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

0499975 - FZÚ 2019 RIV DE eng J - Journal Article
Aaboud, M. - Aad, G. - Abbott, B. - Chudoba, Jiří - Hejbal, Jiří - Hladík, Ondřej - Jakoubek, Tomáš - Kepka, Oldřich - Kroll, Jiří - Kupčo, Alexander - Lokajíček, Miloš - Lysák, Roman - Marčišovský, Michal - Mikeštíková, Marcela - Němeček, Stanislav - Penc, Ondřej - Šícho, Petr - Staroba, Pavel - Svatoš, Michal - Taševský, Marek … Total 2895 authors
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. Roč. 78, č. 2 (2018), s. 1-30, č. článku 163. ISSN 1434-6044. E-ISSN 1434-6052
R&D Projects: GA MŠMT(CZ) LTT17018
Institutional support: RVO:68378271
Keywords : ATLAS * CERN LHC Coll * numerical calculations: Monte Carlo * phase space * kinematics * PYTHIA * experimental results * 8000 GeV-cms
OECD category: Particles and field physics
Impact factor: 4.843, year: 2018

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)

Permanent Link: http://hdl.handle.net/11104/0292155