Examinando por Autor "AbouZeid, O.S"

Mostrando 1 - 2 de 2
  • Miniatura
    Ítem
    Measurement of isolated-photon plus two-jet production in pp collisions at p s = 13TeV with the ATLAS detector
    (Springer, 2020-03) Aad, G.; Abbott, B.; Abbott, D.C.; Abed Abud, A.; Abeling ., K; Abhayasinghe, D.K; Abidi, S.H; AbouZeid, O.S; Abraham, N.L; Abramowicz, H; Abreu, H; Abulaiti, Y
    The dynamics of isolated-photon plus two-jet production in "padding-size-4-x display--inline-block" style="background: var(--highlight-yellow); color: inherit;">pp collisions at a centre-of-mass energy of 13 TeV are studied with the ATLAS detector at the LHC using a dataset corresponding to an integrated luminosity of 36.1 fb−1. Cross sections are measured as functions of a variety of observables, including angular correlations and invariant masses of the objects in the final state, γ + jet + jet. Measurements are also performed in phase-space regions enriched in each of the two underlying physical mechanisms, namely direct and fragmentation processes. The measurements cover the range of photon (jet) transverse momenta from 150 GeV (100 GeV) to 2 TeV. The tree-level plus parton-shower predictions from Sherpa and Pythia as well as the next-to-leading-order QCD predictions from Sherpa are compared with the measurements. The next-to-leading-order QCD predictions describe the data adequately in shape and normalisation except for regions of phase space such as those with high values of the invariant mass or rapidity separation of the two jets, where the predictions overestimate the data. [Figure not available: see fulltext.] © 2020, The Author(s).
  • Miniatura
    Ítem
    Search for new resonances in mass distributions of jet pairs using 139 fb −1 of pp collisions at √s = 13 TeV with the ATLAS detector
    (Springer, 2020-03) Aad, G.; Abbott, B.; Abbott, D.C; Abed Abud, A.; Abeling, K.; Abhayasinghe, D.K.; Abidi, S.H.; AbouZeid, O.S; Abraham ., N.L; Abramowicz, H; Abreu, H; Abulaiti, Y.
    A search for new resonances decaying into a pair of jets is reported using the dataset of proton-proton collisions recorded at s = 13 TeV with the ATLAS detector at the Large Hadron Collider between 2015 and 2018, corresponding to an integrated luminosity of 139 fb−1. The distribution of the invariant mass of the two leading jets is examined for local excesses above a data-derived estimate of the Standard Model background. In addition to an inclusive dijet search, events with jets identified as containing b-hadrons are examined specifically. No significant excess of events above the smoothly falling background spectra is observed. The results are used to set cross-section upper limits at 95% confidence level on a range of new physics scenarios. Model-independent limits on Gaussian-shaped signals are also reported. The analysis looking at jets containing b-hadrons benefits from improvements in the jet flavour identification at high transverse momentum, which increases its sensitivity relative to the previous analysis beyond that expected from the higher integrated luminosity. [Figure not available: see fulltext.] © 2020, The Author(s).