supersymmetric models with pair-produced lightest top squarks. For top squarks decaying exclusively to a top quark and a lightest neutralino, lower limits are placed at 95% confidence level on the masses of the top squark and the neutralino up to 925 and 450 GeV, respectively. If the decay proceeds via an intermediate chargino, the corresponding lower limits on the mass of the lightest top squark are set up to 850 GeV for neutralino masses below 420 GeV. For top squarks undergoing a cascade decay through charginos and sleptons, the mass limits reach up to 1.4 TeV and 900 GeV respectively for the top squark and the lightest neutralino.Article Citation - WoS: 8Citation - Scopus: 49Measurement of the Inclusive and Differential Higgs Boson Production Cross Sections in the Leptonic Ww Decay Mode at P Root S=13 Tev(Springer, 2021) CMS Collaboration; Karapınar, GülerMeasurements of the fiducial inclusive and differential production cross sections of the Higgs boson in proton-proton collisions at root s = 13 TeV are performed using events where the Higgs boson decays into a pair of W bosons that subsequently decay into a final state with an electron, a muon, and a pair of neutrinos. The analysis is based on data collected with the CMS detector at the LHC during 2016-2018, corresponding to an integrated luminosity of 137 fb(-1). Production cross sections are measured as a function of the transverse momentum of the Higgs boson and the associated jet multiplicity. The Higgs boson signal is extracted and simultaneously unfolded to correct for selection efficiency and resolution effects using maximum-likelihood fits to the observed distributions in data. The integrated fiducial cross section is measured to be 86.5 +/- 9.5 fb, consistent with the Standard Model expectation of 82.5 +/- 4.2 fb. No significant deviation from the Standard Model expectations is observed in the differential measurements.Article Citation - WoS: 28Citation - Scopus: 35Measurement of the Electroweak Production of Z Gamma and Two Jets in Proton-Proton Collisions at Root S=13 Tev and Constraints on Anomalous Quartic Gauge Couplings(Amer Physical Soc, 2021) CMS Collaboration; Karapınar, GülerThe first observation of the electroweak (EW) production of a Z boson, a photon, and two forward jets (Z gamma jj) in proton-proton collisions at a center-of-mass energy of 13 TeV is presented. A data set corresponding to an integrated luminosity of 137 fb(-1), collected by the CMS experiment at the LHC in 2016-2018 is used. The measured fiducial cross section for EW Z gamma jj is sigma(Ew )= 5.21 +/- 0.52(stat)+/- 0.56(syst) fb = 5.21 +/- 0.76 fb. Single-differential cross sections in photon, leading lepton, and leading jet transverse momenta, and double-differential cross sections in mjj and vertical bar Delta eta(jj)vertical bar are also measured. Exclusion limits on anomalous quartic gauge couplings are derived at 95% confidence level in terms of the effective field theory operators M-0 to M-5, M-7, T-0 to T-2, and T-5 to T-9.