Measurement of τ polarisation in Z/γ∗→ττ decays in proton–proton collisions at √s=8 TeV with the ATLAS detector

Barton, Adam Edward and Beattie, Michael and Bertram, Iain Alexander and Borissov, Guennadi and Bouhova-Thacker, Evelina Vassileva and Fox, Harald and Grimm, Kathryn Ann Tschann and Henderson, Robert Charles William and Jones, Roger William Lewis and Kartvelishvili, Vakhtang and Long, Robin Eamonn and Love, Peter Allan and Muenstermann, Daniel Matthias Alfred and Parker, Adam Jackson and Skinner, Malcolm and Smizanska, Maria and Walder, James William and Wharton, Andy and Whitmore, Ben (2018) Measurement of τ polarisation in Z/γ∗→ττ decays in proton–proton collisions at √s=8 TeV with the ATLAS detector. European Physical Journal C: Particles and Fields, 78 (2). ISSN 1434-6044

Full text not available from this repository.

Abstract

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.

Item Type:
Journal Article
Journal or Publication Title:
European Physical Journal C: Particles and Fields
Additional Information:
EPJC is an open-access journal funded by SCOAP3 and licensed under CC BY 4.0
Uncontrolled Keywords:
/dk/atira/pure/subjectarea/asjc/2200/2201
Subjects:
ID Code:
124152
Deposited By:
Deposited On:
21 Mar 2018 11:04
Refereed?:
Yes
Published?:
Published
Last Modified:
24 Mar 2020 07:38