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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Observation of gauge boson joint-polarisation states in W±Z production from pp collisions at s=13 TeV with the ATLAS detector
AU - ATLAS Collaboration
AU - Barton, A.E.
AU - Bertram, I.A.
AU - Borissov, G.
AU - Bouhova-Thacker, E.V.
AU - Ferrando, James
AU - Fox, H.
AU - Henderson, R.C.W.
AU - Jones, R.W.L.
AU - Kartvelishvili, V.
AU - Love, P.A.
AU - Marshall, E.J.
AU - Meng, L.
AU - Muenstermann, D.
AU - Rybacki, K.
AU - Smizanska, M.
AU - Spinali, S.
AU - Wharton, A.M.
PY - 2023/8/10
Y1 - 2023/8/10
N2 - Measurements of joint-polarisation states of W and Z gauge bosons in W ±Z production are presented. The data set used corresponds to an integrated luminosity of 139 fb −1 of proton–proton collisions at a centre-of-mass energy of 13 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. The W ±Z candidate events are reconstructed using leptonic decay modes of the gauge bosons into electrons and muons. The simultaneous pair-production of longitudinally polarised vector bosons is measured for the first time with a significance of 7.1 standard deviations. The measured joint helicity fractions integrated over the fiducial region are f 00=0.067±0.010, f 0T=0.110±0.029, f T0=0.179±0.023 and f TT=0.644±0.032, in agreement with the next-to-leading-order Standard Model predictions. Individual helicity fractions of the W and Z bosons are also measured and found to be consistent with joint helicity fractions within the expected amounts of correlation. Both the joint and individual helicity fractions are also measured separately in W +Z and W −Z events. Inclusive and differential cross sections for several kinematic observables sensitive to polarisation are presented.
AB - Measurements of joint-polarisation states of W and Z gauge bosons in W ±Z production are presented. The data set used corresponds to an integrated luminosity of 139 fb −1 of proton–proton collisions at a centre-of-mass energy of 13 TeV recorded by the ATLAS detector at the CERN Large Hadron Collider. The W ±Z candidate events are reconstructed using leptonic decay modes of the gauge bosons into electrons and muons. The simultaneous pair-production of longitudinally polarised vector bosons is measured for the first time with a significance of 7.1 standard deviations. The measured joint helicity fractions integrated over the fiducial region are f 00=0.067±0.010, f 0T=0.110±0.029, f T0=0.179±0.023 and f TT=0.644±0.032, in agreement with the next-to-leading-order Standard Model predictions. Individual helicity fractions of the W and Z bosons are also measured and found to be consistent with joint helicity fractions within the expected amounts of correlation. Both the joint and individual helicity fractions are also measured separately in W +Z and W −Z events. Inclusive and differential cross sections for several kinematic observables sensitive to polarisation are presented.
U2 - 10.1016/j.physletb.2023.137895
DO - 10.1016/j.physletb.2023.137895
M3 - Journal article
VL - 843
JO - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
JF - Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
M1 - 137895
ER -