Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Citation - WoS: 90Citation - Scopus: 98Search for High-Mass Diphoton Resonances in Proton–proton Collisions at 13 Tev and Combination With 8 Tev Search(Elsevier B.V., 2017) Khachatryan, V.; Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Elumakhov, D.A search for the resonant production of high-mass photon pairs is presented. The search focuses on spin-0 and spin-2 resonances with masses between 0.5 and 4.5 TeV, and with widths, relative to the mass, between 1.4×10−4 and 5.6×10−2. The data sample corresponds to an integrated luminosity of 12.9 fb−1 of proton–proton collisions collected with the CMS detector in 2016 at a center-of-mass energy of 13 TeV. No significant excess is observed relative to the standard model expectation. The results of the search are combined statistically with those previously obtained in 2012 and 2015 at s=8 and 13 TeV, respectively, corresponding to integrated luminosities of 19.7 and 3.3 fb−1, to derive exclusion limits on scalar resonances produced through gluon–gluon fusion, and on Randall–Sundrum gravitons. The lower mass limits for Randall–Sundrum gravitons range from 1.95 to 4.45 TeV for coupling parameters between 0.01 and 0.2. These are the most stringent limits on Randall–Sundrum graviton production to date. © 2017 The AuthorArticle Citation - WoS: 24Citation - Scopus: 22Search for Top Squark Pair Production in Compressed-Mass Scenarios in Proton-Proton Collisions at S=8 Tev Using the Αt Variable(Elsevier B.V., 2017) Khachatryan, V.; Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Cabrillo, I.J.An inclusive search is performed for supersymmetry in final states containing jets and an apparent imbalance in transverse momentum, p→T miss, due to the production of unobserved weakly interacting particles in pp collisions at a centre-of-mass energy of 8 TeV. The data, recorded with the CMS detector at the CERN LHC, correspond to an integrated luminosity of 18.5 fb−1. The dimensionless kinematic variable αT is used to discriminate between events with genuine p→T miss associated with unobserved particles and spurious values of p→T miss arising from jet energy mismeasurements. No excess of event yields above the expected standard model backgrounds is observed. The results are interpreted in terms of constraints on the parameter space of several simplified models of supersymmetry that assume the pair production of top squarks. The search provides sensitivity to a broad range of top squark (t˜) decay modes, including the two-body decay t˜→cχ˜1°, where c is a charm quark and χ˜1° is the lightest neutralino, as well as the four-body decay t˜→bff¯′χ˜1°, where b is a bottom quark and f and f¯′ are fermions produced in the decay of an intermediate off-shell W boson. These modes dominate in scenarios in which the top squark and lightest neutralino are nearly degenerate in mass. For these modes, top squarks with masses as large as 260 and 225 GeV are excluded, respectively, for the two- and four-body decays. © 2017 The AuthorArticle Citation - WoS: 44Citation - Scopus: 53Measurement of the Cross Section for Electroweak Production of Zγ in Association With Two Jets and Constraints on Anomalous Quartic Gauge Couplings in Proton–proton Collisions at S=8 Tev(Elsevier B.V., 2017) Khachatryan, V.; Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Asilar, E.; Bergauer, T.; Piedra Gomez, J.A measurement is presented of the cross section for the electroweak production of a Z boson and a photon in association with two jets in proton–proton collisions at s=8 TeV. The Z bosons are identified through their decays to electron or muon pairs. The measurement is based on data collected with the CMS detector corresponding to an integrated luminosity of 19.7 fb−1. The electroweak contribution has a significance of 3.0 standard deviations, and the measured fiducial cross section is 1.86−0.75 +0.90(stat)−0.26 +0.34(syst)±0.05(lumi) fb, while the summed electroweak and quantum chromodynamic total cross section in the same region is observed to be 5.94−1.35 +1.53(stat)−0.37 +0.43(syst)±0.13(lumi) fb. Both measurements are consistent with the leading-order standard model predictions. Limits on anomalous quartic gauge couplings are set based on the Zγ mass distribution. © 2017 The AuthorArticle 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: 36Citation - Scopus: 38Search for Single Production of Vector-Like Quarks Decaying Into a B Quark and a W Boson in Proton–proton Collisions at S=13tev(Elsevier B.V., 2017) Belknap, D.A.; Buchanan, J.; Caillol, C.; Dasu, S.; Dodd, L.; Duric, S.; Redondo, I.A search is presented for a heavy vector-like quark, decaying into a b quark and a W boson, which is produced singly in association with a light flavor quark and a b quark. The analysis is performed using a data sample of proton–proton collisions at a center-of-mass energy of s=13TeV collected at the LHC in 2015. The data set used in the analysis corresponds to an integrated luminosity of 2.3fb−1. The search is carried out using events containing one electron or muon, at least one b-tagged jet with large transverse momentum, at least one jet in the forward region of the detector, and missing transverse momentum. No excess over the standard model prediction is observed. Upper limits are placed on the production cross section of heavy exotic quarks: a T quark with a charge of 2/3, and a Y quark with a charge of −4/3. For Y quarks with coupling of 0.5 and B(Y→bW)=100%, the observed (expected) lower mass limits are 1.40 (1.0)TeV. This is the most stringent limit to date on the single production of the Y vector-like quark. © 2017 The Author(s)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: 27Citation - Scopus: 32Measurement of Differential Cross Sections for Z Boson Pair Production in Association With Jets at S=8 and 13 Tev(Elsevier B.V., 2019) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; Okhotnikov, V.This Letter reports measurements of differential cross sections for the production of two Z bosons in association with jets in proton–proton collisions at s=8 and 13 TeV. The analysis is based on data samples collected at the LHC with the CMS detector, corresponding to integrated luminosities of 19.7 and 35.9fb−1 at 8 and 13 TeV, respectively. The measurements are performed in the leptonic decay modes ZZ→ℓ+ℓ−ℓ′+ℓ′−, where ℓ,ℓ′=e,μ. The differential cross sections as a function of the jet multiplicity, the transverse momentum pT, and pseudorapidity of the pT -leading and subleading jets are presented. In addition, the differential cross sections as a function of variables sensitive to the vector boson scattering, such as the invariant mass of the two pT -leading jets and their pseudorapidity separation, are reported. The results are compared to theoretical predictions and found in good agreement within the theoretical and experimental uncertainties. © 2018 The Author(s)Article Citation - WoS: 37Citation - Scopus: 57A Search for Pair Production of New Light Bosons Decaying Into Muons in Proton-Proton Collisions at 13 Tev(Elsevier B.V., 2019) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Asilar, E.; Bergauer, T.; Romero, L.A search for new light bosons decaying into muon pairs is presented using a data sample corresponding to an integrated luminosity of 35.9fb−1 of proton-proton collisions at a center-of-mass energy s=13TeV, collected with the CMS detector at the CERN LHC. The search is model independent, only requiring the pair production of a new light boson and its subsequent decay to a pair of muons. No significant deviation from the predicted background is observed. A model independent limit is set on the product of the production cross section times branching fraction to dimuons squared times acceptance as a function of new light boson mass. This limit varies between 0.15 and 0.39 fb over a range of new light boson masses from 0.25 to 8.5 GeV. It is then interpreted in the context of the next-to-minimal supersymmetric standard model and a dark supersymmetry model that allows for nonnegligible light boson lifetimes. In both cases, there is significant improvement over previously published limits. © 2019 The Author(s)Article Citation - WoS: 115Citation - Scopus: 165A Measurement of the Higgs Boson Mass in the Diphoton Decay Channel(Elsevier B.V., 2020) Sirunyan, A.M.; Tumasyan, A.; Adam, W.; Ambrogi, F.; Bergauer, T.; Dragicevic, M.; Borchsh, V.A measurement of the mass of the Higgs boson in the diphoton decay channel is presented. This analysis is based on 35.9fb−1 of proton-proton collision data collected during the 2016 LHC running period, with the CMS detector at a centre-of-mass energy of 13 TeV. A refined detector calibration and new analysis techniques have been used to improve the precision of this measurement. The Higgs boson mass is measured to be mH=125.78±0.26GeV. This is combined with a measurement of mH already performed in the H→ZZ→4ℓ decay channel using the same data set, giving mH=125.46±0.16GeV. This result, when further combined with an earlier measurement of mH using data collected in 2011 and 2012 with the CMS detector, gives a value for the Higgs boson mass of mH=125.38±0.14GeV. This is currently the most precise measurement of the mass of the Higgs boson. © 2020 The Author(s)