@article{OPUS4-22684,
  title     = {Search for high-mass dilepton resonances using 139 fb\(^{-1}\) of \(pp\) collision data collected at root \(s\)=13 TeV with the ATLAS detector},
  series = {Physics Letters B},
  volume    = {796},
  journal   = {Physics Letters B},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2019.07.016},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226844},
  pages     = {68-87},
  year      = {2019},
  abstract  = {A search for high-mass dielectron and dimuon resonances in the mass range of 250 GeV to 6TeV is presented. The data were recorded by the ATLAS experiment in proton-proton collisions at a centre-ofmass energy of root s = 13 TeV during Run 2 of the Large Hadron Collider and correspond to an integrated luminosity of 139 fb(-1). A functional form is fitted to the dilepton invariant-mass distribution to model the contribution from background processes, and a generic signal shape is used to determine the significance of observed deviations from this background estimate. No significant deviation is observed and upper limits are placed at the 95\% confidence level on the fiducial cross-section times branching ratio for various resonance width hypotheses. The derived limits are shown to be applicable to spin-0, spin-1 and spin-2 signal hypotheses. For a set of benchmark models, the limits are converted into lower limits on the resonance mass and reach 4.5 TeV for the E-6-motivated Z(psi)' boson. Also presented are limits on Heavy Vector Triplet model couplings. (C) 2019 The Author. Published by Elsevier B.V.},
  language  = {en}
}
@article{OPUS4-22683,
  title     = {Search for a heavy charged boson in events with a charged lepton and missing transverse momentum from \(pp\) collisions at √\(s\)=13 TeV with the ATLAS detector},
  series = {Physical Review D},
  volume    = {100},
  journal   = {Physical Review D},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1103/PhysRevD.100.052013},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226835},
  pages     = {1-29},
  year      = {2019},
  abstract  = {A search for a heavy charged-boson resonance decaying into a charged lepton (electron or muon) and a neutrino is reported. A data sample of 139 fb(-1) of proton-proton collisions at root s = 13 TeV collected with the ATLAS detector at the LHC during 2015-2018 is used in the search. The observed transverse mass distribution computed from the lepton and missing transverse momenta is consistent with the distribution expected from the Standard Model, and upper limits on the cross section for pp -> W'-> lv are extracted (l = e or mu). These vary between 1.3 pb and 0.05 tb depending on the resonance mass in the range between 0.15 and 7.0 TeV at 95\% confidence level for the electron and muon channels combined. Gauge bosons with a mass below 6.0 and 5.1 TeV are excluded in the electron and muon channels, respectively, in a model with a resonance that has couplings to fermions identical to those of the Standard Model W boson. Cross-section limits are also provided for resonances with several fixed Gamma/m values in the range between 1\% and 15\%. Model-independent limits are derived in single-bin signal regions defined by a varying minimum transverse mass threshold. The resulting visible cross-section upper limits range between 4.6 (15) ph and 22 (22) ab as the threshold increases from 130 (110) GeV to 5.1 (5.1) TeV in the electron (muon) channel.},
  language  = {en}
}
@article{OPUS4-22685,
  title     = {Measurement of the cross-section and charge asymmetry of W bosons produced in proton-proton collisions at √\(s\)=8 TeV with the ATLAS detector},
  series = {European Physical Journal C},
  volume    = {79},
  journal   = {European Physical Journal C},
  number    = {760},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-019-7199-0},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226850},
  pages     = {1-25},
  year      = {2019},
  abstract  = {This paper presents measurements of the W+->mu+nu and W-->mu-nu cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton-proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2fb(-1). The precision of the cross-section measurements varies between 0.8 and 1.5\% as a function of the pseudorapidity, excluding the 1.9\% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.},
  language  = {en}
}
@article{OPUS4-22656,
  title     = {Evidence for the associated production of the Higgs boson and a top quark pair with the ATLAS detector},
  series = {Physical Review D},
  volume    = {97},
  journal   = {Physical Review D},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1103/PhysRevD.97.072003},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226569},
  pages     = {1-44},
  year      = {2018},
  abstract  = {A search for the associated production of the Higgs boson with a top quark pair (tt (b) over barH) is reported. The search is performed in multilepton final states using a data set corresponding to an integrated luminosity of 36.1 fb(-1) of proton-proton collision data recorded by the ATLAS experiment at a center-of-mass energy root s = 13 TeV at the Large Hadron Collider. Higgs boson decays to WW*, tau tau, and ZZ* are targeted. Seven final states, categorized by the number and flavor of charged-lepton candidates, are examined for the presence of the Standard Model Higgs boson with a mass of 125 GeVand a pair of top quarks. An excess of events over the expected background from Standard Model processes is found with an observed significance of 4.1 standard deviations, compared to an expectation of 2.8 standard deviations. The best fit for the (tt (b) over barH) production cross section is sot (tt (b) over barH) = 790(-210)(+230) fb, in agreement with the Standard Model prediction of 507(-50)(+35) fb. The combination of this result with other tt (b) over barH searches from the ATLAS experiment using the Higgs boson decay modes to b (b) over bar, gamma gamma and ZZ* -> 4l, has an observed significance of 4.2 standard deviations, compared to an expectation of 3.8 standard deviations. This provides evidence for the tt (b) over barH production mode.},
  language  = {en}
}
@article{OPUS4-22605,
  title     = {Prompt and non-prompt \(J\)/\(ψ\) and \(ψ\)(2S) suppression at high transverse momentum in 5.02 TeV Pb+Pb collisions with the ATLAS experiment},
  series = {European Physical Journal C},
  volume    = {78},
  journal   = {European Physical Journal C},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-018-6219-9},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226056},
  pages     = {1-28},
  year      = {2018},
  abstract  = {A measurement of J/psi and psi(2S) production is presented. It is based on a data sample from Pb+Pb collisions at root s(NN) = 5.02 TeV and pp collisions at root s = 5.02 TeV recorded by the ATLAS detector at the LHC in 2015, corresponding to an integrated luminosity of 0.42 nb(-1) and 25 pb(-1) in Pb+Pb and pp, respectively. The measurements of per-event yields, nuclear modification factors, and non-prompt fractions are performed in the dimuon decay channel for 9 < p(T)(mu mu) < 40 GeV in dimuon transverse momentum, and -2 < y(mu mu) < 2 in rapidity. Strong suppression is found in Pb+Pb collisions for both prompt and non-prompt J/psi, increasing with event centrality. The suppression of prompt psi(2S) is observed to be stronger than that of J/psi, while the suppression of non-prompt psi(2S) is equal to that of the non-prompt J/psi within uncertainties, consistent with the expectation that both arise from b-quarks propagating through the medium. Despite prompt and non-prompt J/psi arising from different mechanisms, the dependence of their nuclear modification factors on centrality is found to be quite similar.},
  language  = {en}
}
@article{OPUS4-22679,
  title     = {Measurement of τ polarisation in \(Z/\)γ* -> τ τ decays in proton-proton collisions at root \(s\)=8 TeV with the ATLAS detector},
  series = {European Physical Journal C},
  volume    = {78},
  journal   = {European Physical Journal C},
  number    = {163},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-018-5619-1},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226794},
  pages     = {1-30},
  year      = {2018},
  abstract  = {This paper presents a measurement of the polarisation of tau leptons produced in Z/gamma* -> tau tau decays which is performed with a dataset of proton-proton collisions at root s = 8 TeV, corresponding to an integrated luminosity of 20.2 fb(-1) recorded with the ATLAS detector at the LHC in 2012. The Z/gamma* -> tau tau decays are reconstructed from a hadronically decaying tau lepton with a single charged particle in the final state, accompanied by a tau lepton that decays leptonically. The tau polarisation is inferred from the relative fraction of energy carried by charged and neutral hadrons in the hadronic tau decays. The polarisation is measured in a fiducial region that corresponds to the kinematic region accessible to this analysis. The tau polarisation extracted over the full phase space within the Z/gamma* mass range of 66 < mZ/gamma* < 116GeVis found to be P-tau = -0.14 +/- 0.02(stat)+/- 0.04(syst). It is in agreement with the Standard Model prediction of Pt = -0.1517 +/- 0.0019, which is obtained from the ALP-GEN event generator interfaced with the PYTHIA 6 parton shower modelling and the TAUOLA tau decay library.},
  language  = {en}
}