The European Physical Journal C > 2019 > 79 > 6 > 1-34
Measurement of $$W^{\pm }Z$$ W±Z production cross sections and gauge boson polarisation in pp collisions at $$\sqrt{s} = 13~\text {TeV}$$ s=13TeV with the ATLAS detector
Source
Abstract
This paper presents measurements of $$W^{\pm }Z$$ W±Z production cross sections in pp collisions at a centre-of-mass energy of 13 $$\text {TeV}$$ TeV . The data were collected in 2015 and 2016 by the ATLAS experiment at the Large Hadron Collider, and correspond to an integrated luminosity of $$36.1~\hbox {fb}^{-1}$$ 36.1fb-1 . The $$W^{\pm }Z$$ W±Z candidate events are reconstructed using leptonic decay modes of the gauge bosons into electrons and muons. The measured inclusive cross section in the detector fiducial region for a single leptonic decay mode is $$\sigma _{W^\pm Z \rightarrow \ell ^{'} \nu \ell \ell }^{\text {fid.}} = 63.7 \, \pm ~1.0~\text {(stat.)} \, \pm ~2.3~\text {(syst.)} \, \pm ~1.4~\text {(lumi.)}$$ σW±Z→ℓ′νℓℓfid.=63.7±1.0(stat.)±2.3(syst.)±1.4(lumi.) fb, reproduced by the next-to-next-to-leading-order Standard Model prediction of $$61.5^{+1.4}_{-1.3}$$ 61.5-1.3+1.4 fb. Cross sections for $$W^+Z$$ W+Z and $$W^-Z$$ W-Z production and their ratio are presented as well as differential cross sections for several kinematic observables. An analysis of angular distributions of leptons from decays of W and Z bosons is performed for the first time in pair-produced events in hadronic collisions, and integrated helicity fractions in the detector fiducial region are measured for the W and Z bosons separately. Of particular interest, the longitudinal helicity fraction of pair-produced vector bosons is also measured.
Identifiers
journal ISSN : | 1434-6044 |
journal e-ISSN : | 1434-6052 |
DOI | 10.1140/epjc/s10052-019-7027-6 |
Authors
O. Abdinov
- University of Adelaide, Department of Physics, Adelaide, Australia
- Azerbaijan Academy of Sciences, Institute of Physics, Baku, Azerbaijan