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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Measurements of Zγ and Zγγ production in pp collisions at √s=8 TeV with the ATLAS detector
AU - Barton, Adam Edward
AU - Beattie, Michael
AU - Bertram, Iain Alexander
AU - Borissov, Guennadi
AU - Bouhova-Thacker, Evelina Vassileva
AU - Cheatham, Sue
AU - Dearnaley, William
AU - Fox, Harald
AU - Grimm, Kathryn Ann Tschann
AU - Henderson, Robert Charles William
AU - Hughes, Gareth
AU - Jones, Roger William Lewis
AU - Kartvelishvili, Vakhtang
AU - Long, Robin Eamonn
AU - Love, Peter Allan
AU - Muenstermann, Daniel Matthias Alfred
AU - Parker, Adam Jackson
AU - Skinner, Malcolm
AU - Smizanska, Maria
AU - Walder, James William
AU - Wharton, Andy
AU - The ATLAS collaboration
PY - 2016/6/2
Y1 - 2016/6/2
N2 - The production of Z bosons with one or two isolated high-energy photons is studied using pp collisions at √s=8 TeV. The analyses use a data sample with an integrated luminosity of 20.3 fb−1 collected by the ATLAS detector during the 2012 LHC data taking. The Zγ and Zγγ production cross sections are measured with leptonic (e+e−, μ+μ−, νν¯) decays of the Z boson, in extended fiducial regions defined in terms of the lepton and photon acceptance. They are then compared to cross-section predictions from the Standard Model, where the sources of the photons are radiation off initial-state quarks and radiative Z-boson decay to charged leptons, and from fragmentation of final-state quarks and gluons into photons. The yields of events with photon transverse energy ET>250 GeV from ℓ+ℓ−γ events and with ET>400 GeVfrom νν¯γ events are used to search for anomalous triple gauge-boson couplings ZZγ and Zγγ. The yields of events with diphoton invariant mass mγγ>200 GeV from ℓ+ℓ−γγ events and with mγγ>300 GeV from νν¯γγevents are used to search for anomalous quartic gauge-boson couplings ZZγγand Zγγγ. No deviations from Standard Model predictions are observed and limits are placed on parameters used to describe anomalous triple and quartic gauge-boson couplings.
AB - The production of Z bosons with one or two isolated high-energy photons is studied using pp collisions at √s=8 TeV. The analyses use a data sample with an integrated luminosity of 20.3 fb−1 collected by the ATLAS detector during the 2012 LHC data taking. The Zγ and Zγγ production cross sections are measured with leptonic (e+e−, μ+μ−, νν¯) decays of the Z boson, in extended fiducial regions defined in terms of the lepton and photon acceptance. They are then compared to cross-section predictions from the Standard Model, where the sources of the photons are radiation off initial-state quarks and radiative Z-boson decay to charged leptons, and from fragmentation of final-state quarks and gluons into photons. The yields of events with photon transverse energy ET>250 GeV from ℓ+ℓ−γ events and with ET>400 GeVfrom νν¯γ events are used to search for anomalous triple gauge-boson couplings ZZγ and Zγγ. The yields of events with diphoton invariant mass mγγ>200 GeV from ℓ+ℓ−γγ events and with mγγ>300 GeV from νν¯γγevents are used to search for anomalous quartic gauge-boson couplings ZZγγand Zγγγ. No deviations from Standard Model predictions are observed and limits are placed on parameters used to describe anomalous triple and quartic gauge-boson couplings.
U2 - 10.1103/PhysRevD.93.112002
DO - 10.1103/PhysRevD.93.112002
M3 - Journal article
VL - 93
JO - Physical Review D
JF - Physical Review D
SN - 1550-7998
IS - 11
M1 - 112002
ER -