@article{OPUS4-12751,
  title     = {Search for a heavy top-quark partner in final states with two leptons with the ATLAS detector at the LHC},
  series = {Journal of High Energy Physics},
  volume    = {11},
  journal   = {Journal of High Energy Physics},
  number    = {094},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP11(2012)094},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127511},
  year      = {2012},
  abstract  = {The results of a search for direct pair production of heavy top-quark partners in 4.7 fb\(^{-1}\) of integrated luminosity from pp collisions at √s=7 TeV collected by the ATLAS detector at the LHC are reported. Heavy top-quark partners decaying into a top quark and a neutral non-interacting particle are searched for in events with two leptons in the final state. No excess above the Standard Model expectation is observed. Limits are placed on the mass of a supersymmetric scalar top and of a spin-1/2 top-quark partner. A spin-1/2 top-quark partner with a mass between 300 GeV and 480 GeV, decaying to a top quark and a neutral non-interacting particle lighter than 100 GeV, is excluded at 95\% confidence level.},
  language  = {en}
}
@article{OPUS4-12752,
  title     = {Search for top and bottom squarks from gluino pair production in final states with missing transverse energy and at least three b-jets with the ATLAS detector},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {2174},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2174-z},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127523},
  year      = {2012},
  abstract  = {This letter reports the results of a search for top and bottom squarks from gluino pair production in 4.7 fb\(^{-1}\) of pp collisions at √s=7 TeV using the ATLAS detector at the LHC. The search is performed in events with large missing transverse momentum and at least three jets identified as originating from a b-quark. Exclusion limits are presented for a variety of gluino-mediated models with gluino masses up to 1 TeV excluded.},
  language  = {en}
}
@article{OPUS4-12753,
  title     = {Performance of missing transverse momentum reconstruction in proton-proton collisions at √s=7 TeV with ATLAS},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {1844},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-011-1844-6},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127530},
  year      = {2012},
  abstract  = {The measurement of missing transverse momentum in the ATLAS detector, described in this paper, makes use of the full event reconstruction and a calibration based on reconstructed physics objects. The performance of the missing transverse momentum reconstruction is evaluated using data collected in pp collisions at a centre-of-mass energy of 7 TeV in 2010. Minimum bias events and events with jets of hadrons are used from data samples corresponding to an integrated luminosity of about 0.3 nb\(^{-1}\) and 600 nb\(^{-1}\) respectively, together with events containing a Z boson decaying to two leptons (electrons or muons) or a W boson decaying to a lepton (electron or muon) and a neutrino, from a data sample corresponding to an integrated luminosity of about 36 pb\(^{-1}\). An estimate of the systematic uncertainty on the missing transverse momentum scale is presented},
  language  = {en}
}
@article{OPUS4-12735,
  title     = {Measurement of inclusive two-particle angular correlations in pp collisions with the ATLAS detector at the LHC},
  series = {Journal of High Energy Physics},
  volume    = {05},
  journal   = {Journal of High Energy Physics},
  number    = {157},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP05(2012)157},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127350},
  year      = {2012},
  abstract  = {We present a measurement of two-particle angular correlations in proton- proton collisions at √s=900 GeV and 7 TeV. The collision events were collected during 2009 and 2010 with the ATLAS detector at the Large Hadron Collider using a single-arm minimum bias trigger. Correlations are measured for charged particles produced in the kinematic range of transverse momentum p\(_T\)  > 100 MeV and pseudorapidity |η| < 2.5. A complex structure in pseudorapidity and azimuth is observed at both collision energies. Results are compared to PYTHIA 8 and HERWIG++ as well as to the AMBT2B, DW and Perugia 2011 tunes of PYTHIA 6. The data are not satisfactorily described by any of these models.},
  language  = {en}
}
@article{OPUS4-12779,
  title     = {Search for heavy neutrinos and right-handed W bosons in events with two leptons and jets in pp collisions at \(\sqrt{s}\)=7TeV with the ATLAS detector},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {2056},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2056-4},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127796},
  year      = {2012},
  abstract  = {This letter reports on a search for hypothetical heavy neutrinos, N, and right-handed gauge bosons, W R, in events with high transverse momentum objects which include two reconstructed leptons and at least one hadronic jet. The results were obtained from data corresponding to an integrated luminosity of 2.1 fb\(^{-1}\) collected in proton-proton collisions at √s=7 TeV with the ATLAS detector at the CERN Large Hadron Collider. No excess above the Standard Model background expectation is observed. Excluded mass regions for Majorana and Dirac neutrinos are presented using two approaches for interactions that violate lepton and lepton-flavor numbers. One approach uses an effective operator framework, the other approach is guided by the Left-Right Symmetric Model. The results described in this letter represent the most stringent limits to date on the masses of heavy neutrinos and W\(_R\) bosons obtained in direct searches.},
  language  = {en}
}
@article{OPUS4-12780,
  title     = {Measurement of τ polarization in W→τν decays with the ATLAS detector in pp collisions at s√=7 TeV},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {2062},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2062-6},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127807},
  year      = {2012},
  abstract  = {In this paper, a measurement of τ polarization in W→τν decays is presented. It is measured from the energies of the decay products in hadronic τ decays with a single final state charged particle. The data, corresponding to an integrated luminosity of 24 pb\(^{-1}\), were collected by the ATLAS experiment at the Large Hadron Collider in 2010. The measured value of the τ polarization is P\(_τ\)=-1.06±0.04 (stat)\(^{+0.05}_{-0.07}\) (syst), in agreement with the Standard Model prediction, and is consistent with a physically allowed 95 \% CL interval [-1,-0.91]. Measurements of τ polarization have not previously been made at hadron colliders.},
  language  = {en}
}
@article{OPUS4-12781,
  title     = {Measurement of event shapes at large momentum transfer with the ATLAS detector in pp collisions at √s=7 TeV},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {2211},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2211-y},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127813},
  year      = {2012},
  abstract  = {A measurement of event shape variables is presented for large momentum transfer proton-proton collisions using the ATLAS detector at the Large Hadron Collider. Six event shape variables calculated using hadronic jets are studied in inclusive multi-jet events in 35 pb\(^{-1}\) of integrated luminosity at a center-of-mass energy of √s=7 TeV. These measurements are compared to predictions by three Monte Carlo event generators containing leading-logarithmic parton showers matched to leading order matrix elements for 2→2 and 2→n (n=2,…,6) scattering. Measurements of the third-jet resolution parameter, aplanarity, thrust, sphericity, and transverse sphericity are generally well described. The mean value of each event shape variable is evaluated as a function of the average momentum of the two leading jets p\(_{T,1}\) and p\(_{T,2}\), with a mean p\(_T\) approaching 1 TeV.},
  language  = {en}
}
@article{OPUS4-12785,
  title     = {Search for anomaly-mediated supersymmetry breaking with the ATLAS detector based on a disappearing-track signature in pp collisions at √s=7 TeV},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {1993},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-1993-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127850},
  year      = {2012},
  abstract  = {In models of anomaly-mediated supersymmetry breaking (AMSB), the lightest chargino is predicted to have a lifetime long enough to be detected in collider experiments. This letter explores AMSB scenarios in pp collisions at √s=7 TeV by attempting to identify decaying charginos which result in tracks that appear to have few associated hits in the outer region of the tracking system. The search was based on data corresponding to an integrated luminosity of 1.02 fb\(^{-1}\) collected with the ATLAS detector in 2011. The p\(_T\) spectrum of candidate tracks is found to be consistent with the expectation from Standard Model background processes and constraints on the lifetime and the production cross section were obtained. In the minimal AMSB framework with m\(_{3/2}\)<32 TeV, m\(_0\)<1.5 TeV, tanβ=5 and μ>0, a chargino having mass below 92 GeV and a lifetime between 0.5 ns and 2 ns is excluded at 95 \% confidence level.},
  language  = {en}
}
@article{OPUS4-12795,
  title     = {A search for \(t\overline t\) resonances with the ATLAS detector in 2.05 fb\(^{-1}\) of proton-proton collisions at √s=7 TeV},
  series = {European Physical Journal C},
  volume    = {72},
  journal   = {European Physical Journal C},
  number    = {2083},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2083-1},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127959},
  year      = {2012},
  abstract  = {A search for top quark pair resonances in final states containing at least one electron or muon has been performed with the ATLAS experiment at the CERN Large Hadron Collider. The search uses a data sample corresponding to an integrated luminosity of 2.05 fb\(^{-1}\), which was recorded in 2011 at a proton-proton centre-of-mass energy of 7 TeV. No evidence for a resonance is found and limits are set on the production cross-section times branching ratio to \(t\overline t\) for narrow and wide resonances. For narrow Z′ bosons, the observed 95 \% Bayesian credibility level limits range from 9.3 pb to 0.95 pb for masses in the range of m Z′=500 GeV to m\(_{Z′}\)=1300 GeV. The corresponding excluded mass region for a leptophobic topcolour Z′ boson (Kaluza-Klein gluon excitation in the Randall-Sundrum model) is m\(_{Z′}\)<880 GeV (m\(_{gKK}\)<1130 GeV).},
  language  = {en}
}
@article{OPUS4-12796,
  title     = {Measurement of W\(^{±}\)Z production in proton-proton collisions at √s=7 TeV with the ATLAS detector},
  series = {European Physical Journal C},
  volume    = {72},
  journal   = {European Physical Journal C},
  number    = {2173},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2173-0},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127963},
  year      = {2012},
  abstract  = {A study of W\(^{±}\)Z production in proton-proton collisions at √s=7 TeV is presented using data corresponding to an integrated luminosity of 4.6 fb\(^{-1}\) collected with the ATLAS detector at the Large Hadron Collider in 2011. In total, 317 candidates, with a background expectation of 68±10 events, are observed in double-leptonic decay final states with electrons, muons and missing transverse momentum. The total cross-section is determined to be σ\(^{tot}_{WZ}\)=19.0\(^{+1.4}_{-1.3}\)(stat.)±0.9(syst.)±0.4(lumi.) pb, consistent with the Standard Model expectation of 17.6\(^{+1.1}_{-1.0}\) pb. Limits on anomalous triple gauge boson couplings are derived using the transverse momentum spectrum of Z bosons in the selected events. The cross-section is also presented as a function of Z boson transverse momentum and diboson invariant mass.},
  language  = {en}
}
@article{OPUS4-12797,
  title     = {Search for high-mass resonances decaying to dilepton final states in pp collisions at √s=7 TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {11},
  journal   = {Journal of High Energy Physics},
  number    = {138},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP11(2012)138},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127974},
  year      = {2012},
  abstract  = {The ATLAS detector at the Large Hadron Collider is used to search for high-mass resonances decaying to an electron-positron pair or a muon-antimuon pair. The search is sensitive to heavy neutral Z′ gauge bosons, Randall-Sundrum gravitons, Z* bosons, techni-mesons, Kaluza-Klein Z/γ bosons, and bosons predicted by Torsion models. Results are presented based on an analysis of pp collisions at a center-of-mass energy of 7 TeV corresponding to an integrated luminosity of 4.9 fb\(^{-1}\) in the e\(^+\)e\(^-\) channel and 5.0 fb\(^{-1}\) in the μ\(^+\)μ\(^-\)channel. A Z′ boson with Standard Model-like couplings is excluded at 95 \% confidence level for masses below 2.22 TeV. A Randall-Sundrum graviton with coupling k/\(\overline M_{Pl}\)=0.1 is excluded at 95 \% confidence level for masses below 2.16 TeV. Limits on the other models are also presented, including Technicolor and Minimal Z′ Models.},
  language  = {en}
}
@article{OPUS4-12798,
  title     = {Search for anomalous production of prompt like-sign lepton pairs at √s=7TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {12},
  journal   = {Journal of High Energy Physics},
  number    = {7},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP12(2012)007},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127983},
  year      = {2012},
  abstract  = {An inclusive search for anomalous production of two prompt, isolated leptons with the same electric charge is presented. The search is performed in a data sample corresponding to 4.7 fb\(^{-1}\) of integrated luminosity collected in 2011 at √s=7TeV with the ATLAS detector at the LHC. Pairs of leptons (e\(^{±}\)e\(^{±}\), e\(^{±}\)μ\(^{±}\), and μ\(^{±}\)μ\(^{±}\)) with large transverse momentum are selected, and the dilepton invariant mass distribution is examined for any deviation from the Standard Model expectation. No excess is found, and upper limits on the production cross section of like-sign lepton pairs from physics processes beyond the Standard Model are placed as a function of the dilepton invariant mass within a fiducial region close to the experimental selection criteria. The 95\% confidence level upper limits on the cross section of anomalous e\(^{±}\)e\(^{±}\), e\(^{±}\)μ\(^{±}\), or μ\(^{±}\)μ\(^{±}\) production range between 1.7 fb and 64 fb depending on the dilepton mass and flavour combination.},
  language  = {en}
}
@article{OPUS4-12799,
  title     = {Measurements of the pseudorapidity dependence of the total transverse energy in proton-proton collisions at √s=7 TeV with ATLAS},
  series = {Journal of High Energy Physics},
  volume    = {11},
  journal   = {Journal of High Energy Physics},
  number    = {033},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP11(2012)033},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127998},
  year      = {2012},
  abstract  = {This paper describes measurements of the sum of the transverse energy of particles as a function of particle pseudorapidity, η, in proton-proton collisions at a centre-of-mass energy, √s=7 TeV using the ATLAS detector at the Large Hadron Collider. The measurements are performed in the region |η| < 4.8 for two event classes: those requiring the presence of particles with a low transverse momentum and those requiring particles with a significant transverse momentum. In the second dataset measurements are made in the region transverse to the hard scatter. The distributions are compared to the predictions of various Monte Carlo event generators, which generally tend to underestimate the amount of transverse energy at high |η|.},
  language  = {en}
}
@article{OPUS4-12761,
  title     = {Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at √s=7 TeV with the ATLAS experiment},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {2001},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2001-6},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127615},
  year      = {2012},
  abstract  = {This paper describes an analysis of the angular distribution of W→eν and W→μν decays, using data from pp collisions at s√=7 TeV recorded with the ATLAS detector at the LHC in 2010, corresponding to an integrated luminosity of about 35 pb\(^{-1}\). Using the decay lepton transverse momentum and the missing transverse momentum, the W decay angular distribution projected onto the transverse plane is obtained and analysed in terms of helicity fractions f\(_0\), f\(_L\) and f\(_R\) over two ranges of W transverse momentum (p\(^W_T\)):35<p\(^W_T\)<50 GeV and p\(^W_T\)>50 GeV. Good agreement is found with theoretical predictions. For p\(^W_T\)>50 GeV, the values of f\(_0\) and f\(_L\)-f\(_R\), averaged over charge and lepton flavour, are measured to be: f\(_0\)=0.127±0.030±0.108 and f\(_L\)-f\(_R\)=0.252±0.017±0.030, where the first uncertainties are statistical, and the second include all systematic effects.},
  language  = {en}
}
@article{OPUS4-12762,
  title     = {Rapidity gap cross sections measured with the ATLAS detector in pp collisions at √s=7TeV},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {1926},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-1926-0},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127629},
  year      = {2012},
  abstract  = {Pseudorapidity gap distributions in proton-proton collisions at √s=7 TeV are studied using a minimum bias data sample with an integrated luminosity of 7.1 μb\(^{-1}\). Cross sections are measured differentially in terms of Δη\(^F\), the larger of the pseudorapidity regions extending to the limits of the ATLAS sensitivity, at η=±4.9, in which no final state particles are produced above a transverse momentum threshold pcutT. The measurements span the region 0<Δη\(^F\)<8 for 200MeV<p\(^{cut}_T\)<800MeV. At small Δη\(^F\) , the data test the reliability of hadronisation models in describing rapidity and transverse momentum fluctuations in final state particle production. The measurements at larger gap sizes are dominated by contributions from the single diffractive dissociation process (pp→Xp), enhanced by double dissociation (pp→XY) where the invariant mass of the lighter of the two dissociation systems satisfies M\(_Y\) ≲7 GeV. The resulting cross section is dσ/dΔη\(^F\) ≈1 mb for Δη\(^F\) ≳3. The large rapidity gap data are used to constrain the value of the Pomeron intercept appropriate to triple Regge models of soft diffraction. The cross section integrated over all gap sizes is compared with other LHC inelastic cross section measurements.},
  language  = {en}
}
@article{OPUS4-12763,
  title     = {Search for lepton flavour violation in the eμ continuum with the ATLAS detector in √s=7 TeV pp collisions at the LHC},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {2040},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2040-z},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-127632},
  year      = {2012},
  abstract  = {This paper presents a search for the t-channel exchange of an R-parity violating scalar top quark ( \(\tilde{t}\) ) in the e\(^±\) μ\(^∓\) continuum using 2.1 fb\(^{-1}\) of data collected by the ATLAS detector in √s=7 TeV pp collisions at the Large Hadron Collider. Data are found to be consistent with the expectation from the Standard Model backgrounds. Limits on R-parity-violating couplings at 95 \% C.L. are calculated as a function of the scalar top mass (m\(_\tilde{t}\)). The upper limits on the production cross section for pp→eμX, through the t-channel exchange of a scalar top quark, ranges from 170 fb for m\(_\tilde{t}\)=95 GeV to 30 fb for m\(_\tilde{t}\)=1000 GeV.},
  language  = {en}
}
@article{OPUS4-12812,
  title     = {Time-dependent angular analysis of the decay B\(^0_s\)→J/ψϕ and extraction of ΔΓ\(_s\) and the CP-violating weak phase ϕ\(_s\) by ATLAS},
  series = {Journal of High Energy Physics},
  volume    = {12},
  journal   = {Journal of High Energy Physics},
  number    = {072},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP12(2012)072},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128125},
  year      = {2012},
  abstract  = {A measurement of B\(^0_s\)→J/ψϕ decay parameters, including the CP -violating weak phase ϕ\(_s\) and the decay width difference ΔΓ\(_s\) is reported, using 4.9 fb\(^{-1}\) of integrated luminosity collected in 2011 by the ATLAS detector from LHC pp collisions at a centre-of-mass energy √s=7 TeV. The mean decay width Γ\(_s\) and the transversity amplitudes |A\(_0\)(0)|\(^2\) and |A\(_∥\)(0)|\(^2\) are also measured. The values reported for these parameters are: ϕ\(_s\)=0.22±0.41 (stat.)±0.10 (syst.) rad ΔΓ\(_s\)=0.053±0.021 (stat.)±0.010 (syst.)ps\(^{-1}\) Γ\(_s\)=0.677±0.007 (stat.)±0.004 (syst.) ps\(^{-1}\) |A\(_0\)(0)|\(^2\)=0.528±0.006 (stat.)±0.009 (syst.) |A\(_∥\)(0)|\(^2\)=0.220±0.008 (stat.)±0.007 (syst.) where the values quoted for ϕ\(_s\) and ΔΓ\(_s\) correspond to the solution compatible with the external measurements to which the strong phase δ\(_⊥\) is constrained and where ΔΓ\(_s\) is constrained to be positive. The fraction of S-wave KK or f\(_0\) contamination through the decays B\(^0_s\)→J/ψK\(^+\)K\(^-\)(f\(_0\)) is measured as well and is found to be consistent with zero. Results for ϕ\(_s\) and ΔΓ\(_s\) are also presented as 68\%, 90\% and 95\% likelihood contours, which show agreement with Standard Model expectations.},
  language  = {en}
}
@article{OPUS4-12813,
  title     = {Search for pair production of massive particles decaying into three quarks with the ATLAS detector in √s=7TeV pp collisions at the LHC},
  series = {Journal of High Energy Physics},
  volume    = {12},
  journal   = {Journal of High Energy Physics},
  number    = {86},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP12(2012)086},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128133},
  year      = {2012},
  abstract  = {A search is conducted for hadronic three-body decays of a new massive coloured particle in √s=7TeV pp collisions at the LHC using an integrated luminosity of 4.6 fb\(^{-1}\) collected by the ATLAS detector. Supersymmetric gluino pair production in the context of a model with R-parity violation is used as a benchmark scenario. The analysis is divided into two search channels, each optimised separately for their sensitivity to high-mass and low-mass gluino production. The first search channel uses a stringent selection on the transverse momentum of the six leading jets and is performed as a counting experiment. The second search channel focuses on low-mass gluinos produced with a large boost. Large-radius jets are selected and the invariant mass of each of the two leading jets is used as a discriminant between the signal and the background. The results are found to be consistent with Standard Model expectations and limits are set on the allowed gluino mass.},
  language  = {en}
}
@article{OPUS4-22072,
  title     = {Search for Higgs boson decays to beyond-the-Standard-Model light bosons in four-lepton events with the ATLAS detector at root s=13 TeV},
  series = {Journal of High Energy Physics},
  volume    = {166},
  journal   = {Journal of High Energy Physics},
  number    = {6},
  organization    = {The ATLAS collaboration},
  doi       = {10.1007/JHEP06(2018)166},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220721},
  pages     = {1-50},
  year      = {2018},
  abstract  = {A search is conducted for a beyond-the-Standard-Model boson using events where a Higgs boson with mass 125 GeV decays to four leptons (l = e or mu). This decay is presumed to occur via an intermediate state which contains one or two on-shell, promptly decaying bosons: H -> ZX/XX -> 4l , where X is a new vector boson Z(d) or pseudoscalar a with mass between 1 and 60 GeV. The search uses pp collision data collected with the ATLAS detector at the LHC with an integrated luminosity of 36.1 fb(-1) at a centre-of-mass energy root s = 13TeV. No significant excess of events above Standard Model background predictions is observed; therefore, upper limits at 95\% confidence level are set on model-independent fiducial cross-sections, and on the Higgs boson decay branching ratios to vector and pseudoscalar bosons in two benchmark models.},
  language  = {en}
}
@article{OPUS4-12915,
  title     = {A search for flavour changing neutral currents in top-quark decays in pp collision data collected with the ATLAS detector at √s=7 TeV},
  series = {Journal of High Energy Physics},
  volume    = {9},
  journal   = {Journal of High Energy Physics},
  number    = {139},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP09(2012)139},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-129152},
  year      = {2012},
  abstract  = {A search for flavour changing neutral current (FCNC) processes in top-quark decays by the ATLAS Collaboration is presented. Data collected from pp collisions at the LHC at a centre-of-mass energy of √s=7TeV during 2011, corresponding to an integrated luminosity of 2.1 fb\(^{-1}\), were used. A search was performed for top-quark pair-production events, with one top quark decaying through the t → Zq FCNC (q = u, c) channel, and the other through the Standard Model dominant mode t → W b. Only the decays of the Z boson to charged leptons and leptonic W -boson decays were considered as signal. Consequently, the final-state topology is characterised by the presence of three isolated charged leptons, at least two jets and missing transverse momentum from the undetected neutrino. No evidence for an FCNC signal was found. An upper limit on the t → Zq branching ratio of BR(t → Zq) < 0.73\% is set at the 95\% confidence level.},
  language  = {en}
}
@article{OPUS4-12916,
  title     = {Search for charged Higgs bosons decaying via H\(^±\) → τν in \(t\overline t\) events using pp collision data at √s=7 TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {06},
  journal   = {Journal of High Energy Physics},
  number    = {39},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP06(2012)039},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-129163},
  year      = {2012},
  abstract  = {The results of a search for charged Higgs bosons are presented. The analysis is based on 4.6fb\(^{-1}\) of proton-proton collision data at √s=7TeV collected by the ATLAS experiment at the Large Hadron Collider, using top quark pair events with a τ lepton in the final state. The data are consistent with the expected background from Standard Model processes. Assuming that the branching ratio of the charged Higgs boson to a τ lepton and a neutrino is 100 \%, this leads to upper limits on the branching ratio of top quark decays to a b quark and a charged Higgs boson between 5\% and 1\% for charged Higgs boson masses ranging from 90 GeV to 160 GeV, respectively. In the context of the m\(^{max}_h\) scenario of the MSSM, tan β above 12-26, as well as between 1 and 2-6, can be excluded for charged Higgs boson masses between 90 GeV and 150 GeV.},
  language  = {en}
}
@article{OPUS4-12917,
  title     = {Search for R-parity-violating supersymmetry in events with four or more leptons in √s=7 TeV pp collisions with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {12},
  journal   = {Journal of High Energy Physics},
  number    = {124},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP12(2012)124},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-129179},
  year      = {2012},
  abstract  = {A search for new phenomena in final states with four or more leptons (electrons or muons) is presented. The analysis is based on 4.7 fb\(^{-1}\) of √s=7 TeV proton-proton collisions delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in two signal regions: one that requires moderate values of missing transverse momentum and another that requires large effective mass. The results are interpreted in a simplified model of R-parity-violating supersymmetry in which a 95\% CL exclusion region is set for charged wino masses up to 540 GeV. In an R-parity-violating MSUGRA/CMSSM model, values of m 1/2 up to 820 GeV are excluded for 10 < tan β < 40.},
  language  = {en}
}
@article{OPUS4-13985,
  title     = {Centrality and rapidity dependence of inclusive jet production in \(\sqrt{^SNN}\)=5.02 TeV proton-lead collisions with the ATLAS detector},
  series = {Physics Letters B},
  volume    = {748},
  journal   = {Physics Letters B},
  organization    = {ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2015.07.023},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-139857},
  pages     = {392-413},
  year      = {2015},
  abstract  = {Measurements of the centrality and rapidity dependence of inclusive jet production in \(\sqrt{^SNN}\)=5.02 TeV proton-lead (p+Pb) collisions and the jet cross-section in \(\sqrt{s}\)=2.76 TeV proton-proton collisions are presented. These quantities are measured in datasets corresponding to an integrated luminosity of 27.8 nb\(^{-1}\) and 4.0 pb\(^{-1}\), respectively, recorded with the ATLAS detector at the Large Hadron Collider in 2013. The p+Pb collision centrality was characterised using the total transverse energy measured in the pseudorapidity interval -4.9<η<-3.2 in the direction of the lead beam. Results are presented for the double-differential per-collision yields as a function of jet rapidity and transverse momentum (\(p_T\)) for minimum-bias and centrality-selected p+Pb collisions, and are compared to the jet rate from the geometric expectation. The total jet yield in minimum-bias events is slightly enhanced above the expectation in a \(p_T\)-dependent manner but is consistent with the expectation within uncertainties. The ratios of jet spectra from different centrality selections show a strong modification of jet production at all \(p_T\) at forward rapidities and for large \(p_T\) at mid-rapidity, which manifests as a suppression of the jet yield in central events and an enhancement in peripheral events. These effects imply that the factorisation between hard and soft processes is violated at an unexpected level in proton-nucleus collisions. Furthermore, the modifications at forward rapidities are found to be a function of the total jet energy only, implying that the violations may have a simple dependence on the hard parton-parton kinematics.},
  language  = {en}
}
@article{OPUS4-13986,
  title     = {Search for s-channel single top-quark production in proton-proton collisions at \(\sqrt{s}\)=8 TeV with the ATLAS detector},
  series = {Physics Letters B},
  volume    = {740},
  journal   = {Physics Letters B},
  organization    = {ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2014.11.042},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-139869},
  pages     = {118-136},
  year      = {2015},
  abstract  = {This Letter presents a search at the LHC for s-channel single top-quark production in proton-proton collisions at a centre-of-mass energy of 8 TeV. The analyzed data set was recorded by the ATLAS detector and corresponds to an integrated luminosity of 20.3 fb\(^{-1}\). Selected events contain one charged lepton, large missing transverse momentum and exactly two b-tagged jets. A multivariate event classifier based on boosted decision trees is developed to discriminate s-channel single top-quark events from the main background contributions. The signal extraction is based on a binned maximum-likelihood fit of the output classifier distribution. The analysis leads to an upper limit on the s-channel single top-quark production cross-section of 14.6 pb at the 95\% confidence level. The fit gives a cross-section of σs=5.0±4.3 pb, consistent with the Standard Model expectation.},
  language  = {en}
}
@article{OPUS4-13826,
  title     = {Search for \(W′→t\overline {b}\) in the lepton plus jets final state in proton-proton collisions at a centre-of-mass energy of \(\sqrt {s}\)=8 TeV with the ATLAS detector},
  series = {Physics Letters B},
  volume    = {743},
  journal   = {Physics Letters B},
  organization    = {ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2015.02.051},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-138262},
  pages     = {235-255},
  year      = {2015},
  abstract  = {A search for new charged massive gauge bosons, called W′W′, is performed with the ATLAS detector at the LHC, in proton-proton collisions at a centre-of-mass energy of \(\sqrt {s}\)=8 TeV, using a dataset corresponding to an integrated luminosity of 20.3 fb\(^{-1}\). This analysis searches for W′W′ bosons in the \(W′→t\overline{b}\) 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′W′ bosons. No significant deviation from the Standard Model expectation is observed and limits are set on the \(W′→t\overline{b}\) cross-section times branching ratio and on the W′W′-boson effective couplings as a function of the W′W′-boson mass using the CL\(_s\) procedure. For a left-handed (right-handed) W′W′ boson, masses below 1.70 (1.92) TeV are excluded at 95\% confidence level.},
  language  = {en}
}
@article{OPUS4-13827,
  title     = {Search for the \(X_b\) and other hidden-beauty states in the \(π^+π^-ϒ\)(1S) channel at ATLAS},
  series = {Physics Letters B},
  volume    = {740},
  journal   = {Physics Letters B},
  organization    = {ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2014.11.055},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-138273},
  pages     = {199-217},
  year      = {2014},
  abstract  = {This Letter presents a search for a hidden-beauty counterpart of the X(3872) in the mass ranges of 10.05-10.31 GeV and 10.40-11.00 GeV, in the channel X\(_b\)→π\(^+\)π\(^-\)ϒ(1S)(→μ\(^+\)μ\(^-\)), using 16.2 fb\(^{-1}\) of s=8 TeV \(pp\) collision data collected by the ATLAS detector at the LHC. No evidence for new narrow states is found, and upper limits are set on the product of the X\(_b\) cross section and branching fraction, relative to those of the ϒ(2S), at the 95\% confidence level using the CLSCLS approach. These limits range from 0.8\% to 4.0\%, depending on mass. For masses above 10.1 GeV, the expected upper limits from this analysis are the most restrictive to date. Searches for production of the ϒ(1\(^3\)D\(_J\)), ϒ(10860), and ϒ(11020) states also reveal no significant signals.},
  language  = {en}
}
@article{OPUS4-13609,
  title     = {Search for pair-produced long-lived neutral particles decaying to jets in the ATLAS hadronic calorimeter in pp collisions at \(\sqrt{2}\)=8 TeV},
  series = {Physics Letters B},
  volume    = {743},
  journal   = {Physics Letters B},
  organization    = {ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2015.02.015},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-136099},
  pages     = {15-34},
  year      = {2015},
  abstract  = {The ATLAS detector at the Large Hadron Collider at CERN is used to search for the decay of a scalar boson to a pair of long-lived particles, neutral under the Standard Model gauge group, in 20.3 fb-120.3 fb\(^{-1}\) of data collected in proton-proton collisions at \(\sqrt{2}\)=8 TeV. This search is sensitive to long-lived particles that decay to Standard Model particles producing jets at the outer edge of the ATLAS electromagnetic calorimeter or inside the hadronic calorimeter. No significant excess of events is observed. Limits are reported on the product of the scalar boson production cross section times branching ratio into long-lived neutral particles as a function of the proper lifetime of the particles. Limits are reported for boson masses from 100 GeV to 900 GeV, and a long-lived neutral particle mass from 10 GeV to 150 GeV.},
  language  = {en}
}
@article{OPUS4-13610,
  title     = {Search for H→γγH→γγ produced in association with top quarks and constraints on the Yukawa coupling between the top quark and the Higgs boson using data taken at 7 TeV and 8 TeV with the ATLAS detector},
  series = {Physics Letters B},
  volume    = {740},
  journal   = {Physics Letters B},
  organization    = {ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2014.11.049},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-136100},
  pages     = {222-242},
  year      = {2015},
  abstract  = {A search is performed for Higgs bosons produced in association with top quarks using the diphoton decay mode of the Higgs boson. Selection requirements are optimized separately for leptonic and fully hadronic final states from the top quark decays. The dataset used corresponds to an integrated luminosity of 4.5 fb\(^{-1}\) of proton-proton collisions at a center-of-mass energy of 7 TeV and 20.3 fb-120.3 fb\(^{-1}\) at 8 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. No significant excess over the background prediction is observed and upper limits are set on the \(t\overline{t}H\) production cross section. The observed exclusion upper limit at 95\% confidence level is 6.7 times the predicted Standard Model cross section value. In addition, limits are set on the strength of the Yukawa coupling between the top quark and the Higgs boson, taking into account the dependence of the \(t\overline{t}H\) and tH   cross sections as well as the H→γγH→γγ branching fraction on the Yukawa coupling. Lower and upper limits at 95\% confidence level are set at -1.3 and +8.0 times the Yukawa coupling strength in the Standard Model.},
  language  = {en}
}
@article{OPUS4-13153,
  title     = {Measurement of hard double-parton interactions in W(→ℓν) + 2-jet events at \(\sqrt{s}=7\) TeV with the ATLAS detector},
  series = {New Journal of Physics},
  volume    = {15},
  journal   = {New Journal of Physics},
  number    = {033038},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1088/1367-2630/15/3/033038},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131531},
  year      = {2013},
  abstract  = {The production of W bosons in association with two jets in proton-proton collisions at a centre-of-mass energy of \(\sqrt{s}=7\),TeV has been analysed for the presence of double-parton interactions using data corresponding to an integrated luminosity of \(36 pb^{-1}\), collected with the ATLAS detector at the Large Hadron Collider. The fraction of events arising from double-parton interactions, \(f^D_{DP}\), has been measured through the pT balance between the two jets and amounts to \(f^D_{DP}\) = 0.08 ± 0.01 (stat.) ± 0.02 (sys.) for jets with transverse momentum \(p_T\) > 20 GeV and rapidity |y| < 2.8. This corresponds to a measurement of the effective area parameter for hard double-parton interactions of \(\sigma_{eff} = 15 ± 3 (stat.)^{+5}_{-3} (sys.)\) mb.},
  language  = {en}
}
@article{OPUS4-13154,
  title     = {Search for extra dimensions in diphoton events from proton-proton collisions at \(\sqrt {s} = 7\)  TeV in the ATLAS detector at the LHC},
  series = {New Journal of Physics},
  volume    = {15},
  journal   = {New Journal of Physics},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1088/1367-2630/15/4/043007},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131548},
  pages     = {043007},
  year      = {2013},
  abstract  = {The large difference between the Planck scale and the electroweak scale, known as the hierarchy problem, is addressed in certain models through the postulate of extra spatial dimensions. A search for evidence of extra spatial dimensions in the diphoton channel has been performed using the full set of proton-proton collisions at \(\sqrt {s} = 7\) TeV recorded in 2011 with the ATLAS detector at the CERN Large Hadron Collider. This dataset corresponds to an integrated luminosity of \(4.9 fb^{-1}\). The diphoton invariant mass spectrum is observed to be in good agreement with the Standard Model expectation. In the context of the model proposed by Arkani-Hamed, Dimopoulos and Dvali, 95\% confidence level lower limits of between 2.52 and 3.92 TeV are set on the ultraviolet cutoff scale MS depending on the number of extra dimensions and the theoretical formalism used. In the context of the Randall-Sundrum model, a lower limit of 2.06 (1.00) TeV at 95\% confidence level is set on the mass of the lightest graviton for couplings of \(k/\overline {M}_{Pl} = 0.1 (0.01)\). Combining with the ATLAS dilepton searches based on the 2011 data, the 95\% confidence level lower limit on the Randall-Sundrum graviton mass is further tightened to 2.23 (1.03) TeV for \(k/\overline {M}_{Pl} = 0.1 (0.01)\).},
  language  = {en}
}
@article{OPUS4-12954,
  title     = {Search for doubly charged Higgs bosons in like-sign dilepton final states at √s=7 TeV with the ATLAS detector},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {2244},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2244-2},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-129540},
  year      = {2012},
  abstract  = {A search for doubly charged Higgs bosons decaying to pairs of electrons and/or muons is presented. The search is performed using a data sample corresponding to an integrated luminosity of 4.7 fb\(^{-1}\) of pp collisions at √s = 7 TeV collected by the ATLAS detector at the LHC. Pairs of prompt, isolated, high-p\(_T\) leptons with the same electric charge (\(e^±e^±, e^±μ^±, μ^±μ^±\)) are selected, and their invariant mass distribution is searched for a narrow resonance. No significant excess over Standard Model background expectations is observed, and limits are placed on the cross section times branching ratio for pair production of doubly charged Higgs bosons. The masses of doubly charged Higgs bosons are constrained depending on the branching ratio into these leptonic final states. Assuming pair production, coupling to left-handed fermions, and a branching ratio of 100 \% for each final state, masses below 409 GeV, 375 GeV, and 398 GeV are excluded for \(e^±e^±, e^±μ^±\), and \(μ^±μ^±\), respectively.},
  language  = {en}
}
@article{OPUS4-12955,
  title     = {A search for \(t\overline t\) resonances in lepton+jets events with highly boosted top quarks collected in pp collisions at √s=7 TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {09},
  journal   = {Journal of High Energy Physics},
  number    = {41},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP09(2012)041},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-129555},
  year      = {2012},
  abstract  = {A search for resonant production of high-mass top-quark pairs is performed on 2.05 fb\(^{-1}\) of proton-proton collisions at √s=7 TeV collected in 2011 with the ATLAS experiment at the Large Hadron Collider. This analysis of the lepton+jets final state is specifically designed for the particular topology that arises from the decay of highly boosted top quarks. The observed \(t\overline t\) invariant mass spectrum is found to be compatible with the Standard Model prediction and 95\% credibility level upper limits are derived on the \(t\overline t\) production rate through new massive states. An upper limit of 0.7 pb is set on the production cross section times branching fraction of a narrow 1 TeV resonance. A Kaluza-Klein gluon with a mass smaller than 1.5 TeV is excluded.},
  language  = {en}
}
@article{OPUS4-12956,
  title     = {Search for light scalar top-quark pair production in final states with two leptons with the ATLAS detector in √s=7 TeV proton-proton collisions},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {2237},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2237-1},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-129561},
  year      = {2012},
  abstract  = {A search is presented for the pair production of light scalar top quarks in √s=7 TeV proton-proton collisions recorded with the ATLAS detector at the Large Hadron Collider. This analysis uses the full data sample collected during 2011 running that corresponds to a total integrated luminosity of 4.7 fb\(^{-1}\). Light scalar top quarks are searched for in events with two opposite-sign leptons (e, μ), large missing transverse momentum and at least one jet in the final state. No excess over Standard Model expectations is found, and the results are interpreted under the assumption that the light scalar top decays to a b-quark in addition to an on-shell chargino whose decay occurs through a virtual W boson. If the chargino mass is 106 GeV, light scalar top-quark masses up to 130 GeV are excluded for neutralino masses below 70 GeV.},
  language  = {en}
}
@article{OPUS4-12888,
  title     = {ATLAS search for a heavy gauge boson decaying to a charged lepton and a neutrino in pp collisions at √s=7 TeV},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {2241},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2241-5},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128888},
  year      = {2012},
  abstract  = {The ATLAS detector at the LHC is used to search for high-mass states, such as heavy charged gauge bosons (W′), decaying to a charged lepton (electron or muon) and a neutrino. Results are presented based on the analysis of pp collisions at a center-of-mass energy of 7 TeV corresponding to an integrated luminosity of 4.7 fb\(^{-1}\). No excess beyond Standard Model expectations is observed. A W′ with Sequential Standard Model couplings is excluded at the 95 \% credibility level for masses up to 2.55 TeV. Excited chiral bosons (W∗) with equivalent coupling strength are excluded for masses up to 2.42 TeV.},
  language  = {en}
}
@article{OPUS4-12889,
  title     = {Search for supersymmetry in events with large missing transverse momentum, jets, and at least one tau lepton in 7 TeV proton-proton collision data with the},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {2215},
  organization    = {ATLAS Collaboration},
  doi       = {dx.doi.org/10.1140/epjc/s10052-012-2215-7},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128891},
  year      = {2012},
  abstract  = {A search for supersymmetry (SUSY) in events with large missing transverse momentum, jets, and at least one hadronically decaying τ lepton, with zero or one additional light lepton (e/μ), has been performed using 4.7 fb\(^{-1}\) of proton-proton collision data at \(\sqrt s\)=7TeV recorded with the ATLAS detector at the Large Hadron Collider. No excess above the Standard Model background expectation is observed and a 95 \% confidence level visible cross-section upper limit for new phenomena is set. In the framework of gauge-mediated SUSY-breaking models, lower limits on the mass scale Λ are set at 54 TeV in the regions where the \(\tilde τ_1\) is the next-to-lightest SUSY particle (tanβ>20). These limits provide the most stringent tests to date of GMSB models in a large part of the parameter space considered.},
  language  = {en}
}
@article{OPUS4-12890,
  title     = {Measurement of the charge asymmetry in top quark pair production in pp collisions at √s=7 TeV using the ATLAS detector},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {2039},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2039-5},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128904},
  year      = {2012},
  abstract  = {A measurement of the top-antitop production charge asymmetry A C is presented using data corresponding to an integrated luminosity of 1.04 fb\(^{-1}\) of pp collisions at √s=7 TeV collected by the ATLAS detector at the LHC. Events are selected with a single lepton (electron or muon), missing transverse momentum and at least four jets of which at least one jet is identified as coming from a b-quark. A kinematic fit is used to reconstruct the t\(\overline t\) event topology. After background subtraction, a Bayesian unfolding procedure is performed to correct for acceptance and detector effects. The measured value of A\(_C\) is AC=-0.019±0.028 (stat.)±0.024 (syst.), consistent with the prediction from the MC@NLO Monte Carlo generator of A\(_C\) =0.006±0.002. Measurements of A\(_C\) in two ranges of invariant mass of the top-antitop pair are also shown.},
  language  = {en}
}
@article{OPUS4-12891,
  title     = {Measurement of the top quark mass with the template method in the \(t\overline t\)→lepton+jets channel using ATLAS data},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {2046},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2046-6},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128912},
  year      = {2012},
  abstract  = {The top quark mass has been measured using the template method in the \(t\overline t\)→lepton+jets channel based on data recorded in 2011 with the ATLAS detector at the LHC. The data were taken at a proton-proton centre-of-mass energy of √s=7 TeV and correspond to an integrated luminosity of 1.04 fb\(^{-1}\). The analyses in the e+jets and μ+jets decay channels yield consistent results. The top quark mass is measured to be m\(_{top}\)=174.5±0.6\(_{stat}\)±2.3\(_{syst}\) GeV.},
  language  = {en}
}
@article{OPUS4-12892,
  title     = {Measurement of the cross section for top-quark pair production in pp collisions at √s=7TeV with the ATLAS detector using final states with two high-p\(_T\) leptons},
  series = {Journal of High Energy Physics},
  volume    = {5},
  journal   = {Journal of High Energy Physics},
  number    = {59},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP05(2012)059},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128924},
  year      = {2012},
  abstract  = {A measurement is reported of the production cross section of top-quark pairs (\(t\overline t\)) in proton-proton collisions at a center-of-mass energy of 7 TeV recorded with the ATLAS detector at the LHC. Candidate events have a signature consistent with containing two isolated leptons, large missing transverse momentum, and at least two jets. Using a data sample corresponding to an integrated luminosity of 0.70 fb\(^{-1}\), a \(t\overline t\) production cross section σ\(_{t\overline t}\)=176±5(stat.)\(^{+14}_{-11}\)(syst.)±8(lum.) pb is measured for an assumed top-quark mass of m\(_t\)  = 172.5 GeV. This measurement is in good agreement with Standard Model predictions.},
  language  = {en}
}
@article{OPUS4-12893,
  title     = {Measurement of \(t\overline t\) production with a veto on additional central jet activity in pp collisions at √s=7 TeV using the ATLAS detector},
  series = {European Physical Journal C},
  volume    = {72},
  journal   = {European Physical Journal C},
  number    = {2043},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2043-9},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128931},
  year      = {2012},
  abstract  = {A measurement of the jet activity in \(t\overline t\) events produced in proton-proton collisions at a centre-of-mass energy of 7 TeV is presented, using 2.05 fb\(^{-1}\) of integrated luminosity collected by the ATLAS detector at the Large Hadron Collider. The \(t\overline t\) events are selected in the dilepton decay channel with two identified b-jets from the top quark decays. Events are vetoed if they contain an additional jet with transverse momentum above a threshold in a central rapidity interval. The fraction of events surviving the jet veto is presented as a function of this threshold for four different central rapidity interval definitions. An alternate measurement is also performed, in which events are vetoed if the scalar transverse momentum sum of the additional jets in each rapidity interval is above a threshold. In both measurements, the data are corrected for detector effects and compared to the theoretical models implemented in MC@NLO, Powheg, Alpgen and Sherpa. The experimental uncertainties are often smaller than the spread of theoretical predictions, allowing deviations between data and theory to be observed in some regions of phase space.},
  language  = {en}
}
@article{OPUS4-13155,
  title     = {Search for excited electrons and muons in \(\sqrt {s}=8\) TeV proton-proton collisions with the ATLAS detector},
  series = {New Journal of Physics},
  volume    = {15},
  journal   = {New Journal of Physics},
  number    = {093011},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1088/1367-2630/15/9/093011},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131557},
  year      = {2013},
  abstract  = {The ATLAS detector at the Large Hadron Collider is used to search for excited electrons and excited muons in the channel \(pp →ℓℓ^\ast→ℓℓ\gamma \), assuming that excited leptons are produced via contact interactions. The analysis is based on \(13 fb^{-1}\) of pp collisions at a centre-of-mass energy of 8 TeV. No evidence for excited leptons is found, and a limit is set at the 95\% credibility level on the cross section times branching ratio as a function of the excitedlepton mass \(m_{ℓ^\ast}\) . For \(m_{ℓ^\ast}\) ≽0.8 TeV, the respective upper limits on \(\sigma B(ℓ→ ℓ\gamma)\) are 0.75 and 0.90 fb for the \(e^\ast\) and \(μ^\ast\) searches. Limits on \(\sigma B\) are converted into lower bounds on the compositeness scale \(\Lambda\). In the special case where \(\Lambda = m_{ℓ^\ast}\), excited-electron and excited-muon masses below 2.2 TeV are excluded.},
  language  = {en}
}
@article{OPUS4-13156,
  title     = {Search for WH production with a light Higgs boson decaying to prompt electron-jets in proton-proton collisions at \(\sqrt {s}=7\)  TeV with the ATLAS detector},
  series = {New Journal of Physics},
  volume    = {15},
  journal   = {New Journal of Physics},
  number    = {043009},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1088/1367-2630/15/4/043009},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-131565},
  year      = {2013},
  abstract  = {A search is performed for WH production with a light Higgs boson decaying to hidden-sector particles resulting in clusters of collimated electrons, known as electron-jets. The search is performed with \(2.04 fb^{-1}\) of data collected in 2011 with the ATLAS detector at the Large Hadron Collider in proton-proton collisions at \(\sqrt {s}=7 TeV\) . One event satisfying the signal selection criteria is observed, which is consistent with the expected background rate. Limits on the product of the WH production cross section and the branching ratio of a Higgs boson decaying to prompt electron-jets are calculated as a function of a Higgs boson mass in the range from 100 to 140 GeV.},
  language  = {en}
}
@article{OPUS4-12959,
  title     = {Hunt for new phenomena using large jet multiplicities and missing transverse momentum with ATLAS in 4.7 fb\(^{-1}\) of √s=7TeV proton-proton collisions},
  series = {The Journal of High Energy Physics},
  volume    = {07},
  journal   = {The Journal of High Energy Physics},
  number    = {167},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP07(2012)167},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-129591},
  year      = {2012},
  abstract  = {Results are presented of a search for new particles decaying to large numbers of jets in association with missing transverse momentum, using 4.7 fb\(^{-1}\) of pp collision data at √s=7TeV collected by the ATLAS experiment at the Large Hadron Collider in 2011. The event selection requires missing transverse momentum, no isolated electrons or muons, and from ≥6 to ≥9 jets. No evidence is found for physics beyond the Standard Model. The results are interpreted in the context of a MSUGRA/CMSSM supersymmetric model, where, for large universal scalar mass m 0, gluino masses smaller than 840 GeV are excluded at the 95\% confidence level, extending previously published limits. Within a simplified model containing only a gluino octet and a neutralino, gluino masses smaller than 870 GeV are similarly excluded for neutralino masses below 100 GeV.},
  language  = {en}
}
@article{OPUS4-12895,
  title     = {Search for second generation scalar leptoquarks in pp collisions at √s=7 TeV with the ATLAS detector},
  series = {The European Physical Journal C},
  volume    = {72},
  journal   = {The European Physical Journal C},
  number    = {2151},
  organization    = {ATLAS Collaboration},
  doi       = {10.1140/epjc/s10052-012-2151-6},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128957},
  year      = {2012},
  abstract  = {The results of a search for the production of second generation scalar leptoquarks are presented for final states consisting of either two muons and at least two jets or a muon plus missing transverse momentum and at least two jets. A total of 1.03 fb\(^{-1}\) integrated luminosity of proton-proton collision data produced by the Large Hadron Collider at s√=7 TeV and recorded by the ATLAS detector is used for the search. The event yields in the signal regions are found to be consistent with the Standard Model background expectations. The production of second generation leptoquarks is excluded for a leptoquark mass m\(_{LQ}\)<594 (685) GeV at 95 \% confidence level, for a branching ratio of 0.5 (1.0) for leptoquark decay to a muon and a quark.},
  language  = {en}
}
@article{OPUS4-12896,
  title     = {Search for same-sign top-quark production and fourth-generation down-type quarks in pp collisions at √s=7 TeV with the ATLAS detector},
  series = {Journal of High Energy Physics},
  volume    = {04},
  journal   = {Journal of High Energy Physics},
  number    = {69},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP04(2012)069},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128960},
  year      = {2012},
  abstract  = {A search is presented for same-sign top-quark production and down-type heavy quarks of charge -1/3 in events with two isolated leptons (e or μ) that have the same electric charge, at least two jets and large missing transverse momentum. The data are selected from pp collisions at √s=7TeV recorded by the ATLAS detector and correspond to an integrated luminosity of 1.04 fb\(^{-1}\). The observed data are consistent with expectations from Standard Model processes. Upper limits are set at 95 \% confidence level on the cross section of new sources of same-sign top-quark pair production of 1.4-2.0 pb depending on the assumed mediator mass. Upper limits are also set on the pair-production cross-section for new heavy down-type quarks; a lower limit of 450 GeV is set at 95 \% confidence level on the mass of heavy down-type quarks under the assumption that they decay 100 \% of the time to W t.},
  language  = {en}
}
@article{OPUS4-12897,
  title     = {Jet mass and substructure of inclusive jets in √s=7 TeV pp collisions with the ATLAS experiment},
  series = {Journal of High Energy Physics},
  volume    = {05},
  journal   = {Journal of High Energy Physics},
  number    = {128},
  organization    = {ATLAS Collaboration},
  doi       = {10.1007/JHEP05(2012)128},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-128970},
  year      = {2012},
  abstract  = {Recent studies have highlighted the potential of jet substructure techniques to identify the hadronic decays of boosted heavy particles. These studies all rely upon the assumption that the internal substructure of jets generated by QCD radiation is well understood. In this article, this assumption is tested on an inclusive sample of jets recorded with the ATLAS detector in 2010, which corresponds to 35 pb\(^{-1}\) of pp collisions delivered by the LHC at √s=7TeV. In a subsample of events with single pp collisions, measurements corrected for detector efficiency and resolution are presented with full systematic uncertainties. Jet invariant mass, k\(_t\) splitting scales and N-subjettiness variables are presented for anti-k\(_t\) R = 1.0 jets and Cambridge-Aachen R = 1.2 jets. Jet invariant-mass spectra for Cambridge-Aachen R = 1.2 jets after a splitting and filtering procedure are also presented. Leading-order parton-shower Monte Carlo predictions for these variables are found to be broadly in agreement with data. The dependence of mean jet mass on additional pp interactions is also explored.},
  language  = {en}
}
@inproceedings{OPUS4-9740,
  title     = {Media Psychology - "Media Research: Yesterday, Today, and Tomorrow" Proceedings of the 8th Conference of the Media Psychology Division of the German Psychological Society},
  editor    = {Schwab, Frank and Carolus, Astrid and Brill, Michael and Hennighausen, Christine},
  isbn      = {978-3-923959-93-8},
  doi       = {10.25972/OPUS-9740},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-97403},
  pages     = {105},
  year      = {2013},
  abstract  = {The proceedings of the 8th Conference of the Media Psychology Division of the German Psychological Society hosted by the University of Wuerzburg from the 4th until the 6th of September 2013 contains the abstracts of the conference participants. Following the motto of the conference "Media Research: Yesterday, Today, and Tomorrow" a large number of media-psychological topics was dealt with. Amongst others, participants presented their research on interactive learning, emotions, virtual agents and avatars, gaming, scientific communication, politics, motion pictures and entertainment, social media, methods, and persuasions.},
  subject      = {Deutsche Gesellschaft f{\"u}r Psychologie / Fachgruppe Medienpsychologie},
  language  = {en}
}
@article{OPUS4-22578,
  title     = {Search for diboson resonances with boson-tagged jets in \({pp}\) collisions at root S=13 TeV with the ATLAS detector},
  series = {Physics Letters B},
  volume    = {777},
  journal   = {Physics Letters B},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2017.12.011},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225782},
  pages     = {91-113},
  year      = {2018},
  abstract  = {Narrow resonances decaying into WW, WZ or ZZ boson pairs are searched for in 36.7 fb(-1) of proton-proton collision data at a centre-of-mass energy of root s = 13 TeV recorded with the ATLAS detector at the Large Hadron Collider in 2015 and 2016. The diboson system is reconstructed using pairs of large-radius jets with high transverse momentum and tagged as compatible with the hadronic decay of high-momentum Wor Zbosons, using jet mass and substructure properties. The search is sensitive to diboson resonances with masses in the range 1.2-5.0 TeV. No significant excess is observed in any signal region. Exclusion limits are set at the 95\% confidence level on the production cross section times branching ratio to dibosons for a range of theories beyond the Standard Model. Model-dependent lower limits on the mass of new gauge bosons are set, with the highest limit set at 3.5 TeV in the context of mass-degenerate resonances that couple predominantly to bosons. (c) 2017 The Author(s). Published by Elsevier B.V.},
  language  = {en}
}
@article{OPUS4-22540,
  title     = {Measurement of the production cross-section of a single top quark in association with a \(Z\) boson in proton-proton collisions at 13 TeV with the ATLAS detector},
  series = {Physics letters B},
  volume    = {780},
  journal   = {Physics letters B},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2018.03.023},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225406},
  pages     = {557-577},
  year      = {2018},
  abstract  = {The production of a top quark in association with a Z boson is investigated. The proton-proton collision data collected by the ATLAS experiment at the LHC in 2015 and 2016 at a centre-of-mass energy of root s = 13 TeV are used, corresponding to an integrated luminosity of 36.1 fb(-1). Events containing three identified leptons (electrons and/or muons) and two jets, one of which is identified as a b-quark jet are selected. The major backgrounds are diboson, tt(\$)over-bar and Z + jets production. A neural network is used to improve the background rejection and extract the signal. The resulting significance is 4.2 sigma in the data and the expected significance is 5.4 sigma. The measured cross-section for tZq production is 600 +/- 170(stat.)+/- 140(syst.)fb. (C) 2018 The Author(s). Published by Elsevier B.V.},
  language  = {en}
}
@article{OPUS4-22543,
  title     = {A search for resonances decaying into a Higgs boson and a new particle \(X\) in the \({XH}\) -> \({qqbb}\) final state with the ATLAS detector},
  series = {Physics letters B},
  volume    = {779},
  journal   = {Physics letters B},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2018.01.042},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225435},
  pages     = {24-45},
  year      = {2018},
  abstract  = {A search for heavy resonances decaying into a Higgs boson (H) and a new particle (X) is reported, utilizing 36.1 fb(-1) of proton-proton collision data at root s = 13 TeV collected during 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider. The particle Xis assumed to decay to a pair of light quarks, and the fully hadronic final state XH -> q (q) over bar 'b (b) over bar is analysed. The search considers the regime of high XH resonance masses, where the X and H bosons are both highly Lorentz-boosted and are each reconstructed using a single jet with large radius parameter. A two-dimensional phase space of XH mass versus X mass is scanned for evidence of a signal, over a range of XH resonance mass values between 1 TeV and 4 TeV, and for X particles with masses from 50 GeV to 1000 GeV. All search results are consistent with the expectations for the background due to Standard Model processes, and 95\% CL upper limits are set, as a function of XH and X masses, on the production cross-section of the XH -> q (q) over bar 'b (b) over bar resonance. (c) 2018 The Author(s). Published by Elsevier B.V.},
  language  = {en}
}
@article{OPUS4-22594,
  title     = {Search for an invisibly decaying Higgs boson or dark matter candidates produced in association with a Z boson in \({pp}\) collisions at root s=13 TeV with the ATLAS detector},
  series = {Physics Letters B},
  volume    = {776},
  journal   = {Physics Letters B},
  number    = {1},
  organization    = {The ATLAS Collaboration},
  doi       = {10.1016/j.physletb.2017.11.049},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-225947},
  pages     = {318-337},
  year      = {2018},
  abstract  = {A search for an invisibly decaying Higgs boson or dark matter candidates produced in association with a leptonically decaying Z boson in proton-proton collisions at root s = 13 TeV is presented. This search uses 36.1 fb(-1) of data collected by the ATLAS experiment at the Large Hadron Collider. No significant deviation from the expectation of the Standard Model backgrounds is observed. Assuming the Standard Model ZH production cross-section, an observed (expected) upper limit of 67\% (39\%) at the 95\% confidence level is set on the branching ratio of invisible decays of the Higgs boson with mass m(H) = 125 GeV. The corresponding limits on the production cross-section of the ZH process with the invisible Higgs boson decays are also presented. Furthermore, exclusion limits on the dark matter candidate and mediator masses are reported in the framework of simplified dark matter models. (c) 2017 The Author(s). Published by Elsevier B.V.},
  language  = {en}
}