Measurement of tau polarisation in Z/gamma* -> tau tau decays in proton-proton collisions at root s=8 TeV with the ATLAS detector



Aaboudd, M, Aad, G, Abbott, B, Abdinov, O, Abeloos, B, Abidi, SH, AbouZeid, OS, Abraham, NL, Abrainowicz, H, Abreu, H
et al (show 2886 more authors) (2018) Measurement of tau polarisation in Z/gamma* -> tau tau decays in proton-proton collisions at root s=8 TeV with the ATLAS detector. EUROPEAN PHYSICAL JOURNAL C, 78 (2). 163-.

Access the full-text of this item by clicking on the Open Access link.
[img] Text
1709.03490v2.pdf - Submitted version

Download (670kB)

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: Article
Additional Information: 44 pages in total, author list starting page 28, 6 figures, 7 tables, submitted to EPJC. Al l figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2015-18
Uncontrolled Keywords: ATLAS Collaboration
Depositing User: Symplectic Admin
Date Deposited: 10 Apr 2018 09:30
Last Modified: 19 Jan 2023 06:37
DOI: 10.1140/epjc/s10052-018-5619-1
Open Access URL: http://10.0.4.116/epjc/s10052-018-5619-1
Related URLs:
URI: https://livrepository.liverpool.ac.uk/id/eprint/3019640