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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 - Measurement of τ polarisation in Z/γ∗→ττ decays in proton–proton 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 - Fox, Harald
AU - Grimm, Kathryn Ann Tschann
AU - Henderson, Robert Charles William
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 - Whitmore, Ben
AU - The ATLAS collaboration
N1 - EPJC is an open-access journal funded by SCOAP3 and licensed under CC BY 4.0
PY - 2018/2/24
Y1 - 2018/2/24
N2 - This paper presents a measurement of the polarisation of τ leptons produced in Z/γ∗→ττ decays which is performed with a dataset of proton—proton collisions at √s=8 TeV, corresponding to an integrated luminosity of 20.2 fb−1 recorded with the ATLAS detector at the LHC in 2012. The Z/γ∗→ττ decays are reconstructed from a hadronically decaying τ lepton with a single charged particle in the final state, accompanied by a τ lepton that decays leptonically. The τ polarisation is inferred from the relative fraction of energy carried by charged and neutral hadrons in the hadronic τ decays. The polarisation is measured in a fiducial region that corresponds to the kinematic region accessible to this analysis. The τ polarisation extracted over the full phase space within the Z/γ∗ mass range of 66<mZ/γ∗< 116 GeV is found to be Pτ=−0.14±0.02(stat)±0.04(syst). It is in agreement with the Standard Model prediction of Pτ=−0.1517±0.0019, which is obtained from the ALPGEN event generator interfaced with the PYTHIA 6 parton shower modelling and the TAUOLA τ decay library.
AB - This paper presents a measurement of the polarisation of τ leptons produced in Z/γ∗→ττ decays which is performed with a dataset of proton—proton collisions at √s=8 TeV, corresponding to an integrated luminosity of 20.2 fb−1 recorded with the ATLAS detector at the LHC in 2012. The Z/γ∗→ττ decays are reconstructed from a hadronically decaying τ lepton with a single charged particle in the final state, accompanied by a τ lepton that decays leptonically. The τ polarisation is inferred from the relative fraction of energy carried by charged and neutral hadrons in the hadronic τ decays. The polarisation is measured in a fiducial region that corresponds to the kinematic region accessible to this analysis. The τ polarisation extracted over the full phase space within the Z/γ∗ mass range of 66<mZ/γ∗< 116 GeV is found to be Pτ=−0.14±0.02(stat)±0.04(syst). It is in agreement with the Standard Model prediction of Pτ=−0.1517±0.0019, which is obtained from the ALPGEN event generator interfaced with the PYTHIA 6 parton shower modelling and the TAUOLA τ decay library.
U2 - 10.1140/epjc/s10052-018-5619-1
DO - 10.1140/epjc/s10052-018-5619-1
M3 - Journal article
VL - 78
JO - European Physical Journal C: Particles and Fields
JF - European Physical Journal C: Particles and Fields
SN - 1434-6044
IS - 2
M1 - 163
ER -