Yazar "Aad, G" seçeneğine göre listele

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  • Küçük Resim
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    Measurement of 𝑡-channel single-top-quark production in 𝑝𝑝 collisions at √𝑠 = 5.02 TeV with the ATLAS detector
    (Elsevier B.V., 2024) Aad, G; Abbott, B; Abeling, K.; Beddall, Andrew John; Çetin, Serkant Ali; Öztürk, Sertaç; Şimşek, Sinem
    The observation of the electroweak production of single-top-quarks is made using 255 pb−1 of proton-proton collision data recorded at s=5.02 TeV with the ATLAS detector at the Large Hadron Collider. An event selection is used to identify single-top-quark candidates arising from t-channel production with the top quark decaying semi-leptonically. Events passing the selection are then used to measure the inclusive cross-section for the combined production of single-top-quarks and antiquarks, σ(tq+t¯q), and the ratio Rt between these two. They are measured to be σ(tq+t¯q)=27.1−4.1 +4.4(stat.)−3.7 +4.4(syst.) pb and Rt=2.73−0.82 +1.43(stat.)−0.29 +1.01(syst.). The individual single-top-quark (tq) and single-top-antiquark (t¯q) production cross-sections are measured to be σ(tq)=19.8−3.1 +3.9(stat.)−2.2 +2.9(syst.) pb and σ(t¯q)=7.3−2.1 +3.2(stat.)−1.5 +2.8(syst.) pb. All measurements are in good agreement with the Standard Model predictions. © 2024 The Author(s)
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    Search for neutral long-lived particles in pp collisions at ?s = 13 TeV that decay into displaced hadronic jets in the ATLAS calorimeter
    (Springer, 2022) Çetin, Serkant Ali; Beddall, Andrew John; Celebi, E.; Aad, G; Abbott, D.C.; Aboulhorma, A.; Abramowicz, H.; Abreu, H.; Bella, G.; Beloborodov, K.; Beretta, M.; Chan, W.S.; Chen, C.; Kolcu, Onur Buğra
    A search for decays of pair-produced neutral long-lived particles (LLPs) is presented using 139 fb?1 of proton-proton collision data collected by the ATLAS detector at the LHC in 2015–2018 at a centre-of-mass energy of 13 TeV. Dedicated techniques were developed for the reconstruction of displaced jets produced by LLPs decaying hadronically in the ATLAS hadronic calorimeter. Two search regions are defined for different LLP kinematic regimes. The observed numbers of events are consistent with the expected background, and limits for several benchmark signals are determined. For a SM Higgs boson with a mass of 125 GeV, branching ratios above 10% are excluded at 95% confidence level for values of c times LLP mean proper lifetime in the range between 20 mm and 10 m depending on the model. Upper limits are also set on the cross-section times branching ratio for scalars with a mass of 60 GeV and for masses between 200 GeV and 1 TeV. [Figure not available: see fulltext.] © 2022, The Author(s).