@article{OPUS4-22602,
  title     = {Measurements of differential cross sections of top quark pair production in association with jets in pp collisions at root s=13 TeV using the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {159},
  journal   = {Journal of High Energy Physics},
  number    = {10},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1007/JHEP10(2018)159},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-226023},
  pages     = {1-57},
  year      = {2018},
  abstract  = {Measurements of di ff erential cross sections of top quark pair production in association with jets by the ATLAS experiment at the LHC are presented. The measurements are performed as functions of the top quark transverse momentum, the transverse momentum of the top quark-antitop quark system and the out-of-plane transverse momentum using data from pp collisions at p s = 13TeV collected by the ATLAS detector at the LHC in 2015 and corresponding to an integrated luminosity of 3.2 fb. The top quark pair events are selected in the lepton (electron or muon) + jets channel. The measured cross sections, which are compared to several predictions, allow a detailed study of top quark production.},
  language  = {en}
}
@article{OPUS4-17335,
  title     = {Measurement of the inclusive cross-sections of single top-quark and top-antiquark \(t\)-channel production in \(pp\) collisions at \(\sqrt{s}\) = 13 TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {2017},
  journal   = {Journal of High Energy Physics},
  number    = {04},
  organization    = {The ATLAS Collaboration},
  doi       = {https://doi.org/10.1007/JHEP04(2017)086},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-173357},
  year      = {2017},
  abstract  = {A measurement of the \(t\)-channel single-top-quark and single-top-antiquark production cross-sections in the lepton+jets channel is presented, using 3.2 fb\(^{-1}\) of proton-proton collision data at a centre-of-mass energy of 13 TeV, recorded with the ATLAS detector at the LHC in 2015. Events are selected by requiring one charged lepton (electron or muon), missing transverse momentum, and two jets with high transverse momentum, exactly one of which is required to be \(b\)-tagged. Using a binned maximum-likelihood fit to the discriminant distribution of a neural network, the cross-sections are determined to be \({σ(tq)}\) = 156 ± 5 (stat.) ± 27 (syst.) ± 3 (lumi.) pb for single top-quark production and \(σ(\overline{t}q)\) = 91 ± 4 (stat.) ± 18 (syst.) ± 2 (lumi.) pb for single top-antiquark production, assuming a top-quark mass of 172.5 GeV. The cross-section ratio is measured to be \(R_{t}\) = \(σ(tq)/σ(\overline{t}q)\) = 1.72 ± 0.09 (stat.) ± 0.18 (syst.). All results are in agreement with Standard Model predictions.},
  language  = {en}
}
@article{OPUS4-17220,
  title     = {Measurement of the Drell-Yan triple-differential cross section in \(pp\) collisions at \(\sqrt{s}\) = 8 TeV},
  series = {Journal of High Energy Physics},
  volume    = {59},
  journal   = {Journal of High Energy Physics},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1007/JHEP12(2017)059},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-172204},
  year      = {2017},
  abstract  = {This paper presents a measurement of the triple-differential cross section for the Drell-Yan process \({Z/γ^*}\) → ℓ\(^+\)ℓ\(^-\) where ℓ is an electron or a muon. The measurement is performed for invariant masses of the lepton pairs, \(m_{ℓℓ}\) , between 46 and 200 GeV using a sample of 20.2 fb\(^{-1}\) of \(pp\) collisions data at a centre-of-mass energy of \(\sqrt{s}\) = 8 TeV collected by the ATLAS detector at the LHC in 2012. The data are presented in bins of invariant mass, absolute dilepton rapidity, |\(y_{ℓℓ}\)|, and the angular variable cos \(θ^*\) between the outgoing lepton and the incoming quark in the Collins-Soper frame. The measurements are performed in the range |\(y_{ℓℓ}\)| < 2.4 in the muon channel, and extended to |\(y_{ℓℓ}\)| < 3.6 in the electron channel. The cross sections are used to determine the \(Z\) boson forward-backward asymmetry as a function of |\(y_{ℓℓ}\)| and \(m_{ℓℓ}\) . The measurements achieve high-precision, below the percent level in the pole region, excluding the uncertainty in the integrated luminosity, and are in agreement with predictions. These precision data are sensitive to the parton distribution functions and the effective weak mixing angle.},
  language  = {en}
}
@article{OPUS4-17239,
  title     = {Measurement of the \(t\overline{t}γ\) production cross section in proton-proton collisions at \(\sqrt{s} = 8\) TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {2017},
  journal   = {Journal of High Energy Physics},
  number    = {86},
  organization    = {The ATLAS Collaboration},
  doi       = {https://doi.org/10.1007/JHEP11(2017)086},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-172399},
  year      = {2017},
  abstract  = {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.},
  language  = {en}
}
@article{OPUS4-22085,
  title     = {Measurement of inclusive jet and dijet cross-sections in proton-proton collisions at root s=13 TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {195},
  journal   = {Journal of High Energy Physics},
  number    = {5},
  organization    = {The ATLAS collaboration},
  doi       = {10.1007/JHEP05(2018)195},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220853},
  pages     = {1-48},
  year      = {2018},
  abstract  = {Inclusive jet and dijet cross-sections are measured in proton-proton collisions at a centre-of-mass energy of 13 TeV. The measurement uses a dataset with an integrated luminosity of 3.2 fb(-1) recorded in 2015 with the ATLAS detector at the Large Hadron Collider. Jets are identified using the anti-lit algorithm with a radius parameter value of R = 0.4. The inclusive jet cross-sections are measured double-differentially as a function of the jet transverse momentum, covering the range from 100 GeV to 3.5 TeV, and the absolute jet rapidity up to vertical bar y vertical bar = 3. The double-differential dijet production cross-sections are presented as a function of the dijet mass, covering the range from 300 GeV to 9 TeV, and the half absolute rapidity separation between the two leading jets within vertical bar y vertical bar < 3, y*, up to y* = 3. Next-to-leading-order, and next-to-next-to-leading-order for the inclusive jet measurement, perturbative QCD calculations corrected for non-perturbative and electroweak effects are compared to the measured cross-sections.},
  language  = {en}
}
@article{OPUS4-22087,
  title     = {Measurement of differential cross sections and W\(^+\)/W\(^-\) cross-section ratios for W boson production in association with jets at root s=8 TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {77},
  journal   = {Journal of High Energy Physics},
  number    = {5},
  organization    = {The ATLAS collaboration},
  doi       = {10.1007/JHEP05(2018)077},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220872},
  pages     = {1-61},
  year      = {2018},
  abstract  = {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 root 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.},
  language  = {en}
}
@article{OPUS4-17336,
  title     = {Measurement of charged-particle distributions sensitive to the underlying event in \(\sqrt{s}\) = 13 TeV proton-proton collisions with the ATLAS detector at the LHC},
  series = {Journal of High Energy Physics},
  volume    = {2017},
  journal   = {Journal of High Energy Physics},
  number    = {03},
  organization    = {The ATLAS Collaboration},
  doi       = {https://doi.org/10.1007/JHEP03(2017)157},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-173361},
  year      = {2017},
  abstract  = {We present charged-particle distributions sensitive to the underlying event, measured by the ATLAS detector in proton-proton collisions at a centre-of-mass energy of 13 TeV, in low-luminosity Large Hadron Collider fills corresponding to an integrated luminosity of 1.6 nb\(^{-1}\). The distributions were constructed using charged particles with absolute pseudorapidity less than 2.5 and with transverse momentum greater than 500 MeV, in events with at least one such charged particle with transverse momentum above 1 GeV. These distributions characterise the angular distribution of energy and particle flows with respect to the charged particle with highest transverse momentum, as a function of both that momentum and of charged-particle multiplicity. The results have been corrected for detector effects and are compared to the predictions of various Monte Carlo event generators, experimentally establishing the level of underlying-event activity at LHC Run 2 energies and providing inputs for the development of event generator modelling. The current models in use for UE modelling typically describe this data to 5\% accuracy, compared with data uncertainties of less than 1\%.},
  language  = {en}
}
@article{OPUS4-22067,
  title     = {Angular analysis of B-d(0) -> K* µ\(^+\)μ\(^-\) decays in \({pp}\) collisions at root s=8 TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {47},
  journal   = {Journal of High Energy Physics},
  organization    = {The ATLAS collaboration},
  doi       = {10.1007/JHEP10(2018)047},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220670},
  pages     = {1-47},
  year      = {2018},
  abstract  = {An angular analysis of the decay B-d(0) -> K*mu(+)mu(-) is presented, based on proton-proton collision data recorded by the ATLAS experiment at the LHC. The study is using 20.3 fb(-1) of integrated luminosity collected during 2012 at centre-of-mass energy of root s = 8TeV. Measurements of the K* longitudinal polarisation fraction and a set of angular parameters obtained for this decay are presented. The results are compatible with the Standard Model predictions.},
  language  = {en}
}
@article{OPUS4-17231,
  title     = {Analysis of the Wtb vertex from the measurement of triple-differential angular decay rates of single top quarks produced in the \(t\)-channel at \(\sqrt{s}\) = 8 TeV with the ATLAS detector},
  series = {Journal or High Energy Physics},
  volume    = {2017},
  journal   = {Journal or High Energy Physics},
  number    = {17},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1007/JHEP12(2017)017},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-172310},
  year      = {2017},
  abstract  = {The electroweak production and subsequent decay of single top quarks in the \(t\)-channel is determined by the properties of the \({Wtb}\) vertex, which can be described by the complex parameters of an effective Lagrangian. An analysis of a triple-differential decay rate in \(t\)-channel production is used to simultaneously determine five generalised helicity fractions and phases, as well as the polarisation of the produced top quark. The complex parameters are then constrained. This analysis is based on 20.2 fb\(^{-1}\) of proton-proton collision data at a centre-of-mass energy of 8 TeV collected with the ATLAS detector at the LHC. The fraction of decays containing transversely polarised \(W\) bosons is measured to be \(f_1\) = 0.30 ± 0.05. The phase between amplitudes for transversely and longitudinally polarised \(W\) bosons recoiling against left-handed \(b\)-quarks is measured to be \(\delta\)_ = 0.002\(\pi^{+0.016\pi}_{+0.017\pi}\), giving no indication of CP violation. The fractions of longitudinal or transverse \(W\) bosons accompanied by right-handed \(b\)-quarks are also constrained. Based on these measurements, limits are placed at 95\% CL on the ratio of the complex coupling parameters Re [\({g_R/V_L}\) \(\in\) [-0.12, 0.17] and Im [\({g_R/V_L}\) \(\in\) [-0.07, 0.06]. Constraints are also placed on the ratios |\({V_R}/{V_L}\)| and |\({g_L}/{V_L}\)|. In addition, the polarisation of single top quarks in the \(t\)-channel is constrained to be \(P\) > 0.72 (95\% CL). None of the above measurements make assumptions about the value of any of the other parameters or couplings and all of them are in agreement with the Standard Model.},
  language  = {en}
}