2024-03-29T12:07:05Z
https://aperta.ulakbim.gov.tr/oai2d
oai:zenodo.org:52935
2021-03-17T16:59:24Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Khachatryan, V.
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Asilar, E.
Bergauer, T.
Brandstetter, J.
Brondolin, E.
Dragicevic, M.
Eroe, J.
Flechl, M.
Friedl, M.
Fruehwirth, R.
Ghete, V. M.
Hartl, C.
Hoermann, N.
Hrubec, J.
Jeitler, M.
Knuenz, V.
Koenig, A.
Koenig, A.
2016-01-01
Integrated fiducial cross sections for the production of four leptons via the H -> 4l decays (l = e, mu) are measured in pp collisions at root s = 7 and 8TeV. Measurements are performed with data corresponding to integrated luminosities of 5.1 fb(-1) at 7TeV, and 19.7 fb(-1) at 8 TeV, collected with the CMS experiment at the LHC. Differential cross sections are measured using the 8 TeV data, and are determined as functions of the transverse momentum and rapidity of the four-lepton system, accompanying jet multiplicity, transverse momentum of the leading jet, and difference in rapidity between the Higgs boson candidate and the leading jet. A measurement of the Z -> 4l cross section, and its ratio to the H -> 4l cross section is also performed. All cross sections are measured within a fiducial phase space defined by the requirements on lepton kinematics and event topology. The integrated H -> 4l fiducial cross section is measured to be 0.56-(+0.67)(0.44) (stat) (+0.21)(-0.06) (syst) fb at 7 TeV, and 1.11(-0.35)(+ 0.41) (stat) (+ 0.14)(-0.10) (syst) fb at 8 TeV. The measurements are found to be compatible with theoretical calculations based on the standard model.
https://aperta.ulakbim.gov.trrecord/52935
oai:zenodo.org:52935
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JOURNAL OF HIGH ENERGY PHYSICS 4
Measurement of differential and integrated fiducial cross sections for Higgs boson production in the four-lepton decay channel in pp collisions at root s=7 and 8 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:28557
2021-03-17T16:33:24Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Ambrogi, F.
Asilar, E.
Bergauer, T.
Brandstetter, J.
Dragicevic, M.
Eroe, J.
Del Valle, A. Escalante
Flechl, M.
Fruehwirth, R.
Ghete, V. M.
Hrubec, J.
Jeitler, M.
Krammer, N.
Kraetschmer, I.
Liko, D.
Madlener, T.
Mikulec, I.
Mikulec, I.
2018-01-01
The pseudorapidity distributions of dijets as functions of their average transverse momentum (p(T)(ave)) are measured in proton-lead (pPb) and proton-proton (pp) collisions. The data samples were collected by the CMS experiment at the CERN LHC, at a nucleon-nucleon center-of-mass energy of 5.02 TeV. A significant modification of the pPb spectra with respect to the pp spectra is observed in all p(T)(ave) intervals investigated. The ratios of the pPb and pp distributions are compared to next-to-leading order perturbative quantum chromodynamics calculations with unbound nucleon and nuclear parton distribution functions (PDFs). These results give the first evidence that the gluon PDF at large Bjorken x in lead ions is strongly suppressed with respect to the PDF in unbound nucleons.
https://aperta.ulakbim.gov.trrecord/28557
oai:zenodo.org:28557
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PHYSICAL REVIEW LETTERS 121(6)
Constraining Gluon Distributions in Nuclei Using Dijets in Proton-Proton and Proton-Lead Collisions at root s(NN)=5.02 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:28569
2021-03-17T16:28:36Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Ambrogi, F.
Asilar, E.
Bergauer, T.
Brandstetter, J.
Dragicevic, M.
Eroe, J.
Del Valle, A. Escalante
Flech, M.
Fruehwirth, R.
Ghete, V. M.
Hrubec, J.
Jeiter, M.
Krammer, N.
Kraetschmer, I.
Liko, D.
Madlener, T.
Mikulec, I.
Mikulec, I.
2018-01-01
The first evidence of events consistent with the production of a single top quark in association with a photon is reported. The analysis is based on proton-proton collisions at root s = 13 TeV and recorded by the CMS experiment in 2016, corresponding to an integrated luminosity of 35.9 fb(-1). Events are selected by requiring the presence of a muon (mu), a photon (gamma), an imbalance in transverse momentum from an undetected neutrino (nu), and at least two jets (j) of which exactly one is identified as associated with the hadronization of a b quark. A multivariate discriminant based on topological and kinematic event properties is employed to separate signal from background processes. An excess above the backgroundonly hypothesis is observed, with a significance of 4.4 standard deviations. A fiducial cross section is measured for isolated photons with transverse momentum greater than 25 GeV in the central region of the detector. The measured product of the cross section and branching fraction is sigma(pp -> t gamma j) B (t -> mu nu b) = 115 +/- 17 (stat) +/- 30(syst) fb, which is consistent with the standard model prediction.
https://aperta.ulakbim.gov.trrecord/28569
oai:zenodo.org:28569
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PHYSICAL REVIEW LETTERS 121(22)
Evidence for the Associated Production of a Single Top Quark and a Photon in Proton-Proton Collisions at root s=13 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:52937
2021-03-17T16:56:55Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Khachatryan, V.
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Asilar, E.
Bergauer, T.
Brandstetter, J.
Brondolin, E.
Dragicevic, M.
Eroe, J.
Flechl, M.
Friedl, M.
Fruehwirth, R.
Ghete, V. M.
Hartl, C.
Hoermann, N.
Hrubec, J.
Jeitler, M.
Knuenz, V.
Koenig, A.
Koenig, A.
2016-01-01
are reported from a search for the top squark (t) over tilde (1) , the lighter of the two supersymmetric partners of the top quark. The data sample corresponds to 19.7 fb(-1) of proton-proton collisions at root sv - 8 TeV collected with the CMS detector at the LHC. The search targets (t) over tilde (1)-> b (x(1)) over tilde (+/-) and (t) over tilde (1)-> t((*)) (x) over tilde (0) decay modes, where (x(1)) over tilde (+/-) and (x) over tilde (0) are the lightest chargino and neutralino, respectively. The reconstructed final state consists of jets, b jets, missing transverse energy, and either one or two leptons. Leading backgrounds are determined from data. No significant excess in data is observed above the expectation from standard model processes. The results exclude a region of the two-dimensional plane of possible (t) over tilde (1) and (x(1)) over tilde (0) masses. The highest excluded (t) over tilde (1) and (x(1)) over tilde (0) masses are about 700 GeV and 250 GeV, respectively.
https://aperta.ulakbim.gov.trrecord/52937
oai:zenodo.org:52937
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JOURNAL OF HIGH ENERGY PHYSICS 7
Search for direct pair production of scalar top quarks in the single- and dilepton channels in proton-proton collisions at root s=8 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:28573
2021-03-17T16:37:34Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Ambrogi, F.
Asilar, E.
Bergauer, T.
Brandstetter, J.
Brondolin, E.
Dragicevic, M.
Eroe, J.
Del Valle, A. Escalante
Flechl, M.
Friedl, M.
Fruehwirth, R.
Ghete, V. M.
Grossmann, J.
Hrubec, J.
Jeitler, M.
Koenig, A.
Krammer, N.
Krammer, N.
2018-01-01
A search for narrow resonances decaying to bottom quark-antiquark pairs is presented, using a data sample of proton-proton collisions at root s = 8 TeV corresponding to an integrated luminosity of 19.7 fb(-1). The search is extended to masses lower than those reached in typical searches for resonances decaying into jet pairs at the LHC, by taking advantage of triggers that identify jets originating from bottom quarks. No significant excess of events is observed above the background predictions. Limits are set on the product of cross section and branching fraction to bottom quarks for spin 0, 1, and 2 resonances in the mass range of 325-1200 GeV. These results improve on the limits for resonances decaying into jet pairs in the 325-500 GeV mass range.
https://aperta.ulakbim.gov.trrecord/28573
oai:zenodo.org:28573
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PHYSICAL REVIEW LETTERS 120(20)
Search for Narrow Resonances in the b-Tagged Dijet Mass Spectrum in Proton-Proton Collisions at root s=8 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108143
2021-03-17T17:04:34Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
Charged-particle spectra obtained in Pb+Pb interactions at s N N = 2.76 TeV and pp interactions at s N N = 2.76 TeV with the ATLAS detector at the LHC are presented, using data with integrated luminosities of 0.15 nb −1 and 4.2 pb −1 , respectively, in a wide transverse momentum (0 . 5 < p T < 150 GeV) and pseudorapidity (| η | < 2) range. For Pb+Pb collisions, the spectra are presented as a function of collision centrality, which is determined by the response of the forward calorimeters located on both sides of the interaction point. The nuclear modification factors R AA and R CP are presented in detail as a function of centrality, p T and η . They show a distinct p T -dependence with a pronounced minimum at about 7 GeV. Above 60 GeV, R AA is consistent with a plateau at a centrality-dependent value, within the uncertainties. The value is 0 . 55 ± 0 . 01(stat . ) ± 0 . 04(syst . ) in the most central collisions. The R AA distribution is consistent with flat | η | dependence over the whole transverse momentum range in all centrality classes.
https://aperta.ulakbim.gov.trrecord/108143
oai:zenodo.org:108143
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Journal of High Energy Physics
Measurement of charged-particle spectra in Pb+Pb collisions at s N N = 2.76 TeV with the ATLAS detector at the LHC
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108897
2021-03-17T17:18:25Z
user-scoap3-turkiye
CERN İşbirliği
2014-01-01
Abstract bulunamadı.
https://aperta.ulakbim.gov.trrecord/108897
oai:zenodo.org:108897
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Journal of High Energy Physics
Erratum: Search for new phenomena in final states with large jet multiplicities and missing transverse momentum at $ \sqrt{s} $ = 8 TeV proton-proton collisions using the ATLAS experiment
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108803
2021-03-17T17:16:52Z
user-scoap3-turkiye
CERN İşbirliği
2014-01-01
Searches for the electroweak production of charginos, neutralinos and sleptons in final states characterized by the presence of two leptons (electrons and muons) and missing transverse momentum are performed using 20.3 fb −1 of proton-proton collision data at $ \sqrt{s} $ = 8 TeV recorded with the ATLAS experiment at the Large Hadron Collider. No significant excess beyond Standard Model expectations is observed. Limits are set on the masses of the lightest chargino, next-to-lightest neutralino and sleptons for different lightest-neutralino mass hypotheses in simplified models. Results are also interpreted in various scenarios of the phenomenological Minimal Supersymmetric Standard Model.
https://aperta.ulakbim.gov.trrecord/108803
oai:zenodo.org:108803
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Journal of High Energy Physics
Search for direct production of charginos, neutralinos and sleptons in final states with two leptons and missing transverse momentum in pp collisions at $ \sqrt{s} $ = 8TeV with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108801
2021-03-17T17:16:50Z
user-scoap3-turkiye
CERN İşbirliği
2014-01-01
The production of a W boson in association with a single charm quark is studied using 4.6 fb −1 of pp collision data at $ \sqrt{s} $ = 7 TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W -boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be $ 0.96_{-0.30}^{+0.26 } $ at Q 2 = 1.9 GeV 2 , which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally, the cross-section ratio σ ( W + + $ \overline{c} $ )/ σ ( W − + c ) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the $ s-\overline{s} $ quark asymmetry.
https://aperta.ulakbim.gov.trrecord/108801
oai:zenodo.org:108801
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Journal of High Energy Physics
Measurement of the production of a W boson in association with a charm quark in pp collisions at $ \sqrt{s} $ = 7 TeV with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108455
2021-03-17T17:10:40Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
Abstract bulunamadı.
https://aperta.ulakbim.gov.trrecord/108455
oai:zenodo.org:108455
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Journal of High Energy Physics
Erratum to: Search for new physics in events with same-sign dileptons and jets in pp collisions at s = 8 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108347
2021-03-17T17:08:39Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
The multiplicity and pseudorapidity distributions of inclusive photons have been measured at forward rapidities ( 2.3<η<3.9 ) in proton–proton collisions at three center-of-mass energies, s = 0.9, 2.76 and 7 TeV using the ALICE detector. It is observed that the increase in the average photon multiplicity as a function of beam energy is compatible with both a logarithmic and a power-law dependence. The relative increase in average photon multiplicity produced in inelastic pp collisions at 2.76 and 7 TeV center-of-mass energies with respect to 0.9 TeV are 37.2 ± 0.3 % (stat) ± 8.8 % (sys) and 61.2 ± 0.3 % (stat) ± 7.6 % (sys), respectively. The photon multiplicity distributions for all center-of-mass energies are well described by negative binomial distributions. The multiplicity distributions are also presented in terms of KNO variables. The results are compared to model predictions, which are found in general to underestimate the data at large photon multiplicities, in particular at the highest center-of-mass energy. Limiting fragmentation behavior of photons has been explored with the data, but is not observed in the measured pseudorapidity range.
https://aperta.ulakbim.gov.trrecord/108347
oai:zenodo.org:108347
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European Physical Journal C 4
Inclusive photon production at forward rapidities in proton–proton collisions at s = 0.9, 2.76 and 7 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108257
2021-03-17T17:07:01Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
We have studied the transverse-momentum ( p T ) dependence of the inclusive J/ ψ production in p-Pb collisions at s N N = 5.02 TeV, in three center-of-mass rapidity ( y cms ) regions, down to zero p T . Results in the forward and backward rapidity ranges (2.03 < y cms < 3 . 53 and −4 . 46 < y cms < −2 . 96) are obtained by studying the J/ ψ decay to μ + μ − , while the mid-rapidity region (−1 . 37 < y cms < 0 . 43) is investigated by measuring the e + e − decay channel. The p T dependence of the J/ ψ production cross section and nuclear modification factor are presented for each of the rapidity intervals, as well as the J/ ψ mean p T values. Forward and mid-rapidity results show a suppression of the J/ ψ yield, with respect to pp collisions, which decreases with increasing p T . At backward rapidity no significant J/ ψ suppression is observed. Theoretical models including a combination of cold nuclear matter effects such as shadowing and partonic energy loss, are in fair agreement with the data, except at forward rapidity and low transverse momentum. The implications of the p-Pb results for the evaluation of cold nuclear matter effects on J/ ψ production in Pb-Pb collisions are also discussed.
https://aperta.ulakbim.gov.trrecord/108257
oai:zenodo.org:108257
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Journal of High Energy Physics
Rapidity and transverse-momentum dependence of the inclusive J/ ψ nuclear modification factor in p-Pb collisions at s N N = 5.02 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108501
2021-03-17T17:11:30Z
user-scoap3-turkiye
CERN İşbirliği
2014-01-01
We report on the production of inclusive ϒ (1S) and ϒ (2S) in p–Pb collisions at sNN=5.02 TeV at the LHC. The measurement is performed with the ALICE detector at backward ( −4.46<ycms<−2.96 ) and forward ( 2.03<ycms<3.53 ) rapidity down to zero transverse momentum. The production cross sections of the ϒ (1S) and ϒ (2S) are presented, as well as the nuclear modification factor and the ratio of the forward to backward yields of ϒ (1S). A suppression of the inclusive ϒ (1S) yield in p–Pb collisions with respect to the yield from pp collisions scaled by the number of binary nucleon–nucleon collisions is observed at forward rapidity but not at backward rapidity. The results are compared to theoretical model calculations including nuclear shadowing or partonic energy loss effects.
https://aperta.ulakbim.gov.trrecord/108501
oai:zenodo.org:108501
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Physics Letters B
Production of inclusive ϒ (1S) and ϒ (2S) in p–Pb collisions at sNN=5.02 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108551
2021-03-17T17:12:27Z
user-scoap3-turkiye
Bashiry, V.
2014-01-01
Exclusive Bc*→Dsνν- decay is studied in the framework of the three-point QCD sum rules approach. The two gluon condensate contributions to the correlation function are calculated and the form factors of this transition are found. The decay width and total branching ratio for this decay are also calculated.
https://aperta.ulakbim.gov.trrecord/108551
oai:zenodo.org:108551
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Advances in High Energy Physics
Investigation of the Rare Exclusive Decays in the Framework of the QCD Sum Rules
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108605
2021-03-17T17:13:23Z
user-scoap3-turkiye
Kucukakca, Yusuf
2014-01-01
In the present work, we consider a model with a fermionic field that is non-minimally coupled to gravity in the framework of teleparallel gravity. In order to determine the forms of the coupling and potential function of fermionic field for the considered model, we use the Noether symmetry approach. By applying this approach, for the Friedman–Robertson–Walker metric, we obtain the respective potential and coupling functions as a linear and power-law form of the bilinear Ψ . Furthermore, we search for the exact cosmological solution of the model. It is shown that the fermionic field plays the role of dark energy.
https://aperta.ulakbim.gov.trrecord/108605
oai:zenodo.org:108605
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European Physical Journal C 10
Teleparallel dark energy model with a fermionic field via Noether symmetry
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108685
2021-03-17T17:14:47Z
user-scoap3-turkiye
CERN İşbirliği
2014-01-01
Distributions sensitive to the underlying event in QCD jet events have been measured with the ATLAS detector at the LHC, based on 37pb-1 of proton–proton collision data collected at a centre-of-mass energy of 7 TeV . Charged-particle mean pT and densities of all-particle ET and charged-particle multiplicity and pT have been measured in regions azimuthally transverse to the hardest jet in each event. These are presented both as one-dimensional distributions and with their mean values as functions of the leading-jet transverse momentum from 20 to 800 GeV . The correlation of charged-particle mean pT with charged-particle multiplicity is also studied, and the ET densities include the forward rapidity region; these features provide extra data constraints for Monte Carlo modelling of colour reconnection and beam-remnant effects respectively. For the first time, underlying event observables have been computed separately for inclusive jet and exclusive dijet event selections, allowing more detailed study of the interplay of multiple partonic scattering and QCD radiation contributions to the underlying event. Comparisons to the predictions of different Monte Carlo models show a need for further model tuning, but the standard approach is found to generally reproduce the features of the underlying event in both types of event selection.
https://aperta.ulakbim.gov.trrecord/108685
oai:zenodo.org:108685
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European Physical Journal C 8
Measurement of the underlying event in jet events from 7 TeV proton–proton collisions with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108457
2021-03-17T17:10:43Z
user-scoap3-turkiye
Azevedo, C.D.R.
Biagi, S.
Veenhof, R.
Correia, P.M.
Silva, A.L.M.
Carramate, L.F.N.D.
Veloso, J.F.C.A.
2015-01-01
The calculated position resolutions for X-ray photons ( 1–60 keV ) in pure noble gases at atmospheric pressure are presented. In this work we show the influence of the atomic shells and the detector dimensions on the intrinsic position resolution of the used noble gas. The calculated results were obtained by using a new software tool, Degrad, and compared to the available experimental data.
https://aperta.ulakbim.gov.trrecord/108457
oai:zenodo.org:108457
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Physics Letters B
Position resolution limits in pure noble gaseous detectors for X-ray energies from 1 to 60 keV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108373
2021-03-17T17:09:06Z
user-scoap3-turkiye
Çakır, İ. T.
Kuday, S.
Çakır, O.
2015-01-01
We study the process pp→QV+X (where Q=t,b and V=g,γ, and Z) through the anomalous interactions of the new heavy quarks at the LHC. Considering the present limits on the masses and mixings, the signatures of the heavy quark anomalous interactions are discussed and analysed at the LHC for the center of mass energy of 13 TeV. An important sensitivity to anomalous couplings κgt′/Λ=0.10 TeV−1, κγt′/Λ=0.14 TeV−1, κZt′/Λ=0.19 TeV−1 and κgb′/Λ=0.15 TeV−1, κZb′/Λ=0.19 TeV−1, κγb′/Λ=0.30 TeV−1 for the mass of 750 GeV of the new heavy quarks t′ and b′ can be reached for an integrated luminosity of Lint=100 fb−1.
https://aperta.ulakbim.gov.trrecord/108373
oai:zenodo.org:108373
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Advances in High Energy Physics
Production and Decay of Up-Type and Down-Type New Heavy Quarks through Anomalous Interactions at the LHC
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108577
2021-03-17T17:12:54Z
user-scoap3-turkiye
CERN İşbirliği
2014-01-01
Event-by-event fluctuations of the mean transverse momentum of charged particles produced in pp collisions at s = 0.9, 2.76 and 7 TeV, and Pb–Pb collisions at sNN = 2.76 TeV are studied as a function of the charged-particle multiplicity using the ALICE detector at the LHC. Dynamical fluctuations indicative of correlated particle emission are observed in all systems. The results in pp collisions show little dependence on collision energy. The Monte Carlo event generators PYTHIA and PHOJET are in qualitative agreement with the data. Peripheral Pb–Pb data exhibit a similar multiplicity dependence as that observed in pp. In central Pb–Pb, the results deviate from this trend, featuring a significant reduction of the fluctuation strength. The results in Pb–Pb are in qualitative agreement with previous measurements in Au–Au at lower collision energies and with expectations from models that incorporate collective phenomena.
https://aperta.ulakbim.gov.trrecord/108577
oai:zenodo.org:108577
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European Physical Journal C 10
Event-by-event mean pT fluctuations in pp and Pb–Pb collisions at the LHC
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108153
2021-03-17T17:04:47Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
Many extensions of the Standard Model predict the existence of charged heavy long-lived particles, such as R -hadrons or charginos. These particles, if produced at the Large Hadron Collider, should be moving non-relativistically and are therefore identifiable through the measurement of an anomalously large specific energy loss in the ATLAS pixel detector. Measuring heavy long-lived particles through their track parameters in the vicinity of the interaction vertex provides sensitivity to metastable particles with lifetimes from 0.6Â ns to 30Â ns. A search for such particles with the ATLAS detector at the Large Hadron Collider is presented, based on a data sample corresponding to an integrated luminosity of 18.4 Â fb -1 of pp collisions at s=8 Â TeV. No significant deviation from the Standard Model background expectation is observed, and lifetime-dependent upper limits on R -hadrons and chargino production are set. Gluino R -hadrons with 10Â ns lifetime and masses up to 1185Â GeV are excluded at 95Â % confidence level, and so are charginos with 15Â ns lifetime and masses up to 482Â GeV.
https://aperta.ulakbim.gov.trrecord/108153
oai:zenodo.org:108153
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European Physical Journal C 9
Search for metastable heavy charged particles with large ionisation energy loss in pp collisions at s=8 Â TeV using the ATLAS experiment
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108449
2021-03-17T17:10:35Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
The production of the strange and double-strange baryon resonances ( Σ(1385)± , Ξ(1530)0 ) has been measured at mid-rapidity ( y <0.5 ) in proton–proton collisions at s = 7 TeV with the ALICE detector at the LHC. Transverse momentum spectra for inelastic collisions are compared to QCD-inspired models, which in general underpredict the data. A search for the ϕ(1860) pentaquark, decaying in the Ξπ channel, has been carried out but no evidence is seen.
https://aperta.ulakbim.gov.trrecord/108449
oai:zenodo.org:108449
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European Physical Journal C 1
Production of Σ(1385)± and Ξ(1530)0 in proton–proton collisions at s= 7 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108339
2021-03-17T17:08:31Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
We report a measurement of the parameter yCP in D0–D¯0 oscillations performed by taking advantage of quantum coherence between pairs of D0D¯0 mesons produced in e+e− annihilations near threshold. In this work, doubly-tagged D0D¯0 events, where one D decays to a CP eigenstate and the other D decays in a semileptonic mode, are reconstructed using a data sample of 2.92 fb −1 collected with the BESIII detector at the center-of-mass energy of s=3.773 GeV . We obtain yCP=(−2.0±1.3±0.7)% , where the first uncertainty is statistical and the second is systematic. This result is compatible with the current world average.
https://aperta.ulakbim.gov.trrecord/108339
oai:zenodo.org:108339
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Physics Letters B
Measurement of yCP in D0–D¯0 oscillation using quantum correlations in e+e−→D0D¯0 at s=3.773 GeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108245
2021-03-17T17:06:46Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
Various differential cross-sections are measured in top-quark pair t t ¯ events produced in proton-proton collisions at a centre-of-mass energy of s = 7 TeV at the LHC with the ATLAS detector. These differential cross-sections are presented in a data set corresponding to an integrated luminosity of 4 . 6 fb −1 . The differential cross-sections are presented in terms of kinematic variables, such as momentum, rapidity and invariant mass, of a top-quark proxy referred to as the pseudo-top-quark as well as the pseudo-top-quark pair system. The dependence of the measurement on theoretical models is minimal.
https://aperta.ulakbim.gov.trrecord/108245
oai:zenodo.org:108245
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Journal of High Energy Physics
Differential top-antitop cross-section measurements as a function of observables constructed from final-state particles using pp collisions at s = 7 TeV in the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:83251
2021-03-17T17:04:14Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Adam, W.
Bergauer, T.
Dragicevic, M.
Eroe, J.
Friedl, M.
Fruehwirth, R.
Ghete, V. M.
Hartl, C.
Hoermann, N.
Hrubec, J.
Jeitler, M.
Kiesenhofer, W.
Knuenz, V.
Krammer, M.
Kraetschmer, I.
Liko, D.
Mikulec, I.
Rabady, D.
Rahbaran, B.
Rohringer, H.
Rohringer, H.
2015-01-01
The first study of W boson production in pPb collisions is presented, for bosons decaying to a muon or electron, and a neutrino. The measurements are based on a data sample corresponding to an integrated luminosity of 34.6 nb(-1) at a nucleon-nucleon centre-of-mass energy of root(NN)-N-S = 5.02 TeV, collected by the CMS experiment. The W boson differential cross sections, lepton charge asymmetry, and forward-backward asymmetries are measured for leptons of transverse momentum exceeding 25 GeV/c, and as a function of the lepton pseudorapidity in the vertical bar eta(lab)vertical bar < 2.4 range. Deviations from the expectations based on currently available parton distribution functions are observed, showing the need for including W boson data in nuclear parton distribution global fits. (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V.
https://aperta.ulakbim.gov.trrecord/83251
oai:zenodo.org:83251
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PHYSICS LETTERS B 750 565-586
Study of W boson production in pPb collisions at root(NN)-N-S=5.02 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108171
2021-03-17T17:05:07Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
A search for heavy long-lived multi-charged particles is performed using the ATLAS detector at the LHC. Data collected in 2012 at s=8 TeV from pp collisions corresponding to an integrated luminosity of 20.3 fb -1 are examined. Particles producing anomalously high ionisation, consistent with long-lived massive particles with electric charges from |q|=2e to |q|=6e are searched for. No signal candidate events are observed, and 95 % confidence level cross-section upper limits are interpreted as lower mass limits for a Drell–Yan production model. The mass limits range between 660 and 785 GeV.
https://aperta.ulakbim.gov.trrecord/108171
oai:zenodo.org:108171
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European Physical Journal C 8
Search for heavy long-lived multi-charged particles in pp collisions at s=8 Â TeV using the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:63239
2021-03-17T17:18:41Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Chatrchyan, S.
Khachatryan, V.
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Bergauer, T.
Dragicevic, M.
Eroe, J.
Fabjan, C.
Friedl, M.
Fruehwirth, R.
Ghete, V. M.
Hoermann, N.
Hrubec, J.
Jeitler, M.
Kiesenhofer, W.
Knuenz, V.
Krammer, M.
Kraetschmer, I.
Liko, D.
Liko, D.
2014-01-01
The inclusive cross section for top-quark pair production measured by the CMS experiment in protonproton collisions at a center-of-mass energy of 7 TeV is compared to the QCD prediction at next-to-next-to-leading order with various parton distribution functions to determine the top-quark pole mass, m(t)(pole), or the strong coupling constant, alpha(S). With the parton distribution function set NNPDF2.3, a pole mass of 176.7(-3.4)(+3.8) GeV is obtained when constraining alpha(S) at the scale of the Z boson mass, m(Z), to the current world average. Alternatively, by constraining m(t)(pole) to the latest average from direct mass measurements, a value of alpha(S)(m(Z)) = 0.1151(-0.0032)(+0.0033) is extracted. This is the first determination of alpha(S) using events from top-quark production. (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved.
https://aperta.ulakbim.gov.trrecord/63239
oai:zenodo.org:63239
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PHYSICS LETTERS B 728 496-517
Determination of the top-quark pole mass and strong coupling constant from the t(t)over-bar production cross section in pp collisions at root s=7 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108833
2021-03-17T17:17:20Z
user-scoap3-turkiye
CERN İşbirliği
2014-01-01
Measurements of b -hadron lifetimes are reported using pp collision data, corresponding to an integrated luminosity of 1.0 fb −1 , collected by the LHCb detector at a centre-of-mass energy of 7 TeV. Using the exclusive decays B + → J/ ψ K + , B 0 → J/ ψ K ∗ (892) 0 , $ {B^0}\to {J \left/ {{\psi K_s^0}} \right.} $ , $ \Lambda_b^0\to {J \left/ {{\psi \varLambda }} \right.} $ and $ B_s^0\to {J \left/ {{\psi \phi }} \right.} $ the average decay times in these modes are measured to be $ \begin{array}{*{20}{c}} {{\tau_{{{B^{+}}\to {J \left/ {{\psi {K^{+}}}} \right.}}}}=1.637\pm 0.004\pm 0.003ps,} \\ {{\tau_{{{B^0}\to {J \left/ {{\psi {K^{*0 }}}} \right.}}}}=1.524\pm 0.006\pm 0.004ps,} \\ {{\tau_{{{B^0}\to {J \left/ {{\psi K_s^0}} \right.}}}}=1.499\pm 0.013\pm 0.005ps,} \\ {{\tau_{{\Lambda_b^0\to {J \left/ {{\psi \varLambda }} \right.}}}}=1.415\pm 0.027\pm 0.006ps,} \\ {{\tau_{{B_s^0\to {J \left/ {{\psi \phi }} \right.}}}}=1.480\pm 0.011\pm 0.005ps,} \\ \end{array} $ where the first uncertainty is statistical and the second is systematic. These represent the most precise lifetime measurements in these decay modes. In addition, ratios of these lifetimes, and the ratio of the decay-width difference, ΔΓ d , to the average width, Γ d , in the B 0 system, ΔΓ d / Γ d = −0 . 044 ± 0 . 025 ± 0 . 011, are reported. All quantities are found to be consistent with Standard Model expectations.
https://aperta.ulakbim.gov.trrecord/108833
oai:zenodo.org:108833
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Journal of High Energy Physics
Measurements of the B + , B 0 , $ B_s^0 $ meson and $ \Lambda_b^0 $ baryon lifetimes
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108639
2021-03-17T17:13:58Z
user-scoap3-turkiye
CERN İşbirliği
2014-01-01
This paper presents a study of the performance of the muon reconstruction in the analysis of proton–proton collisions at s=7 TeV at the LHC, recorded by the ATLAS detector in 2010. This performance is described in terms of reconstruction and isolation efficiencies and momentum resolutions for different classes of reconstructed muons. The results are obtained from an analysis of J/ψ meson and Z boson decays to dimuons, reconstructed from a data sample corresponding to an integrated luminosity of 40 pb -1 . The measured performance is compared to Monte Carlo predictions and deviations from the predicted performance are discussed.
https://aperta.ulakbim.gov.trrecord/108639
oai:zenodo.org:108639
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European Physical Journal C 9
Muon reconstruction efficiency and momentum resolution of the ATLAS experiment in proton–proton collisions at s=7 TeV in 2010
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108387
2021-03-17T17:09:21Z
user-scoap3-turkiye
Bahar, M.K.
2015-01-01
For the first time the Schrödinger equation with more general exponential cosine screened Coulomb potential in the presence of external electric field is solved approximately and analytically by applying an ansatz to eigenfunction of corresponding Hamiltonian and then energy values and wave functions are obtained. Since this potential turns into four different potential cases when considering different cases of the parameters in the potential, energies and eigenfunctions for these four different potentials are already to be found by solving Schrödinger equation with MGECSC potential. Energy values and wave functions obtained by using different values of potential parameters for each of these four different potential are compared with the results of other studies. Since the obtained general solutions in this study have been found in the presence of external electric field, the external electric field effects on systems with the mentioned four different potentials are also easily investigated. One of advantages of the present results and method is that if external electric field is equal to zero, general mathematical structure of corresponding equations does not change and then electric field effect can be eliminated. The presence or absence of electric field does not prevent solving the Schrödinger equation analytically.
https://aperta.ulakbim.gov.trrecord/108387
oai:zenodo.org:108387
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Advances in High Energy Physics
An Alternative Approach to Solutions of the MGECSC Potential in Presence of External Electric Field
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108209
2021-03-17T17:05:51Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
The transverse momentum ( p T ) dependence of the nuclear modification factor R AA and the centrality dependence of the average transverse momentum 〈 p T 〉 for inclusive J /ψ have been measured with ALICE for Pb-Pb collisions at s N N = 2.76 TeV in the e+e − decay channel at mid-rapidity (| y | < 0 . 8). The 〈 p T 〉 is significantly smaller than the one observed for pp collisions at the same centre-of-mass energy. Consistently, an increase of R AA is observed towards low p T . These observations might be indicative of a sizable contribution of charm quark coalescence to the J /ψ production. Additionally, the fraction of non-prompt J /ψ from beauty hadron decays, f B , has been determined in the region 1 . 5 < p T < 10 GeV /c in three centrality intervals. No significant centrality dependence of f B is observed. Finally, the R AA of non-prompt J /ψ is discussed and compared with model predictions. The nuclear modification in the region 4 . 5 < p T < 10 GeV /c is found to be stronger than predicted by most models.
https://aperta.ulakbim.gov.trrecord/108209
oai:zenodo.org:108209
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Journal of High Energy Physics
Inclusive, prompt and non-prompt J/ ψ production at mid-rapidity in Pb-Pb collisions at s N N = 2.76 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108343
2021-03-17T17:08:35Z
user-scoap3-turkiye
Sakalli, I.
2015-01-01
In this paper, we focus on the quantization of four-dimensional rotating linear dilaton black hole (RLDBH) spacetime describing an action, which emerges in the Einstein–Maxwell-dilaton–axion (EMDA) theory. RLDBH spacetime has a non-asymptotically flat geometry. When the rotation parameter " a " vanishes, the spacetime reduces to its static form, the so-called linear dilaton black hole (LDBH) metric. Under scalar perturbations, we show that the radial equation reduces to a hypergeometric differential equation. Using the boundary conditions of the quasinormal modes (QNMs), we compute the associated complex frequencies of the QNMs. In a particular case, QNMs are applied in the rotational adiabatic invariant quantity, and we obtain the quantum entropy/area spectra of the RLDBH. Both spectra are found to be discrete and equidistant, and independent of the a -parameter despite the modulation of QNMs by this parameter.
https://aperta.ulakbim.gov.trrecord/108343
oai:zenodo.org:108343
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European Physical Journal C 4
Quantization of rotating linear dilaton black holes
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108621
2021-03-17T17:13:39Z
user-scoap3-turkiye
Mazharimousavi, S. Habib
Halilsoy, M.
2014-01-01
The Zipoy–Voorhees–Weyl (ZVW) spacetime characterized by mass ( M ) and oblateness ( δ ) is proposed in the construction of viable thin-shell wormholes (TSWs). A departure from spherical/cylindrical symmetry yields a positive total energy in spite of the fact that the local energy density may take negative values. We show that oblateness of the bumpy sources/black holes can be incorporated as a new degree of freedom that may play a role in the resolution of the exotic matter problem in TSWs. A small velocity perturbation reveals, however, that the resulting TSW is unstable.
https://aperta.ulakbim.gov.trrecord/108621
oai:zenodo.org:108621
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European Physical Journal C 9
Thin-shell wormholes supported by total normal matter
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108217
2021-03-17T17:06:03Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
Two searches for supersymmetric particles in final states containing a same-flavour opposite-sign lepton pair, jets and large missing transverse momentum are presented. The proton–proton collision data used in these searches were collected at a centre-of-mass energy s=8 TeV by the ATLAS detector at the Large Hadron Collider and corresponds to an integrated luminosity of 20.3 fb -1 . Two leptonic production mechanisms are considered: decays of squarks and gluinos with Z bosons in the final state, resulting in a peak in the dilepton invariant mass distribution around the Z -boson mass; and decays of neutralinos (e.g. χ~20→ℓ+ℓ-χ~10 ), resulting in a kinematic endpoint in the dilepton invariant mass distribution. For the former, an excess of events above the expected Standard Model background is observed, with a significance of three standard deviations. In the latter case, the data are well-described by the expected Standard Model background. The results from each channel are interpreted in the context of several supersymmetric models involving the production of squarks and gluinos.
https://aperta.ulakbim.gov.trrecord/108217
oai:zenodo.org:108217
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European Physical Journal C 7
Search for supersymmetry in events containing a same-flavour opposite-sign dilepton pair, jets, and large missing transverse momentum in s=8 Â TeV pp collisions with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108631
2021-03-17T17:13:49Z
user-scoap3-turkiye
CERN İşbirliği
2014-01-01
The ALICE Collaboration at the LHC reports measurement of the inclusive production cross section of electrons from semi-leptonic decays of beauty hadrons with rapidity |y|<0.8 and transverse momentum 1<pT<10 GeV/c , in pp collisions at s=2.76 TeV . Electrons not originating from semi-electronic decay of beauty hadrons are suppressed using the impact parameter of the corresponding tracks. The production cross section of beauty decay electrons is compared to the result obtained with an alternative method which uses the distribution of the azimuthal angle between heavy-flavour decay electrons and charged hadrons. Perturbative QCD predictions agree with the measured cross section within the experimental and theoretical uncertainties. The integrated visible cross section, σb→e=3.47±0.40(stat)−1.33+1.12(sys)±0.07(norm) μb , was extrapolated to full phase space using Fixed Order plus Next-to-Leading Log (FONLL) calculations to obtain the total bb¯ production cross section, σbb¯=130±15.1(stat)−49.8+42.1(sys)−3.1+3.4(extr)±2.5(norm)±4.4(BR) μb .
https://aperta.ulakbim.gov.trrecord/108631
oai:zenodo.org:108631
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Physics Letters B
Beauty production in pp collisions at s=2.76 TeV measured via semi-electronic decays
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108809
2021-03-17T17:16:57Z
user-scoap3-turkiye
CERN İşbirliği
2014-01-01
Double-differential dijet cross-sections measured in pp collisions at the LHC with a 7 TeV centre-of-mass energy are presented as functions of dijet mass and half the rapidity separation of the two highest- p T jets. These measurements are obtained using data corresponding to an integrated luminosity of 4.5 fb −1 , recorded by the ATLAS detector in 2011. The data are corrected for detector effects so that cross-sections are presented at the particle level. Cross-sections are measured up to 5 TeV dijet mass using jets reconstructed with the anti- k t algorithm for values of the jet radius parameter of 0.4 and 0.6. The cross-sections are compared with next-to-leading-order perturbative QCD calculations by NLOJet++ corrected to account for non-perturbative effects. Comparisons with POWHEG predictions, using a next-to-leading-order matrix element calculation interfaced to a parton-shower Monte Carlo simulation, are also shown. Electroweak effects are accounted for in both cases. The quantitative comparison of data and theoretical predictions obtained using various parameterizations of the parton distribution functions is performed using a frequentist method. In general, good agreement with data is observed for the NLOJet++ theoretical predictions when using the CT10, NNPDF2.1 and MSTW 2008 PDF sets. Disagreement is observed when using the ABM11 and HERAPDF1.5 PDF sets for some ranges of dijet mass and half the rapidity separation. An example setting a lower limit on the compositeness scale for a model of contact interactions is presented, showing that the unfolded results can be used to constrain contributions to dijet production beyond that predicted by the Standard Model.
https://aperta.ulakbim.gov.trrecord/108809
oai:zenodo.org:108809
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Journal of High Energy Physics
Measurement of dijet cross-sections in pp collisions at 7 TeV centre-of-mass energy using the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108389
2021-03-17T17:09:22Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
The cross-section for inelastic proton-proton collisions, with at least one prompt long-lived charged particle of transverse momentum p T > 0 . 2GeV /c in the pseudorapidity range 2 . 0 < η < 4 . 5, is measured by the LHCb experiment at a centre-of-mass energy of s = 7 TeV. The cross-section in this kinematic range is determined to be σ inel acc = 55 . 0 ± 2 . 4 mb with an experimental uncertainty that is dominated by systematic contributions. Extrapolation to the full phase space, using P ythia 6, yields σ inel = 66 . 9 ± 2 . 9 ± 4 . 4 mb, where the first uncertainty is experimental and the second is due to the extrapolation.
https://aperta.ulakbim.gov.trrecord/108389
oai:zenodo.org:108389
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Journal of High Energy Physics
Measurement of the inelastic pp cross-section at a centre-of-mass energy of s = 7 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108169
2021-03-17T17:05:05Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
Using the data sets taken at center-of-mass energies above 4 GeV by the BESIII detector at the BEPCII storage ring, we search for the reaction e+e−→γISRX(3872)→γISRπ+π−J/ψ via the Initial State Radiation technique. The production of a resonance with quantum numbers JPC=1++ such as the X(3872) via single photon e+e− annihilation is forbidden, but is allowed by a next-to-leading order box diagram. We do not observe a significant signal of X(3872) , and therefore give an upper limit for the electronic width times the branching fraction ΓeeX(3872)B(X(3872)→π+π−J/ψ)<0.13 eV at the 90% confidence level. This measurement improves upon existing limits by a factor of 46. Using the same final state, we also measure the electronic width of the ψ(3686) to be Γeeψ(3686)=2213±18stat±99sys eV .
https://aperta.ulakbim.gov.trrecord/108169
oai:zenodo.org:108169
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Physics Letters B
An improved limit for Γee of X(3872) and Γee measurement of ψ(3686)
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108151
2021-03-17T17:04:43Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
Abstract bulunamadı.
https://aperta.ulakbim.gov.trrecord/108151
oai:zenodo.org:108151
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European Physical Journal C 9
Erratum to: Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at s=8 TeV with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:66385
2021-03-17T17:14:33Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Chatrchyan, S.
Chatrchyan, S.
Khachatryan, V.
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Bergauer, T.
Dragicevic, M.
Eroe, J.
Fabjan, C.
Friedl, M.
Fruehwirth, R.
Ghete, V. M.
Hartl, C.
Hoermann, N.
Hrubec, J.
Jeitler, M.
Kiesenhofer, W.
Knuenz, V.
Krammer, M.
Krammer, M.
2014-01-01
The normalised differential top quark-antiquark production cross section is measured as a function of the jet multiplicity in proton-proton collisions at a centre-of-mass energy of 7 TeV at the LHC with the CMS detector. The measurement is performed in both the dilepton and lepton+jets decay channels using data corresponding to an integrated luminosity of 5.0 fb(-1). Using a procedure to associate jets to decay products of the top quarks, the differential cross section of the t (t) over bar production is determined as a function of the additional jet multiplicity in the lepton+jets channel. Furthermore, the fraction of events with no additional jets is measured in the dilepton channel, as a function of the threshold on the jet transverse momentum. The measurements are compared with predictions from perturbative quantum chromodynamics and no significant deviations are observed.
https://aperta.ulakbim.gov.trrecord/66385
oai:zenodo.org:66385
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EUROPEAN PHYSICAL JOURNAL C 74(8)
Measurement of jet multiplicity distributions in t(t)over-bar production in pp collisions at root s=7TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108385
2021-03-17T17:09:18Z
user-scoap3-turkiye
Balachandran, A.P.
Kürkçüoǧlu, S.
de Queiroz, A.R.
Vaidya, S.
2015-01-01
It is by now clear that the infrared sector of quantum electrodynamics (QED) has an intriguingly complex structure. Based on earlier pioneering work on this subject, two of us recently proposed a simple modification of QED by constructing a generalization of the U(1) charge group of QED to the "Sky" group incorporating the well-known spontaneous Lorentz violation due to infrared photons, but still compatible in particular with locality (Balachandran and Vaidya, Eur Phys J Plus 128:118, 2013 ). It was shown that the "Sky" group is generated by the algebra of angle-dependent charges and a study of its superselection sectors has revealed a manifest description of spontaneous breaking of the Lorentz symmetry. We further elaborate this approach here and investigate in some detail the properties of charged particles dressed by the infrared photons. We find that Lorentz violation due to soft photons may be manifestly codified in an angle-dependent fermion mass, modifying therefore the fermion dispersion relations. The fact that the masses of the charged particles are not Lorentz invariant affects their spin content, and time dilation formulas for decays should also get corrections.
https://aperta.ulakbim.gov.trrecord/108385
oai:zenodo.org:108385
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European Physical Journal C 2
Spontaneous Lorentz violation: the case of infrared QED
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108553
2021-03-17T17:12:29Z
user-scoap3-turkiye
CERN İşbirliği
2014-01-01
Measurements of differential production cross-sections of a Z boson in association with b -jets in pp collisions at s = 7 TeV are reported. The data analysed correspond to an integrated luminosity of 4.6 fb −1 recorded with the ATLAS detector at the Large Hadron Collider. Particle-level cross-sections are determined for events with a Z boson decaying into an electron or muon pair, and containing b -jets. For events with at least one b -jet, the cross-section is presented as a function of the Z boson transverse momentum and rapidity, together with the inclusive b -jet cross-section as a function of b -jet transverse momentum, rapidity and angular separations between the b -jet and the Z boson. For events with at least two b -jets, the cross-section is determined as a function of the invariant mass and angular separation of the two highest transverse momentum b -jets, and as a function of the Z boson transverse momentum and rapidity. Results are compared to leading-order and next-to-leading-order perturbative QCD calculations.
https://aperta.ulakbim.gov.trrecord/108553
oai:zenodo.org:108553
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Journal of High Energy Physics
Measurement of differential production cross-sections for a Z boson in association with b-jets in 7 TeV proton-proton collisions with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108157
2021-03-17T17:04:51Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
A search for new particles that decay into top quark pairs is reported. The search is performed with the ATLAS experiment at the LHC using an integrated luminosity of 20.3 fb−1 of proton-proton collision data collected at a centre-of-mass energy of $\sqrt{s}=8$ TeV. The lepton-plus-jets final state is used, where the top pair decays to ${W}^{+}b{W}^{-}\overline{b}$ , with one W boson decaying leptonically and the other hadronically. The invariant mass spectrum of top quark pairs is examined for local excesses or deficits that are inconsistent with the Standard Model predictions. No evidence for a top quark pair resonance is found, and 95% confidence-level limits on the production rate are determined for massive states in benchmark models. The upper limits on the cross-section times branching ratio of a narrow Z′ boson decaying to top pairs range from 4.2 pb to 0.03 pb for resonance masses from 0.4 TeV to 3.0 TeV. A narrow leptophobic topcolour Z′ boson with mass below 1.8 TeV is excluded. Upper limits are set on the cross-section times branching ratio for a broad colour-octet resonance with Γ/m = 15% decaying to $t\overline{t}$ . These range from 4.8 pb to 0.03 pb for masses from 0.4 TeV to 3.0 TeV. A Kaluza-Klein excitation of the gluon in a Randall-Sundrum model is excluded for masses below 2.2 TeV.
https://aperta.ulakbim.gov.trrecord/108157
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Journal of High Energy Physics 2015(8)
A search for $t\overline{t}$ resonances using lepton-plus-jets events in proton-proton collisions at $\sqrt{s}=8$ TeV with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:82679
2021-03-17T17:03:48Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Khachatryan, V.
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Asilar, E.
Bergauer, T.
Brandstetter, J.
Brondolin, E.
Dragicevic, M.
Eroe, J.
Flechl, M.
Friedl, M.
Fruehwirth, R.
Ghete, V. M.
Hartl, C.
Hoermann, N.
Hrubec, J.
Jeitler, M.
Knuenz, V.
Koenig, A.
Koenig, A.
2015-01-01
The pseudorapidity distribution of charged hadrons in pp collisions at root s = 13 TeV is measured using a data sample obtained with the CMS detector, operated at zero magnetic field, at the CERN LHC. The yield of primary charged long-lived hadrons produced in inelastic pp collisions is determined in the central region of the CMS pixel detector (vertical bar eta vertical bar < 2) using both hit pairs and reconstructed tracks. For central pseudorapidities (vertical bar eta vertical bar < 0.5), the charged-hadron multiplicity density is dN(ch)/d eta vertical bar(vertical bar eta vertical bar) < 0.5= 5.49 +/- 0.01 (stat) +/- 0.17 (syst), a value obtained by combining the two methods. The result is compared to predictions from Monte Carlo event generators and to similar measurements made at lower collision energies. (C) 2015 CERN for the benefit of the CMS Collaboration. Published by Elsevier B.V.
https://aperta.ulakbim.gov.trrecord/82679
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PHYSICS LETTERS B 751 143-163
Pseudorapidity distribution of charged hadrons in proton-proton collisions at root s=13TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108407
2021-03-17T17:09:42Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
This paper reports on a search for narrow resonances in diboson production in the ℓℓqq¯ final state using pp collision data corresponding to an integrated luminosity of 20 fb -1 collected at s=8 TeV with the ATLAS detector at the Large Hadron Collider. No significant excess of data events over the Standard Model expectation is observed. Upper limits at the 95 % confidence level are set on the production cross section times branching ratio for Kaluza–Klein gravitons predicted by the Randall–Sundrum model and for Extended Gauge Model W′ bosons. These results lead to the exclusion of mass values below 740 and 1590 GeV for the graviton and W′ boson respectively.
https://aperta.ulakbim.gov.trrecord/108407
oai:zenodo.org:108407
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European Physical Journal C 2
Search for resonant diboson production in the ℓℓqq¯ final state in pp collisions at s=8 TeV with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108377
2021-03-17T17:09:11Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
A search for new charged massive gauge bosons, called ${W}^{\prime }$, is performed with the ATLAS detector at the LHC, in proton–proton collisions at a centre-of-mass energy of $\sqrt{s}=8\text{}\text{TeV}$, using a dataset corresponding to an integrated luminosity of $20.3{\text{fb}}^{-1}$. This analysis searches for ${W}^{\prime }$ bosons in the ${W}^{\prime }\to t\overline{b}$ decay channel in final states with electrons or muons, using a multivariate method based on boosted decision trees. The search covers masses between 0.5 and 3.0 TeV, for right-handed or left-handed ${W}^{\prime }$ bosons. No significant deviation from the Standard Model expectation is observed and limits are set on the ${W}^{\prime }\to t\overline{b}$ cross-section times branching ratio and on the ${W}^{\prime }$-boson effective couplings as a function of the ${W}^{\prime }$-boson mass using the ${\mathrm{CL}}_{s}$ procedure. For a left-handed (right-handed) ${W}^{\prime }$ boson, masses below 1.70 (1.92) TeV are excluded at 95% confidence level.
https://aperta.ulakbim.gov.trrecord/108377
oai:zenodo.org:108377
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Physics Letters B 743 C
Search for In the Lepton Plus Jets Final State in Proton–proton Collisions at a Centre-of-mass Energy of with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108811
2021-03-17T17:16:59Z
user-scoap3-turkiye
Güver, Tolga
Erkoca, Arif Emre
Reno, Mary Hall
Sarcevic, Ina
2014-01-01
We calculate the number of dark matter particles that a neutron star accumulates over its lifetime as it rotates around the center of a galaxy, when the dark matter particle is a self-interacting boson but does not self-annihilate. We take into account dark matter interactions with baryonic matter and the time evolution of the dark matter sphere as it collapses within the neutron star. We show that dark matter self-interactions play an important role in the rapid accumulation of dark matter in the core of the neutron star. We consider the possibility of determining an exclusion region of the parameter space for dark matter mass and dark matter interaction cross section with the nucleons as well as dark matter self-interaction cross section, based on the observation of old neutron stars. We show that for a dark matter density of 103 GeV/cm3and dark matter mass mχ ≲ 10 GeV, there is a potential exclusion region for dark matter interactions with nucleons that is three orders of magnitude more stringent than without self-interactions. The potential exclusion region for dark matter self-interaction cross sections is many orders of magnitude stronger than the current Bullet Cluster limit. For example, for high dark matter density regions, we find that for mχ ∼ 10 GeV when the dark matter interaction cross section with the nucleons ranges from σχn ∼ 10−52 cm2 to σχn ∼ 10−57 cm2, the dark matter self-interaction cross section limit is σχχ ≲ 10−33 cm2, which is about ten orders of magnitude stronger than the Bullet Cluster limit.
https://aperta.ulakbim.gov.trrecord/108811
oai:zenodo.org:108811
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Journal of Cosmology and Astroparticle Physics 05
On the capture of dark matter by neutron stars
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108147
2021-03-17T17:04:39Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
A search for Higgs boson pair production pp→hh is performed with 19.5 fb -1 of proton–proton collision data at s=8 TeV, which were recorded by the ATLAS detector at the Large Hadron Collider in 2012. The decay products of each Higgs boson are reconstructed as a high-momentum bb¯ system with either a pair of small-radius jets or a single large-radius jet, the latter exploiting jet substructure techniques and associated b -tagged track-jets. No evidence for resonant or non-resonant Higgs boson pair production is observed. The data are interpreted in the context of the Randall–Sundrum model with a warped extra dimension as well as the two-Higgs-doublet model. An upper limit on the cross-section for pp→GKK∗→hh→bb¯bb¯ of 3.2 (2.3) fb is set for a Kaluza–Klein graviton GKK∗ mass of 1.0 (1.5) TeV, at the 95 % confidence level. The search for non-resonant Standard Model hh production sets an observed 95 % confidence level upper limit on the production cross-section σ(pp→hh→bb¯bb¯) of 202 fb, compared to a Standard Model prediction of σ(pp→hh→bb¯bb¯)=3.6±0.5 fb.
https://aperta.ulakbim.gov.trrecord/108147
oai:zenodo.org:108147
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European Physical Journal C 9
Search for Higgs boson pair production in the bb¯bb¯ final state from pp collisions at s=8 TeVwith the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108333
2021-03-17T17:08:25Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
An angular analysis of the B 0 → K * 0 e + e − decay is performed using a data sample, corresponding to an integrated luminosity of 3.0 fb −1 , collected by the LHCb experiment in pp collisions at centre-of-mass energies of 7 and 8 TeV during 2011 and 2012. For the first time several observables are measured in the dielectron mass squared ( q 2 ) interval between 0.002 and 1.120 GeV 2 /c 4 . The angular observables F L and A T Re which are related to the K * 0 polarisation and to the lepton forward-backward asymmetry, are measured to be F L = 0 . 16 ± 0 . 06 ± 0 . 03 and A T Re = 0.10 ± 0.18 ± 0.05, where the first uncertainty is statistical and the second systematic. The angular observables A T (2) and A T Im which are sensitive to the photon polarisation in this q 2 range, are found to be A T (2) = − 0.23 ± 0.23 ± 0.05 and A T Im = 0.14 ± 0.22 ± 0.05. The results are consistent with Standard Model predictions.
https://aperta.ulakbim.gov.trrecord/108333
oai:zenodo.org:108333
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Journal of High Energy Physics
Angular analysis of the B 0 → K * 0 e + e − decay in the low- q 2 region
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108563
2021-03-17T17:12:38Z
user-scoap3-turkiye
CERN İşbirliği
2014-01-01
In high-energy collisions, the spatio-temporal size of the particle production region can be measured using the Bose–Einstein correlations of identical bosons at low relative momentum. The source radii are typically extracted using two-pion correlations, and characterize the system at the last stage of interaction, called kinetic freeze-out. In low-multiplicity collisions, unlike in high-multiplicity collisions, two-pion correlations are substantially altered by background correlations, e.g. mini-jets. Such correlations can be suppressed using three-pion cumulant correlations. We present the first measurements of the size of the system at freeze-out extracted from three-pion cumulant correlations in pp, p–Pb and Pb–Pb collisions at the LHC with ALICE. At similar multiplicity, the invariant radii extracted in p–Pb collisions are found to be 5–15% larger than those in pp, while those in Pb–Pb are 35–55% larger than those in p–Pb. Our measurements disfavor models which incorporate substantially stronger collective expansion in p–Pb as compared to pp collisions at similar multiplicity.
https://aperta.ulakbim.gov.trrecord/108563
oai:zenodo.org:108563
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Physics Letters B
Freeze-out radii extracted from three-pion cumulants in pp, p–Pb and Pb–Pb collisions at the LHC
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:66383
2021-03-17T17:13:29Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Khachatryan, V.
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Bergauer, T.
Dragicevic, M.
Eroe, J.
Fabjan, C.
Friedl, M.
Fruhwirth, R.
Ghete, V. M.
Hartl, C.
Hoermann, N.
Hrubec, J.
Jeitler, M.
Kiesenhofer, W.
Knuenz, V.
Krammer, M.
Kraetschmer, I.
Liko, D.
Liko, D.
2014-01-01
A search for excited quarks decaying into the gamma + jet final state is presented. The analysis is based on data corresponding to an integrated luminosity of 19.7 fb(-1) collected by the CMS experiment in proton-proton collisions at root s = 8 TeV at the LHC. Events with photons and jets with high transverse momenta are selected and the gamma + jet invariant mass distribution is studied to search for a resonance peak. The 95% confidence level upper limits on the product of cross section and branching fraction are evaluated as a function of the excited quark mass. Limits on excited quarks are presented as a function of their mass and coupling strength; masses below 3.5 TeV are excluded at 95% confidence level for unit couplings to their standard model partners. (C) 2014 The Authors. Published by Elsevier B.V.
https://aperta.ulakbim.gov.trrecord/66383
oai:zenodo.org:66383
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PHYSICS LETTERS B 738 274-293
Search for excited quarks in the gamma plus jet final state in proton-proton collisions at root s=8 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108317
2021-03-17T17:08:09Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
The mass of the top quark is measured in a data set corresponding to 4.6 fb-1 of proton–proton collisions with centre-of-mass energy s=7 TeV collected by the ATLAS detector at the LHC. Events consistent with hadronic decays of top–antitop quark pairs with at least six jets in the final state are selected. The substantial background from multijet production is modelled with data-driven methods that utilise the number of identified b -quark jets and the transverse momentum of the sixth leading jet, which have minimal correlation. The top-quark mass is obtained from template fits to the ratio of three-jet to dijet mass. The three-jet mass is calculated from the three jets produced in a top-quark decay. Using these three jets the dijet mass is obtained from the two jets produced in the W boson decay. The top-quark mass obtained from this fit is thus less sensitive to the uncertainty in the energy measurement of the jets. A binned likelihood fit yields a top-quark mass of mt=175.1±1.4(stat.)±1.2(syst.)GeV.
https://aperta.ulakbim.gov.trrecord/108317
oai:zenodo.org:108317
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European Physical Journal C 4
Measurement of the top-quark mass in the fully hadronic decay channel from ATLAS data at s=7TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108045
2021-03-17T17:02:46Z
user-scoap3-turkiye
CERN İşbirliği
2015-01-01
We extract the e+e−→π+π− cross section in the energy range between 600 and 900 MeV, exploiting the method of initial state radiation. A data set with an integrated luminosity of 2.93 fb−1 taken at a center-of-mass energy of 3.773 GeV with the BESIII detector at the BEPCII collider is used. The cross section is measured with a systematic uncertainty of 0.9%. We extract the pion form factor |Fπ|2 as well as the contribution of the measured cross section to the leading-order hadronic vacuum polarization contribution to (g−2)μ . We find this value to be aμππ,LO(600–900MeV)=(368.2±2.5stat±3.3sys)⋠10−10 , which is between the corresponding values using the BaBar or KLOE data.
https://aperta.ulakbim.gov.trrecord/108045
oai:zenodo.org:108045
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Physics Letters B
Measurement of the e + e − → π + π − cross section between 600 and 900 MeV using initial state radiation
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:108485
2021-03-17T17:11:12Z
user-scoap3-turkiye
CERN İşbirliği
2014-01-01
Measurements of the branching fractions of and decays are performed using a data sample corresponding to of proton-proton collision data collected with the LHCb detector at a centre-of-mass energy of , where the mesons are econstructed in the final state. The first observation of the decay and the first evidence for the decay are reported with branching fractions where the first uncertainties are statistical and the second are systematic. In addition, an upper limit of is set at confidence level.
https://aperta.ulakbim.gov.trrecord/108485
oai:zenodo.org:108485
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New Journal of Physics 12
Observation of and evidence for decays
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:106659
2021-03-17T16:35:32Z
user-scoap3-turkiye
CERN İşbirliği
2018-01-01
We report the first measurements of absolute branching fractions for the W-exchange-only processes ${\Lambda }_{c}^{+}\to {\Xi }^{0}{K}^{+}$ and ${\Lambda }_{c}^{+}\to \Xi {\left(1530\right)}^{0}{K}^{+}$ with the double-tag technique, by analyzing an ${e}^{+}{e}^{-}$ collision data sample, that corresponds to an integrated luminosity of 567 pb$^{−1}$ collected at a center-of-mass energy of 4.6 GeV by the BESIII detector. The branching fractions are measured to be $B\left({\Lambda }_{c}^{+}\to {\Xi }^{0}{K}^{+}\right)=\left(5.90±0.86±0.39\right)×{10}^{-3}$ and $B\left({\Lambda }_{c}^{+}\to \Xi {\left(1530\right)}^{0}{K}^{+}\right)=\left(5.02±0.99±0.31\right)×{10}^{-3}$, where the first uncertainties are statistical and the second systematic. Our results are more precise than the previous relative measurements.
https://aperta.ulakbim.gov.trrecord/106659
oai:zenodo.org:106659
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Physics Letters B 783 C
Measurements of absolute branching fractions for And Ξ(1530)
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:106015
2021-03-17T16:23:19Z
user-scoap3-turkiye
Faisel, Gaber
Tandean, Jusak
2019-01-01
The anomalous results of recent measurements on various $b\to s{\mu }^{+}{\mu }^{-}$ processes could be initial evidence of physics beyond the standard model (SM). Assuming this to be the case, we entertain the possibility that the underlying new physics also affects the rare nonleptonic decays of the ${\overline{B}}_{s}^{0}$ meson. We consider in particular new physics arising from the interactions of a heavy ${Z}^{\prime }$ boson and investigate their influence on the decay modes ${\overline{B}}_{s}^{0}\to \left(\eta ,{\eta }^{\prime },\varphi \right)\omega $, which receive sizable QCD- and electroweak-penguin contributions. These decays are not yet observed, and their rates are estimated to be relatively small in the SM. Taking into account the pertinent constraints, we find that the ${Z}^{\prime }$ effects can greatly increase the rates of ${\overline{B}}_{s}^{0}\to \left(\eta ,\varphi \right)\omega $, by as much as two orders of magnitude, with respect to the SM expectations. We have previously shown that ${\overline{B}}_{s}^{0}\to \left(\eta ,\varphi \right){\pi }^{0}$, with similarly suppressed SM rates, could also undergo substantial ${Z}^{\prime }$-induced enhancement. These rare modes can therefore serve as complementary probes of the potential new physics which may be responsible for the $b\to s{\mu }^{+}{\mu }^{-}$ anomalies.
https://aperta.ulakbim.gov.trrecord/106015
oai:zenodo.org:106015
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Physical Review D 99(7)
Rare nonleptonic ${\overline{B}}_{s}^{0}$ decays as probes of new physics behind $b\to s\mu \overline{\mu }$ anomalies
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:29255
2021-03-17T16:41:41Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Ambrogi, F.
Asilar, E.
Bergauer, T.
Brandstetter, J.
Brondolin, E.
Dragicevic, M.
Ero, J.
Flechl, M.
Friedl, M.
Fruhwirth, R.
Ghete, V. M.
Grossmann, J.
Hrubec, J.
Jeitler, M.
Konig, A.
Krammer, N.
Kratschmer, I.
Kratschmer, I.
2018-01-01
A measurement of the H -> tau tau signal strength is performed using events recorded in proton-proton collisions by the CMS experiment at the LHC in 2016 at a center-of-mass energy of 13TeV. The data set corresponds to an integrated luminosity of 35.9 fb(-1). The H -> tau tau signal is established with a significance of 4.9 standard deviations, to be compared to an expected significance of 4.7 standard deviations. The best fit of the product of the observed H -> tau tau signal production cross section and branching fraction is 1.09(-0.2)(6+0.27) times the standard model expectation. The combination with the corresponding measurement performed with data collected by the CMS experiment at center-of-mass energies of 7 and 8 TeV leads to an observed significance of 5.9 standard deviations, equal to the expected significance. This is the first observation of Higgs boson decays to tau leptons by a single experiment. (c) 2018 The Author(s). Published by Elsevier B.V.
https://aperta.ulakbim.gov.trrecord/29255
oai:zenodo.org:29255
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PHYSICS LETTERS B 779 283-316
Observation of the Higgs boson decay to a pair of tau leptons with the CMS detector
info:eu-repo/semantics/article
publication-article
oai:aperta.ulakbim.gov.tr:240512
2022-10-07T16:49:40Z
user-scoap3-turkiye
CERN İşbirliği
2021-01-01
Several extensions of the Standard Model predict the production of dark matter particles at the LHC. An uncharted signature of dark matter particles produced in association with $VV={W}^{±}{W}^{\mp }$ or $ZZ$ pairs from a decay of a dark Higgs boson $s$ is searched for using $139\text{}\text{}{\mathrm{fb}}^{-1}$ of $pp$ collisions recorded by the ATLAS detector at a center-of-mass energy of 13 TeV. The $s\to V\left(q\overline{q}\right)V\left(q\overline{q}\right)$ decays are reconstructed with a novel technique aimed at resolving the dense topology from boosted $VV$ pairs using jets in the calorimeter and tracking information. Dark Higgs scenarios with ${m}_{s}>160\text{}\text{}\mathrm{GeV}$ are excluded.
https://aperta.ulakbim.gov.trrecord/240512
oai:aperta.ulakbim.gov.tr:240512
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Physical Review Letters 126(12)
Search for Dark Matter Produced in Association with a Dark Higgs Boson Decaying into ${W}^{±}{W}^{\mp }$ or $ZZ$ in Fully Hadronic Final States from $\sqrt{s}=13\text{}\text{}\mathrm{TeV}$ $pp$ Collisions Recorded with the ATLAS Detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:107393
2021-03-17T16:49:54Z
user-scoap3-turkiye
CERN İşbirliği
2017-01-01
Measurements of jet activity in top-quark pair events produced in proton–proton collisions are presented, using 3.2 fb -1 of pp collision data at a centre-of-mass energy of 13 TeV collected by the ATLAS experiment at the Large Hadron Collider. Events are chosen by requiring an opposite-charge eμ pair and two b -tagged jets in the final state. The normalised differential cross-sections of top-quark pair production are presented as functions of additional-jet multiplicity and transverse momentum, pT . The fraction of signal events that do not contain additional jet activity in a given rapidity region, the gap fraction, is measured as a function of the pT threshold for additional jets, and is also presented for different invariant mass regions of the eμbb¯ system. All measurements are corrected for detector effects and presented as particle-level distributions compared to predictions with different theoretical approaches for QCD radiation. While the kinematics of the jets from top-quark decays are described well, the generators show differing levels of agreement with the measurements of observables that depend on the production of additional jets.
https://aperta.ulakbim.gov.trrecord/107393
oai:zenodo.org:107393
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European Physical Journal C 4
Measurement of jet activity produced in top-quark events with an electron, a muon and two b -tagged jets in the final state in pp collisions at s=13 TeV with the ATLAS detector
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publication-article
oai:zenodo.org:105415
2021-03-17T16:11:29Z
user-scoap3-turkiye
CERN İşbirliği
2020-01-01
Using a data sample of $\left(448.1±2.9\right)×{10}^{6}\text{}\text{}\psi \left(3686\right)$ decays collected by the BESIII detector at the Beijing Electron Positron Collider (BEPCII), we observe the decays ${\chi }_{cJ}\to \varphi \varphi \eta \left(J=0,1,2\right)$, where the ${\chi }_{cJ}$ are produced via the radiative processes $\psi \left(3686\right)\to \gamma {\chi }_{cJ}$. The branching fractions are measured to be $B\left({\chi }_{c0}\to \varphi \varphi \eta \right)=\left(8.41±0.74±0.62\right)×{10}^{-4}$, $B\left({\chi }_{c1}\to \varphi \varphi \eta \right)=\left(2.96±0.43±0.22\right)×{10}^{-4}$, and $B\left({\chi }_{c2}\to \varphi \varphi \eta \right)=\left(5.33±0.52±0.39\right)×{10}^{-4}$, where the first uncertainties are statistical, and the second are systematic. We also search for intermediate states in the $\varphi \varphi $ or $\eta \varphi $ subsystems, but no significant structure is seen due to the limited statistics.
https://aperta.ulakbim.gov.trrecord/105415
oai:zenodo.org:105415
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Physical Review D 101(1)
Observation of the decays ${\chi }_{cJ}\to \varphi \varphi \eta $
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:105987
2021-03-17T16:22:52Z
user-scoap3-turkiye
CERN İşbirliği
2019-01-01
A search for Higgs boson pair production in the $b\overline{b}W{W}^{*}$ decay mode is performed in the $b\overline{b}\mathrm{\ell \nu qq}$ final state using 36.1 fb−1 of proton-proton collision data at a centre-of-mass energy of 13 TeV recorded with the ATLAS detector at the Large Hadron Collider. No evidence of events beyond the background expectation is found. Upper limits on the non-resonant pp → HH production cross section of 10 pb and on the resonant production cross section as a function of the HH invariant mass are obtained. Resonant production limits are set for scalar and spin-2 graviton hypotheses in the mass range 500 to 3000 GeV.
https://aperta.ulakbim.gov.trrecord/105987
oai:zenodo.org:105987
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Journal of High Energy Physics 2019(4)
Search for Higgs boson pair production in the $b\overline{b}W{W}^{*}$ decay mode at $\sqrt{s}$ = 13 TeV with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:105225
2021-03-17T16:07:55Z
user-scoap3-turkiye
CERN İşbirliği
2020-01-01
The processes $X\left(3872\right)\to {D}^{*0}{\overline{D}}^{0}+c.c.,\gamma J/\psi ,\gamma \psi \left(2S\right)$, and $\gamma {D}^{+}{D}^{-}$ are searched for in a $9.0\text{}\text{}{\mathrm{fb}}^{-1}$ data sample collected at center-of-mass energies between 4.178 and 4.278 GeV with the BESIII detector. We observe $X\left(3872\right)\to {D}^{*0}\overline{{D}^{0}}+c.c.$ and find evidence for $X\left(3872\right)\to \gamma J/\psi $ with statistical significances of $7.4\sigma $ and $3.5\sigma $, respectively. No evident signals for $X\left(3872\right)\to \gamma \psi \left(2S\right)$ and $\gamma {D}^{+}{D}^{-}$ are found, and the upper limit on the relative branching ratio ${R}_{\gamma \psi }\equiv \left\{B\left[X\left(3872\right)\to \gamma \psi \left(2S\right)\right]\right\}/\left\{B\left[X\left(3872\right)\to \gamma J/\psi \right]\right\}<0.59$ is set at 90% confidence level. Measurements of branching ratios relative to decay $X\left(3872\right)\to {\pi }^{+}{\pi }^{-}J/\psi $ are also reported for decays $X\left(3872\right)\to {D}^{*0}\overline{{D}^{0}}+c.c.,\gamma \psi \left(2S\right),\gamma J/\psi $, and $\gamma {D}^{+}{D}^{-}$, as well as the non-${D}^{*0}\overline{{D}^{0}}$ three-body decays ${\pi }^{0}{D}^{0}\overline{{D}^{0}}$ and $\gamma {D}^{0}\overline{{D}^{0}}$.
https://aperta.ulakbim.gov.trrecord/105225
oai:zenodo.org:105225
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Physical Review Letters 124(24)
Study of Open-Charm Decays and Radiative Transitions of the X(3872)
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:105147
2021-03-17T16:06:32Z
user-scoap3-turkiye
CERN İşbirliği
2020-01-01
From $1310.6×{10}^{6}\text{}\text{}J/\psi $ and $448.1×{10}^{6}\text{}\text{}\psi \left(3686\right)$ events collected with the BESIII experiment, we report the first observation of ${\Sigma }^{+}$ and ${\overline{\Sigma }}^{-}$ spin polarization in ${e}^{+}{e}^{-}\to J/\psi \left[\psi \left(3686\right)\right]\to {\Sigma }^{+}{\overline{\Sigma }}^{-}$ decays. The relative phases of the form factors $\Delta \Phi $ have been measured to be $\left(-15.5±0.7±0.5\right)°$ and $\left(21.7±4.0±0.8\right)°$ with $J/\psi $ and $\psi \left(3686\right)$ data, respectively. The nonzero value of $\Delta \Phi $ allows for a direct and simultaneous measurement of the decay asymmetry parameters of ${\Sigma }^{+}\to p{\pi }^{0}\left({\alpha }_{0}=-0.998±0.037±0.009\right)$ and ${\overline{\Sigma }}^{-}\to \overline{p}{\pi }^{0}\left({\overline{\alpha }}_{0}=0.990±0.037±0.011\right)$, the latter value being determined for the first time. The average decay asymmetry, $\left({\alpha }_{0}-{\overline{\alpha }}_{0}\right)/2$, is calculated to be $-0.994±0.004±0.002$. The $CP$ asymmetry ${A}_{CP,\Sigma }=\left({\alpha }_{0}+{\overline{\alpha }}_{0}\right)/\left({\alpha }_{0}-{\overline{\alpha }}_{0}\right)=-0.004±0.037±0.010$ is extracted for the first time, and is found to be consistent with $CP$ conservation.
https://aperta.ulakbim.gov.trrecord/105147
oai:zenodo.org:105147
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Physical Review Letters 125(5)
${\Sigma }^{+}$ and ${\overline{\Sigma }}^{-}$ Polarization in the $J/\psi $ and $\psi \left(3686\right)$ Decays
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:106093
2021-03-17T16:24:46Z
user-scoap3-turkiye
CERN İşbirliği
2019-01-01
First results on $\text{K}/\pi $ , $\text{p}/\pi $ and K/p fluctuations are obtained with the ALICE detector at the CERN LHC as a function of centrality in $\phantom{\rule{0.333333em}{0ex}}\text{Pb--Pb}\phantom{\rule{0.333333em}{0ex}}$ collisions at $\sqrt{{s}_{\mathrm{NN}}}=2.76\phantom{\rule{0.333333em}{0ex}}\text{TeV}$ . The observable ${\nu }_{\mathrm{dyn}}$ , which is defined in terms of the moments of particle multiplicity distributions, is used to quantify the magnitude of dynamical fluctuations of relative particle yields and also provides insight into the correlation between particle pairs. This study is based on a novel experimental technique, called the Identity Method, which allows one to measure the moments of multiplicity distributions in case of incomplete particle identification. The results for $\text{p}/\pi $ show a change of sign in ${\nu }_{\mathrm{dyn}}$ from positive to negative towards more peripheral collisions. For central collisions, the results follow the smooth trend of the data at lower energies and ${\nu }_{\mathrm{dyn}}$ exhibits a change in sign for $\text{p}/\pi $ and K/p.
https://aperta.ulakbim.gov.trrecord/106093
oai:zenodo.org:106093
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European Physical Journal C 79(3)
Relative particle yield fluctuations in $\phantom{\rule{0.333333em}{0ex}}\text{Pb--Pb}\phantom{\rule{0.333333em}{0ex}}$ collisions at $\sqrt{{s}_{\mathrm{NN}}}=2.76\phantom{\rule{0.333333em}{0ex}}\text{TeV}$
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:105815
2021-03-17T16:19:29Z
user-scoap3-turkiye
CERN İşbirliği
2019-01-01
A search is performed for localised excesses in dijet mass distributions of low-dijet-mass events produced in association with a high transverse energy photon. The search uses up to 79.8 fb$^{−1}$ of LHC proton–proton collisions collected by the ATLAS experiment at a centre-of-mass energy of 13 TeV during 2015–2017. Two variants are presented: one which makes no jet flavour requirements and one which requires both jets to be tagged as b-jets. The observed mass distributions are consistent with multi-jet processes in the Standard Model. The data are used to set upper limits on the production cross-section for a benchmark ${Z}^{\prime }$ model and, separately, on generic Gaussian-shape contributions to the mass distributions, extending the current ATLAS constraints on dijet resonances to the mass range between 225 and 1100 GeV.
https://aperta.ulakbim.gov.trrecord/105815
oai:zenodo.org:105815
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Physics Letters B 795 C
Search for low-mass resonances decaying into two jets and produced in association with a photon using Collisions at TeV with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:106751
2021-03-17T16:37:21Z
user-scoap3-turkiye
Kaya, Ali
2018-01-01
We examine the emergence of the infrared logarithms in the cosmological perturbation theory applied to the minisuperspace scalar slow-roll inflation. Not surprisingly, in the single scalar field model the curvature perturbation ζ is conserved and no $\mathrm{ln}{a}_{B}$ behavior appears, where ${a}_{B}\left(t\right)$ is the background scale factor of the universe. On the other hand, in the presence of a spectator scalar the n'th order perturbation theory gives an ${\left(\mathrm{ln}{a}_{B}\right)}^{n}$ correction to ζ. However, a nonperturbative estimate shows that ζ actually becomes the sum of a constant and a mildly evolving $\mathrm{ln}{a}_{B}$ pieces.
https://aperta.ulakbim.gov.trrecord/106751
oai:zenodo.org:106751
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Physics Letters B 782 C
Infrared logarithms in minisuperspace inflation
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:105209
2021-03-17T16:07:38Z
user-scoap3-turkiye
CERN İşbirliği
2020-01-01
The p T-differential non-linear flow modes, v 4,22, v 5,32, v 6,33 and v 6,222 for π ± , K ± , ${K}_{S}^{0}$ , p + $\overline{p}$ , Λ + $\overline{\Lambda }$ and ϕ-meson have been measured for the first time at $\sqrt{{s}_{\mathrm{NN}}}$ = 5.02 TeV in Pb-Pb collisions with the ALICE detector at the Large Hadron Collider. The results were obtained with a multi-particle technique, correlating the identified hadrons with reference charged particles from a different pseudorapidity region. These non-linear observables probe the contribution from the second and third order initial spatial anisotropy coefficients to higher flow harmonics. All the characteristic features observed in previous p T-differential anisotropic flow measurements for various particle species are also present in the non-linear flow modes, i.e. increase of magnitude with increasing centrality percentile, mass ordering at low p T and particle type grouping in the intermediate p T range. Hydrodynamical calculations (iEBE-VISHNU) that use different initial conditions and values of shear and bulk viscosity to entropy density ratios are confronted with the data at low transverse momenta. These calculations exhibit a better agreement with the anisotropic flow coefficients than the non-linear flow modes. These observations indicate that non-linear flow modes can provide additional discriminatory power in the study of initial conditions as well as new stringent constraints to hydrodynamical calculations.
https://aperta.ulakbim.gov.trrecord/105209
oai:zenodo.org:105209
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Journal of High Energy Physics 2020(6)
Non-linear flow modes of identified particles in Pb-Pb collisions at $\sqrt{{s}_{\mathrm{NN}}}$ = 5.02 TeV
info:eu-repo/semantics/article
publication-article
oai:aperta.ulakbim.gov.tr:240576
2022-10-07T16:51:39Z
user-scoap3-turkiye
Dunya, Onder
Akant, Levent
Arik, Metin
Kardas, Yelda
Sahin, Selale
Tok, Tarik
2021-01-01
We investigate a field theoretical approach to the Jordan–Brans–Dicke (JBD) theory extended with a particular potential term on a cosmological background by starting with the motivation that the Higgs field and the scale factor of the universe are related. Based on this relation, it is possible to come up with mathematically equivalent but two different interpretations. From one point of view while the universe is static, the masses of the elementary particles change with time. The other one, which we stick with throughout the manuscript, is that while the universe is expanding, particle masses are constant. Thus, a coupled Lagrangian density of the JBD field and the scale factor (the Higgs field), which exhibit a massive particle and a linearly expanding space in zeroth order respectively, is obtained. By performing a coordinate transformation in the field space for the reduced JBD action whose kinetic part is nonlinear sigma model, the Lagrangian of two scalar fields can be written as uncoupled for the Higgs mechanism. After this transformation, as a result of spontaneous symmetry breaking, the time dependent vacuum expectation value (vev) of the Higgs field and the Higgs bosons which are the particles corresponding to quantized oscillation modes about the vacuum, are found.
https://aperta.ulakbim.gov.trrecord/240576
oai:aperta.ulakbim.gov.tr:240576
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European Physical Journal C 81(1)
The Higgs field and the Jordan Brans Dicke cosmology
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:6569
2021-03-17T16:10:39Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Ambrogi, F.
Asilar, E.
Bergauer, T.
Brandstetter, J.
Dragicevic, M.
Eroe, J.
Del Valle, A. Escalante
Flechl, M.
Fruehwirth, R.
Ghete, V. M.
Hrubec, J.
Jeitler, M.
Krammer, N.
Kraetschmer, I
Liko, D.
Madlener, T.
Mikulec, I
Mikulec, I
2020-01-01
Bose-Einstein correlations of charged hadrons are measured over a broad multiplicity range, from a few particles up to about 250 reconstructed charged hadrons in proton-proton collisions at s = 13 TeV. The results are based on data collected using the CMS detector at the LHC during runs with a special low-pileup configuration. Three analysis techniques with different degrees of dependence on simulations are used to remove the non-Bose-Einstein background from the correlation functions. All three methods give consistent results. The measured lengths of homogeneity are studied as functions of particle multiplicity as well as average pair transverse momentum and mass. The results are compared with data from both CMS and ATLAS at s = 7 TeV, as well as with theoretical predictions.
https://aperta.ulakbim.gov.trrecord/6569
oai:zenodo.org:6569
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JOURNAL OF HIGH ENERGY PHYSICS 3
Bose-Einstein correlations of charged hadrons in proton-proton collisions at <mml:msqrt>s</mml:msqrt>=13 TeV
info:eu-repo/semantics/article
publication-article
oai:aperta.ulakbim.gov.tr:262791
2023-07-29T19:18:09Z
user-scoap3-turkiye
CERN İşbirliği
2022-01-01
Using $6.32\text{}\text{}{\mathrm{fb}}^{-1}$ of ${e}^{+}{e}^{-}$ collision data recorded by the BESIII detector at center-of-mass energies between 4.178 to 4.226 GeV, we present the first measurement of the decay ${D}_{s}^{+}\to {f}_{0}\left(980\right){e}^{+}{\nu }_{e},\phantom{\rule{0ex}{0ex}}{f}_{0}\left(980\right)\to {\pi }^{0}{\pi }^{0}$. The product branching fraction of ${D}_{s}^{+}\to {f}_{0}\left(980\right){e}^{+}{\nu }_{e},{f}_{0}\left(980\right)\to {\pi }^{0}{\pi }^{0}$ is measured to be $\left(7.9±1.{4}_{\mathrm{stat}}±0.{4}_{\mathrm{syst}}\right)×{10}^{-4}$, with a statistical significance of $7.8\sigma $. Furthermore, the upper limits on the product branching fractions of ${D}_{s}^{+}\to {f}_{0}\left(500\right){e}^{+}{\nu }_{e}$ with ${f}_{0}\left(500\right)\to {\pi }^{0}{\pi }^{0}$ and the branching fraction of ${D}_{s}^{+}\to {K}_{S}^{0}{K}_{S}^{0}{e}^{+}{\nu }_{e}$ are set to be $7.3×{10}^{-4}$ and $3.8×{10}^{-4}$ at 90% confidence level, respectively. Our results provide valuable inputs to the understanding of the structures of light scalar mesons.
https://aperta.ulakbim.gov.trrecord/262791
oai:aperta.ulakbim.gov.tr:262791
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Physical Review D 105(3)
Study of light scalar mesons through ${D}_{s}^{+}\to {\pi }^{0}{\pi }^{0}{e}^{+}{\nu }_{e}$ and ${K}_{S}^{0}{K}_{S}^{0}{e}^{+}{\nu }_{e}$ decays
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:106405
2021-03-17T16:30:45Z
user-scoap3-turkiye
Sonmez, Nasuf
2018-01-01
The determination of the Higgs self-coupling in the Standard Model is one of the primary motivations among all the future lepton colliders. Extending the scalar sector of the Standard Model by a new Higgs doublet with a quadratic Higgs potential gives many new features to the model, and most importantly additional Higgs self-couplings emerge. Measuring these couplings is the only way to reconstruct the shape of the scalar potential. In this study, the numerical analysis of several scattering processes is carried out for the two-Higgs-doublet model to determine Higgs self-couplings. These processes are selected among various possible combinations of additional Higgs states. The computation is carried out in the exact alignment limit (s βα = 1). The distribution of the cross sections is presented regarding the polarization of the incoming beams and up to $\sqrt{s}=3$ TeV. A strategy for extracting the Higgs self-couplings is considered in 2HDM and at the future lepton colliders. Possible final states that could be used for each of the processes are investigated using the decays of the final state particles.
https://aperta.ulakbim.gov.trrecord/106405
oai:zenodo.org:106405
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Journal of High Energy Physics 2018(10)
Measuring the triple Higgs self-couplings in two Higgs doublet model
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:106815
2021-03-17T16:38:30Z
user-scoap3-turkiye
CERN İşbirliği
2018-01-01
A search for heavy resonances decaying into a pair of $Z$ bosons leading to ${\ell }^{+}{\ell }^{-}{\ell }^{+}{\ell }^{-}$ and ${\ell }^{+}{\ell }^{-}\nu \overline{\nu }$ final states, where $\ell $ stands for either an electron or a muon, is presented. The search uses proton–proton collision data at a centre-of-mass energy of 13 $\text{TeV}$ corresponding to an integrated luminosity of 36.1 ${\text{fb}}^{-1}$ collected with the ATLAS detector during 2015 and 2016 at the Large Hadron Collider. Different mass ranges for the hypothetical resonances are considered, depending on the final state and model. The different ranges span between 200 and 2000 $\text{GeV}$ . The results are interpreted as upper limits on the production cross section of a spin-0 or spin-2 resonance. The upper limits for the spin-0 resonance are translated to exclusion contours in the context of Type-I and Type-II two-Higgs-doublet models, while those for the spin-2 resonance are used to constrain the Randall–Sundrum model with an extra dimension giving rise to spin-2 graviton excitations.
https://aperta.ulakbim.gov.trrecord/106815
oai:zenodo.org:106815
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European Physical Journal C 78(4)
Search for heavy ZZ resonances in the ${\ell }^{+}{\ell }^{-}{\ell }^{+}{\ell }^{-}$ and ${\ell }^{+}{\ell }^{-}\nu \overline{\nu }$ final states using proton–proton collisions at $\sqrt{s}=13$ $\text{TeV}$ with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:106533
2021-03-17T16:33:08Z
user-scoap3-turkiye
CERN İşbirliği
2018-01-01
Results from a search for supersymmetry in events with four or more charged leptons (electrons, muons and taus) are presented. The analysis uses a data sample corresponding to $36.1\text{}\text{}{\mathrm{fb}}^{-1}$ of proton–proton collisions delivered by the Large Hadron Collider at $\sqrt{s}=13\text{}\text{}\mathrm{TeV}$ and recorded by the ATLAS detector. Four-lepton signal regions with up to two hadronically decaying taus are designed to target a range of supersymmetric scenarios that can be either enriched in or depleted of events involving the production and decay of a $Z$ boson. Data yields are consistent with Standard Model expectations and results are used to set upper limits on the event yields from processes beyond the Standard Model. Exclusion limits are set at the 95% confidence level in simplified models of general gauge mediated supersymmetry, where Higgsino masses are excluded up to 295 GeV. In $R$-parity-violating simplified models with decays of the lightest supersymmetric particle to charged leptons, lower limits of 1.46, 1.06, and 2.25 TeV are placed on wino, slepton and gluino masses, respectively.
https://aperta.ulakbim.gov.trrecord/106533
oai:zenodo.org:106533
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Physical Review D 98(3)
Search for supersymmetry in events with four or more leptons in $\sqrt{s}=13\text{}\text{}\mathrm{TeV}$ $pp$ collisions with ATLAS
info:eu-repo/semantics/article
publication-article
oai:aperta.ulakbim.gov.tr:240172
2022-10-07T15:27:28Z
user-scoap3-turkiye
CERN İşbirliği
2021-01-01
In this paper, we present the physics performance of the ESSnuSB experiment in the standard three flavor scenario using the updated neutrino flux calculated specifically for the ESSnuSB configuration and updated migration matrices for the far detector. Taking conservative systematic uncertainties corresponding to a normalization error of $5%$ for signal and $10%$ for background, we find that there is $10\sigma $ $\left(13\sigma \right)$ CP violation discovery sensitivity for the baseline option of 540 km (360 km) at ${\delta }_{\mathrm{CP}}=±{90}^{\circ }$ . The corresponding fraction of ${\delta }_{\mathrm{CP}}$ for which CP violation can be discovered at more than $5\sigma $ is $70%$ . Regarding CP precision measurements, the $1\sigma $ error associated with ${\delta }_{\mathrm{CP}}={0}^{\circ }$ is around ${5}^{\circ }$ and with ${\delta }_{\mathrm{CP}}=-{90}^{\circ }$ is around ${14}^{\circ }$ $\left({7}^{\circ }\right)$ for the baseline option of 540 km (360 km). For hierarchy sensitivity, one can have $3\sigma $ sensitivity for 540 km baseline except ${\delta }_{\mathrm{CP}}=±{90}^{\circ }$ and $5\sigma $ sensitivity for 360 km baseline for all values of ${\delta }_{\mathrm{CP}}$ . The octant of ${\theta }_{23}$ can be determined at $3\sigma $ for the values of: ${\theta }_{23}>{51}^{\circ }$ ( ${\theta }_{23}<{42}^{\circ }$ and ${\theta }_{23}>{49}^{\circ }$ ) for baseline of 540 km (360 km). Regarding measurement precision of the atmospheric mixing parameters, the allowed values at $3\sigma $ are: ${40}^{\circ }<{\theta }_{23}<{52}^{\circ }$ ( ${42}^{\circ }<{\theta }_{23}<51.{5}^{\circ }$ ) and $2.485×{10}^{-3}$ eV ${}^{2}<\Delta {m}_{31}^{2}<2.545×{10}^{-3}$ eV ${}^{2}$ ( $2.49×{10}^{-3}$ eV ${}^{2}<\Delta {m}_{31}^{2}<2.54×{10}^{-3}$ eV ${}^{2}$ ) for the baseline of 540 km (360 km).
https://aperta.ulakbim.gov.trrecord/240172
oai:aperta.ulakbim.gov.tr:240172
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European Physical Journal C 81(12)
Updated physics performance of the ESSnuSB experiment
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:106009
2021-03-17T16:23:13Z
user-scoap3-turkiye
CERN İşbirliği
2019-01-01
A search for the rare radiative leptonic decay ${D}_{s}^{+}\to \gamma {e}^{+}{\nu }_{e}$ is performed for the first time using electron-positron collision data corresponding to an integrated luminosity of $3.19\text{}\text{}{\mathrm{fb}}^{-1}$, collected with the BESIII detector at a center-of-mass energy of 4.178 GeV. No evidence for the ${D}_{s}^{+}\to \gamma {e}^{+}{\nu }_{e}$ decay is seen, and an upper limit of $B\left({D}_{s}^{+}\to \gamma {e}^{+}{\nu }_{e}\right)<1.3×1{0}^{-4}$ is set on the partial branching fraction at a 90% confidence level for radiative photon energies ${E}_{\gamma }^{*}>0.01\text{}\text{}\mathrm{GeV}$.
https://aperta.ulakbim.gov.trrecord/106009
oai:zenodo.org:106009
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Physical Review D 99(7)
Search for the decay ${D}_{s}^{+}\to \gamma {e}^{+}{\nu }_{e}$
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:106591
2021-03-17T16:34:13Z
user-scoap3-turkiye
CERN İşbirliği
2018-01-01
A search for the exclusive decays of the Higgs and Z bosons to a ϕ or ρ meson and a photon is performed with a pp collision data sample corresponding to an integrated luminosity of up to 35.6 fb−1 collected at $\sqrt{s}=13$ TeV with the ATLAS detector at the CERN Large Hadron Collider. These decays have been suggested as a probe of the Higgs boson couplings to light quarks. No significant excess of events is observed above the background, as expected from the Standard Model. Upper limits at 95% confidence level were obtained on the branching fractions of the Higgs boson decays to ϕγ and ργ of 4.8 × 10−4 and 8.8 × 10−4, respectively. The corresponding 95% confidence level upper limits for the Z boson decays are 0.9 × 10−6 and 25 × 10−6 for ϕγ and ργ, respectively.
https://aperta.ulakbim.gov.trrecord/106591
oai:zenodo.org:106591
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Journal of High Energy Physics 2018(7)
Search for exclusive Higgs and Z boson decays to ϕγ and ργ with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:105759
2021-03-17T16:18:28Z
user-scoap3-turkiye
Mazharimousavi, S. Habib
Halilsoy, M.
2019-01-01
A non-singular magnetic black hole in nonlinear electrodynamics has been introduced recently whose Lagrangian contains an exponential factor [15]. We show that such regular black holes are available without resorting to a transcendental factor. A much simpler example of regular magnetic black hole solution is presented which admits the Schwarzschild limit as well as the unconditional unitarily condition.
https://aperta.ulakbim.gov.trrecord/105759
oai:zenodo.org:105759
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Physics Letters B 796 C
Note on regular magnetic black hole
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:36715
2021-03-17T16:29:54Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Mutuk, Halil
Sarac, Yasemin
Gumus, Hasan
Ozpineci, Altug
2018-01-01
X(3872) presents many surprises after its discovery more than ten years ago. Understanding its properties is crucial to understand the spectrum of possible exotic mesons. In this work, X(3872) meson and its heavy quark spin symmetry (HQSS) partners (including the mesons in the bottom sector) are studied within the QCD Sum Rules approach using a current motivated by the molecular picture of X(3872). We predict four heavy partners to X(3872) and bottomonium with the masses and J(PC) quantum numbers. Obtained results are in good agreement with the previous studies and available experimental data within errors.
https://aperta.ulakbim.gov.trrecord/36715
oai:zenodo.org:36715
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EUROPEAN PHYSICAL JOURNAL C 78(11)
X(3872) and its heavy quark spin symmetry partners in QCD sum rules
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:106769
2021-03-17T16:37:42Z
user-scoap3-turkiye
CERN İşbirliği
2018-01-01
This paper presents a measurement of the W boson production cross section and the W + /W − cross-section ratio, both in association with jets, in proton-proton collisions at $\sqrt{s}=8$ TeV with the ATLAS experiment at the Large Hadron Collider. The measurement is performed in final states containing one electron and missing transverse momentum using data corresponding to an integrated luminosity of 20.2 fb−1. Differential cross sections for events with at least one or two jets are presented for a range of observables, including jet transverse momenta and rapidities, the scalar sum of transverse momenta of the visible particles and the missing transverse momentum in the event, and the transverse momentum of the W boson. For a subset of the observables, the differential cross sections of positively and negatively charged W bosons are measured separately. In the cross-section ratio of W + /W − the dominant systematic uncertainties cancel out, improving the measurement precision by up to a factor of nine. The observables and ratios selected for this paper provide valuable input for the up quark, down quark, and gluon parton distribution functions of the proton.
https://aperta.ulakbim.gov.trrecord/106769
oai:zenodo.org:106769
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Journal of High Energy Physics 2018(5)
Measurement of differential cross sections and W + /W − cross-section ratios for W boson production in association with jets at $\sqrt{s}=8$ TeV with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:29035
2021-03-17T16:32:32Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Ambrogi, F.
Asilar, E.
Bergauer, T.
Brandstetter, J.
Brondolin, E.
Dragicevic, M.
Eroe, J.
Del Valle, A. Escalante
Flechl, M.
Fruehwirth, R.
Ghete, V. M.
Hrubec, J.
Jeitler, M.
Krammer, N.
Kraetschmer, I
Liko, D.
Madlener, T.
Madlener, T.
2018-01-01
Pseudorapidity, transverse momentum, and multiplicity distributions are measured in the pseudorapidity range vertical bar eta vertical bar < 2.4 for charged particles with transverse momenta satisfying pT > 0.5 GeV in proton-proton collisions at a center-of-mass energy of root s = 13 TeV. Measurements are presented in three different event categories. The most inclusive of the categories corresponds to an inelastic pp data set, while the other two categories are exclusive subsets of the inelastic sample that are either enhanced or depleted in single diffractive dissociation events. The measurements are compared to predictions from Monte Carlo event generators used to describe high-energy hadronic interactions in collider and cosmic-ray physics.
https://aperta.ulakbim.gov.trrecord/29035
oai:zenodo.org:29035
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EUROPEAN PHYSICAL JOURNAL C 78(9)
Measurement of charged particle spectra in minimum-bias events from proton-proton collisions at root s =13 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:57387
2021-03-17T16:54:39Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Azizi, K.
Bozkir, G.
2016-01-01
The thermal properties of the light decuplet baryons are investigated in the framework of the thermal QCD sum rules. In particular, the behavior of the mass and residue of the Delta, Sigma*, Xi*, and Omega baryons with respect to temperature are analyzed taking into account the additional operators appearing in the Wilson expansion at finite temperature. It is found that the mass and residue of these particles remain overall unaffected up to T similar or equal to 150 MeV but, beyond this point, they start to diminish considerably.
https://aperta.ulakbim.gov.trrecord/57387
oai:zenodo.org:57387
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EUROPEAN PHYSICAL JOURNAL C 76(10)
Decuplet baryons in a hot medium
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:106467
2021-03-17T16:31:53Z
user-scoap3-turkiye
CERN İşbirliği
2018-01-01
A search for supersymmetric partners of top quarks decaying as ${\stackrel{˜}{t}}_{1}\to c{\stackrel{˜}{\chi }}_{1}^{0}$ and supersymmetric partners of charm quarks decaying as ${\stackrel{˜}{c}}_{1}\to c{\stackrel{˜}{\chi }}_{1}^{0}$ , where ${\stackrel{˜}{\chi }}_{1}^{0}$ is the lightest neutralino, is presented. The search uses 36.1 fb−1 pp collision data at a centre-of-mass energy of 13 TeV collected by the ATLAS experiment at the Large Hadron Collider and is performed in final states with jets identified as containing charm hadrons. Assuming a 100% branching ratio to $c{\stackrel{˜}{\chi }}_{1}^{0}$ , top and charm squarks with masses up to 850 GeV are excluded at 95% confidence level for a massless lightest neutralino. For ${m}_{{\stackrel{˜}{t}}_{1},{\stackrel{˜}{c}}_{1}}-{m}_{{\stackrel{˜}{\chi }}_{1}^{0}}$ < 100 GeV, top and charm squark masses up to 500 GeV are excluded.
https://aperta.ulakbim.gov.trrecord/106467
oai:zenodo.org:106467
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Journal of High Energy Physics 2018(9)
Search for supersymmetry in final states with charm jets and missing transverse momentum in 13 TeV pp collisions with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:36483
2021-03-17T16:34:38Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Koksal, M.
Inan, S. C.
Billur, A. A.
Ozguven, Y.
Bahar, M. K.
2018-01-01
In this study, we investigate the potential of the process pp -> p gamma*p -> p tau(nu) over bar (tau)q' X at the LHC to examine the anomalous electromagnetic moments of the tau lepton. We obtain 95% confidence level bounds on the anomalous coupling parameters with various values of the integrated luminosity and center-of-mass energy. The improved bounds have been obtained on the anomalous coupling parameters of electric and magnetic moments of the tau lepton alpha(tau) and vertical bar d(tau)vertical bar compared to the current experimental sensitivity bounds. The gamma p mode of photon reactions at the LHC have shown that it has great potential for the electromagnetic dipole moments studies of the tau lepton. (C) 2018 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/). Funded by SCOAP(3).
https://aperta.ulakbim.gov.trrecord/36483
oai:zenodo.org:36483
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PHYSICS LETTERS B 783 375-380
Analysis of the anomalous electromagnetic moments of the tau lepton in gamma p collisions at the LHC
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:34017
2021-03-17T16:33:12Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Ambrogi, F.
Asilar, E.
Bergauer, T.
Brandstetter, J.
Brondolin, E.
Dragicevic, M.
Eroe, J.
Del Valle, A. Escalante
Flechl, M.
Friedl, M.
Fruehwirth, R.
Ghete, V. M.
Grossmann, J.
Hrubec, J.
Jeitler, M.
Koenig, A.
Krammer, N.
Krammer, N.
2018-01-01
Results of a search for the standard model Higgs boson produced in association with a top quark pair (t (t) over barH) in final states with electrons, muons, and hadronically decaying tau leptons are presented. The analyzed data set corresponds to an integrated luminosity of 35.9 fb(-1) recorded in proton-proton collisions at root s = 13 TeV by the CMS experiment in 2016. The sensitivity of the search is improved by using matrix element and machine learning methods to separate the signal from backgrounds. The measured signal rate amounts to 1.23(-0.43)(+0.45) times the production rate expected in the standard model, with an observed (expected) significance of 3.2 sigma (2.8 sigma), which represents evidence for t (t) over barH production in those final states. An upper limit on the signal rate of 2.1 times the standard model production rate is set at 95% confidence level.
https://aperta.ulakbim.gov.trrecord/34017
oai:zenodo.org:34017
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JOURNAL OF HIGH ENERGY PHYSICS 8
Evidence for associated production of a Higgs boson with a top quark pair in final states with electrons, muons, and hadronically decaying tau leptons at root s=13 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:4315
2021-03-17T16:02:49Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Ambrogi, F.
Bergauer, T.
Dragicevic, M.
Ero, J.
Del Valle, A. Escalante
Flechl, M.
Fruhwirth, R.
Jeitler, M.
Kratschmer, I
Liko, D.
Madlener, T.
Mikulec, I
Rad, N.
Schieck, J.
Schofbeck, R.
Spanring, M.
Waltenberger, W.
Waltenberger, W.
2020-01-01
A measurement of the W+W- boson pair production cross section in proton-proton collisions at root s = 13 TeV is presented. The data used in this study are collected with the CMS detector at the CERN LHC and correspond to an integrated luminosity of 35.9 fb(-1). The W+W- candidate events are selected by requiring two oppositely charged leptons (electrons or muons). Two methods for reducing background contributions are employed. In the first one, a sequence of requirements on kinematic quantities is applied allowing a measurement of the total production cross section, 117.6 +/- 6.8 pb, which agrees well with the theoretical prediction. Fiducial cross sections are also reported for events with zero or one jet, and the change in the zero-jet fiducial cross section with the jet transverse momentum threshold is measured. Normalized differential cross sections are reported within the fiducial region. A second method for suppressing background contributions employs two random forest classifiers. The analysis based on this method includes a measurement of the total production cross section and also a measurement of the normalized jet multiplicity distribution in W+W- events. Finally, a dilepton invariant mass distribution is used to probe for physics beyond the standard model in the context of an effective field theory, and constraints on the presence of dimension-6 operators are derived.
https://aperta.ulakbim.gov.trrecord/4315
oai:zenodo.org:4315
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PHYSICAL REVIEW D 102(9)
W+ W- boson pair production in proton-proton collisions at root s=13 TeV
info:eu-repo/semantics/article
publication-article
oai:aperta.ulakbim.gov.tr:240466
2022-10-07T16:47:36Z
user-scoap3-turkiye
Azizi, K.
Sarac, Y.
Sundu, H.
2021-01-01
We present an analysis of the newly observed pentaquark $P_c(4312)^+$ to shed light on its quantum numbers. To do that, the QCD sum rules approach is used. The measured mass of this particle is close to the $P_c(4312)^+$ threshold and has a small width, which supports the possibility of its being a molecular state. We consider an interpolating current in a molecular form and analyze both the positive and negative parity states with spin- $P_c(4312)^+$ . We also consider the bottom counterpart of the state with similar molecular form. Our mass result for the charm pentaquark state supports that the quantum numbers of the observed state are consistent with $P_c(4312)^+$ .
https://aperta.ulakbim.gov.trrecord/240466
oai:aperta.ulakbim.gov.tr:240466
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Chinese Physics C 45(5)
Properties of the (4312) Pentaquark and its Bottom Partner
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:106071
2021-03-17T16:24:20Z
user-scoap3-turkiye
CERN İşbirliği
2019-01-01
By analyzing $\left(448.1±2.9\right)×1{0}^{6}$ $\psi \left(3686\right)$ events collected with the BESIII detector operating at the BEPCII collider, the decays of ${\chi }_{cJ}\to 4{K}_{S}^{0}$ ($J=0$, 1, 2) are observed for the first time with statistical significances of $26.5\sigma $, $5.9\sigma $ and $11.4\sigma $, respectively. The product branching fractions of $\psi \left(3686\right)\to \gamma {\chi }_{cJ}$, ${\chi }_{cJ}\to 4{K}_{S}^{0}$ are presented, and the branching fractions of ${\chi }_{cJ}\to 4{K}_{S}^{0}$ decays are determined to be ${B}_{{\chi }_{c0}\to 4{K}_{S}^{0}}=\left(5.76±0.34±0.38\right)×1{0}^{-4}$, ${B}_{{\chi }_{c1}\to 4{K}_{S}^{0}}=\left(0.35±0.09±0.03\right)×1{0}^{-4}$ and ${B}_{{\chi }_{c2}\to 4{K}_{S}^{0}}=\left(1.14±0.15±0.08\right)×1{0}^{-4}$, where the first uncertainties are statistical and the second are systematic, respectively.
https://aperta.ulakbim.gov.trrecord/106071
oai:zenodo.org:106071
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Physical Review D 99(5)
Observation of ${\chi }_{cJ}\to 4{K}_{S}^{0}$
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:107659
2021-03-17T16:55:07Z
user-scoap3-turkiye
CERN İşbirliği
2016-01-01
The elliptic flow of electrons from heavy-flavour hadron decays at mid-rapidity (| y | < 0.7) is measured in Pb-Pb collisions at s N N = 2.76 TeV with ALICE at the LHC. The particle azimuthal distribution with respect to the reaction plane can be parametrized with a Fourier expansion, where the second coefficient ( v 2 ) represents the elliptic flow. The v 2 coefficient of inclusive electrons is measured in three centrality classes (0–10%, 10–20% and 20–40%) with the event plane and the scalar product methods in the transverse momentum ( p T ) intervals 0.5–13 GeV/ c and 0.5–8 GeV/ c , respectively. After subtracting the background, mainly from photon conversions and Dalitz decays of neutral mesons, a positive v 2 of electrons from heavy-flavour hadron decays is observed in all centrality classes, with a maximum significance of 5.9 σ in the interval 2 < p T < 2.5 GeV/ c in semi-central collisions (20–40%). The value of v 2 decreases towards more central collisions at low and intermediate p T (0.5 < p T < 3 GeV/ c ). The v 2 of electrons from heavy-flavour hadron decays at mid-rapidity is found to be similar to the one of muons from heavy-flavour hadron decays at forward rapidity (2.5 < y < 4). The results are described within uncertainties by model calculations including substantial elastic interactions of heavy quarks with an expanding strongly-interacting medium.
https://aperta.ulakbim.gov.trrecord/107659
oai:zenodo.org:107659
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Journal of High Energy Physics
Elliptic flow of electrons from heavy-flavour hadron decays at mid-rapidity in Pb-Pb collisions at s N N = 2.76 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:105889
2021-03-17T16:20:58Z
user-scoap3-turkiye
CERN İşbirliği
2019-01-01
Constraints on selected mediator-based dark matter models and a scalar dark energy model using up to 37 fb−1 $\sqrt{s}$ = 13 TeV pp collision data collected by the ATLAS detector at the LHC during 2015-2016 are summarised in this paper. The results of experimental searches in a variety of final states are interpreted in terms of a set of spin-1 and spin-0 single-mediator dark matter simplified models and a second set of models involving an extended Higgs sector plus an additional vector or pseudo-scalar mediator. The searches considered in this paper constrain spin-1 leptophobic and leptophilic mediators, spin-0 colour-neutral and colour-charged mediators and vector or pseudo-scalar mediators embedded in extended Higgs sector models. In this case, also $\sqrt{s}$ = 8 TeV pp collision data are used for the interpretation of the results. The results are also interpreted for the first time in terms of light scalar particles that could contribute to the accelerating expansion of the universe (dark energy).
https://aperta.ulakbim.gov.trrecord/105889
oai:zenodo.org:105889
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Journal of High Energy Physics 2019(5)
Constraints on mediator-based dark matter and scalar dark energy models using $\sqrt{s}$ = 13 TeV pp collision data collected by the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:107089
2021-03-17T16:43:50Z
user-scoap3-turkiye
CERN İşbirliği
2017-01-01
The cross section of a top-quark pair produced in association with a photon is measured in proton-proton collisions at a centre-of-mass energy of $\sqrt{s}=8$ TeV with 20.2 fb−1 of data collected by the ATLAS detector at the Large Hadron Collider in 2012. The measurement is performed by selecting events that contain a photon with transverse momentum p T > 15 GeV, an isolated lepton with large transverse momentum, large missing transverse momentum, and at least four jets, where at least one is identified as originating from a b-quark. The production cross section is measured in a fiducial region close to the selection requirements. It is found to be 139 ± 7 (stat.) ± 17 (syst.) fb, in good agreement with the theoretical prediction at next-to-leading order of 151 ± 24 fb. In addition, differential cross sections in the fiducial region are measured as a function of the transverse momentum and pseudorapidity of the photon.
https://aperta.ulakbim.gov.trrecord/107089
oai:zenodo.org:107089
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Journal of High Energy Physics 2017(11)
Measurement of the $t\overline{t}\gamma $ production cross section in proton-proton collisions at $\sqrt{s}=8$ TeV with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:106901
2021-03-17T16:40:06Z
user-scoap3-turkiye
CERN İşbirliği
2018-01-01
A search is conducted for new resonances decaying into a W W or W Z boson pair, where one W boson decays leptonically and the other W or Z boson decays hadronically. It is based on proton-proton collision data with an integrated luminosity of 36.1 fb−1 collected with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of $\sqrt{s}=13$ TeV in 2015 and 2016. The search is sensitive to diboson resonance production via vector-boson fusion as well as quark-antiquark annihilation and gluon-gluon fusion mechanisms. No significant excess of events is observed with respect to the Standard Model backgrounds. Several benchmark models are used to interpret the results. Limits on the production cross section are set for a new narrow scalar resonance, a new heavy vector-boson and a spin-2 Kaluza-Klein graviton.
https://aperta.ulakbim.gov.trrecord/106901
oai:zenodo.org:106901
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Journal of High Energy Physics 2018(3)
Search for W W/W Z resonance production in ℓνqq final states in pp collisions at $\sqrt{s}=13$ TeV with the ATLAS detector
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:105051
2021-03-17T16:04:39Z
user-scoap3-turkiye
CERN İşbirliği
2020-01-01
A search is conducted for a low-mass charged Higgs boson produced in a top quark decay and subsequently decaying into a charm and a strange quark. The data sample was recorded in proton-proton collisions at $\sqrt{s}=13\text{}\text{}\mathrm{TeV}$ by the CMS experiment at the LHC and corresponds to an integrated luminosity of $35.9\text{}\text{}{\mathrm{fb}}^{-1}$. The search is performed in the process of top quark pair production, where one top quark decays to a bottom quark and a charged Higgs boson and the other to a bottom quark and a $W$ boson. With the $W$ boson decaying to a charged lepton (electron or muon) and a neutrino, the final state comprises an isolated lepton, missing transverse momentum, and at least four jets, of which two are tagged as $b$ jets. To enhance the search sensitivity, one of the jets originating from the charged Higgs boson is required to satisfy a charm tagging selection. No significant excess beyond standard model predictions is found in the dijet invariant mass distribution. An upper limit in the range 1.68%–0.25% is set on the branching fraction of the top quark decay to the charged Higgs boson and bottom quark for a charged Higgs boson mass between 80 and 160 GeV.
https://aperta.ulakbim.gov.trrecord/105051
oai:zenodo.org:105051
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Physical Review D 102(7)
Search for a light charged Higgs boson in the ${H}^{±}\to cs$ channel in proton-proton collisions at $\sqrt{s}=13\text{}\text{}\mathrm{TeV}$
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:72693
2021-03-17T16:26:33Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Ambrogi, F.
Asilar, E.
Bergauer, T.
Brandstetter, J.
Brondolin, E.
Dragicevic, M.
Eroe, J.
Del Valle, A. Escalante
Flechl, M.
Friedl, M.
Fruehwirth, R.
Ghete, V. M.
Grossmann, J.
Hrubec, J.
Jeitler, M.
Koenig, A.
Krammer, N.
Krammer, N.
2019-01-01
The cross sections for gamma(1S), gamma(2S), and gamma(3S) production in lead-lead (PbPb) and proton-proton (pp) collisions at root s(NN) = 5.02 TeV have been measured using the CMS detector at the LHC. The nuclear modification factors, R-AA, derived from the PbPb-to-pp ratio of yields for each state, are studied as functions of meson rapidity and transverse momentum, as well as PbPb collision centrality. The yields of all three states are found to be significantly suppressed, and compatible with a sequential ordering of the suppression, R-AA(T(1S)) > R-AA(gamma(2S)) > R-AA(gamma(3S)). The suppression of gamma(1S) is larger than that seen at root s(NN) = 2.76 TeV, although the two are compatible within uncertainties. The upper limit on the R-AA of gamma(3S) integrated over p(T), rapidity and centrality is 0.096 at 95% confidence level, which is the strongest suppression observed for a quarkonium state in heavy ion collisions to date. (C) 2019 The Author(s). Published by Elsevier B.V.
https://aperta.ulakbim.gov.trrecord/72693
oai:zenodo.org:72693
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PHYSICS LETTERS B 790 270-293
Measurement of nuclear modification factors of gamma(1S)), gamma(2S), and gamma(3S) mesons in PbPb collisions at root s(NN)=5.02 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:4325
2021-03-17T16:01:54Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Ambrogi, F.
Bergauer, T.
Dragicevic, M.
Ero, J.
Del Valle, A. Escalante
Flechl, M.
Fruhwirth, R.
Jeitler, M.
Kratschmer, I
Liko, D.
Madlener, T.
Mikulec, I
Rad, N.
Schieck, J.
Schofbeck, R.
Spanring, M.
Waltenberger, W.
Waltenberger, W.
2020-01-01
A search is described for the production of a pair of bottom-type vectorlike quarks (VLQs), each decaying into a b or (b) over bar quark and either a Higgs or a Z boson, with a mass greater than 1000 GeV. The analysis is based on data from proton-proton collisions at a 13 TeV center-of-mass energy recorded at the CERN LHC, corresponding to a total integrated luminosity of 137 fb(-1). As the predominant decay modes of the Higgs and Z bosons are to a pair of quarks, the analysis focuses on final states consisting of jets resulting from the six quarks produced in the events. Since the two jets produced in the decay of a highly Lorentz-boosted Higgs or Z boson can merge to form a single jet, nine independent analyses are performed, categorized by the number of observed jets and the reconstructed event mode. No signal in excess of the expected background is observed. Lower limits are set on the VLQ mass at 95% confidence level equal to 1570 GeV in the case where the VLQ decays exclusively to a b quark and a Higgs boson, 1390 GeV for when it decays exclusively to a b quark and a Z boson, and 1450 GeV for when it decays equally in these two modes. These limits represent significant improvements over the previously published VLQ limits.
https://aperta.ulakbim.gov.trrecord/4325
oai:zenodo.org:4325
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PHYSICAL REVIEW D 102(11)
Search for bottom-type, vectorlike quark pair production in a fully hadronic final state in proton-proton collisions at root s=13 TeV
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:69451
2021-03-17T16:13:37Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Gurses, Metin
Heydarzade, Yaghoub
Senturk, Cetin
2019-01-01
We study some physical properties of black holes in Null Aether Theory (NAT) - a vector-tensor theory of gravity. We first review the black hole solutions in NAT and then derive the first law of black hole thermodynamics. The temperature of the black holes depends on both the mass and the NAT "charge" of the black holes. The extreme cases where the temperature vanishes resemble the extreme Reissner-Nordstrom black holes. We also discuss the contribution of the NAT charge to the geodesics of massive and massless particles around the NAT black holes.
https://aperta.ulakbim.gov.trrecord/69451
oai:zenodo.org:69451
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EUROPEAN PHYSICAL JOURNAL C 79(11)
NAT black holes
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publication-article
oai:aperta.ulakbim.gov.tr:240248
2022-10-07T15:29:51Z
user-scoap3-turkiye
CERN İşbirliği
2021-01-01
Searches for new resonances in the diphoton final state, with spin 0 as predicted by theories with an extended Higgs sector and with spin 2 using a warped extra-dimension benchmark model, are presented using 139 fb$^{−1}$ of $\sqrt{s}=13$ TeV pp collision data collected by the ATLAS experiment at the LHC. No significant deviation from the Standard Model is observed and upper limits are placed on the production cross-section times branching ratio to two photons as a function of the resonance mass.
https://aperta.ulakbim.gov.trrecord/240248
oai:aperta.ulakbim.gov.tr:240248
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Physics Letters B 822 C
Search for resonances decaying into photon pairs in 139 fb Of Collisions at TeV with the ATLAS detector
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publication-article
oai:zenodo.org:106433
2021-03-17T16:31:15Z
user-scoap3-turkiye
CERN İşbirliği
2018-01-01
Charged Higgs bosons produced either in top-quark decays or in association with a top-quark, subsequently decaying via H ± → τ ± ν τ , are searched for in 36.1 fb−1 of proton-proton collision data at $\sqrt{s}=13$ TeV recorded with the ATLAS detector. Depending on whether the top-quark produced together with H ± decays hadronically or leptonically, the search targets τ+jets and τ+lepton final states, in both cases with a hadronically decaying τ-lepton. No evidence of a charged Higgs boson is found. For the mass range of ${m}_{{H}^{±}}$ = 90–2000 GeV, upper limits at the 95% confidence level are set on the production cross-section of the charged Higgs boson times the branching fraction $ℬ\left({H}^{±}\to {\tau }^{±}{\nu }_{\tau }\right)$ in the range 4.2–0.0025 pb. In the mass range 90–160 GeV, assuming the Standard Model cross-section for $t\overline{t}$ production, this corresponds to upper limits between 0.25% and 0.031% for the branching fraction $ℬ\left(t\to b{H}^{±}\right)×ℬ\left({H}^{±}\to {\tau }^{±}{\nu }_{\tau }\right)$ .
https://aperta.ulakbim.gov.trrecord/106433
oai:zenodo.org:106433
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Journal of High Energy Physics 2018(9)
Search for charged Higgs bosons decaying via H ± → τ ± ν τ in the τ+jets and τ+lepton final states with 36 fb−1 of pp collision data recorded at $\sqrt{s}=13$ TeV with the ATLAS experiment
info:eu-repo/semantics/article
publication-article
oai:zenodo.org:54429
2021-03-17T16:55:58Z
user-tubitak-destekli-proje-yayinlari
user-scoap3-turkiye
Khachatryan, V.
Sirunyan, A. M.
Tumasyan, A.
Adam, W.
Asilar, E.
Bergauer, T.
Brandstetter, J.
Brondolin, E.
Dragicevic, M.
Eroe, J.
Flechl, M.
Friedl, M.
Fruehwirth, R.
Ghete, V. M.
Hartl, C.
Hoermann, N.
Hrubec, J.
Jeitler, M.
Koenig, A.
Krammer, M.
Krammer, M.
2016-01-01
The inclusive cross section for top quark pair production is measured in proton-proton collisions at root s = 7 and 8TeV, corresponding to 5.0 and 19.7 fb(-1), respectively, with the CMS experiment at the LHC. The cross sections are measured in the electron-muon channel using a binned likelihood fit to multi-differential final state distributions related to identified b quark jets and other jets in the event. The measured cross section values are 173.6 +/- 2.1 (stat)(-4.0)(+ 4.5)(syst) +/- 3.8 (lumi) pb at root s = 7TeV, and 244.9 +/- 1.4(stat)(-5.5)(+6.3) (syst) +/- 6.4 (lumi) pb at root s = 8TeV, in good agreement with QCD calculations at next-to-nextto- leading-order accuracy. The ratio of the cross sections measured at 7 and 8TeV is determined, as well as cross sections in the fiducial regions defined by the acceptance requirements on the two charged leptons in the final state. The cross section results are used to determine the top quark pole mass via the dependence of the theoretically predicted cross section on the mass, giving a best result of 173.8(-1.8)(+1.7) GeV. The data at root s = 8TeV are also used to set limits, for two neutralino mass values, on the pair production of supersymmetric partners of the top quark with masses close to the top quark mass.
https://aperta.ulakbim.gov.trrecord/54429
oai:zenodo.org:54429
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JOURNAL OF HIGH ENERGY PHYSICS 8
Measurement of the t(t)over-bar production cross section in the e mu channel in proton-proton collisions at root s=7 and 8 TeV
info:eu-repo/semantics/article
publication-article
oai:aperta.ulakbim.gov.tr:240232
2022-10-07T15:29:12Z
user-scoap3-turkiye
CERN İşbirliği
2021-01-01
This Letter reports results from the first long-baseline search for sterile antineutrinos mixing in an accelerator-based antineutrino-dominated beam. The rate of neutral-current interactions in the two NOvA detectors, at distances of 1 and 810 km from the beam source, is analyzed using an exposure of $12.51×{10}^{20}$ protons-on-target from the NuMI beam at Fermilab running in antineutrino mode. A total of 121 of neutral-current candidates are observed at the far detector, compared to a prediction of $122±11\left(\mathrm{stat}.\right)±15\left(\mathrm{syst}.\right)$ assuming mixing only between three active flavors. No evidence for ${\overline{\nu }}_{\mu }\to {\overline{\nu }}_{s}$ oscillation is observed. Interpreting this result within a $3+1$ model, constraints are placed on the mixing angles ${\theta }_{24}<25°$ and ${\theta }_{34}<32°$ at the 90% C.L. for $0.05\text{}\text{}{\mathrm{eV}}^{2}\le \Delta {m}_{41}^{2}\le 0.5\text{}\text{}{\mathrm{eV}}^{2}$, the range of mass splittings that produces no significant oscillations at the near detector. These are the first $3+1$ confidence limits set using long-baseline accelerator antineutrinos.
https://aperta.ulakbim.gov.trrecord/240232
oai:aperta.ulakbim.gov.tr:240232
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Physical Review Letters 127(20)
Search for Active-Sterile Antineutrino Mixing Using Neutral-Current Interactions with the NOvA Experiment
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publication-article
oai:zenodo.org:106741
2021-03-17T16:37:09Z
user-scoap3-turkiye
CERN İşbirliği
2018-01-01
A direct search for the standard model Higgs boson decaying to a pair of charm quarks is presented. Associated production of the Higgs and $Z$ bosons, in the decay mode $ZH\to {\ell }^{+}{\ell }^{-}c\overline{c}$ is studied. A data set with an integrated luminosity of $36.1\text{}\text{}{\mathrm{fb}}^{-1}$ of $pp$ collisions at $\sqrt{s}=13\mathrm{TeV}$ recorded by the ATLAS experiment at the LHC is used. The $H\to c\overline{c}$ signature is identified using charm-tagging algorithms. The observed (expected) upper limit on $\sigma \left(pp\to ZH\right)×B\left(H\to c\overline{c}\right)$ is 2.7 (${3.9}_{-1.1}^{+2.1}$) pb at the 95% confidence level for a Higgs boson mass of 125 GeV, while the standard model value is 26 fb.
https://aperta.ulakbim.gov.trrecord/106741
oai:zenodo.org:106741
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Physical Review Letters 120(21)
Search for the Decay of the Higgs Boson to Charm Quarks with the ATLAS Experiment
info:eu-repo/semantics/article
publication-article
oai:aperta.ulakbim.gov.tr:262641
2023-07-29T19:09:08Z
user-scoap3-turkiye
CERN İşbirliği
2022-01-01
Using inclusive decays of $J/\psi $ , a precise determination of the number of $J/\psi $ events collected with the BESIII detector was performed. For the two data sets taken in 2009 and 2012, the numbers of $J/\psi $ events were recalculated to be $J/\psi $ and $J/\psi $ , respectively; these numbers are in good agreement with the previous measurements. For the $J/\psi $ sample taken in 2017–2019, the number of events was determined to be $J/\psi $ . The total number of $J/\psi $ events collected with the BESIII detector was determined to be $J/\psi $ , where the uncertainty is dominated by systematic effects, and the statistical uncertainty is negligible.
https://aperta.ulakbim.gov.trrecord/262641
oai:aperta.ulakbim.gov.tr:262641
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Chinese Physics C 46(7)
Number of events at BESIII
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publication-article
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