Test of the universality of τ and μ lepton couplings in W-boson decays with the ATLAS detector

0548599 - FZÚ 2022 RIV GB eng J - Journal Article
Aad, G. - Abbott, B. - Abbott, D.C. - Chudoba, Jiří - Hejbal, Jiří - Hladík, Ondřej - Jačka, Petr - Kepka, Oldřich - Kroll, Jiří - Kupčo, Alexander - Latoňová, Věra - Lokajíček, Miloš - Lysák, Roman - Marčišovský, Michal - Mikeštíková, Marcela - Němeček, Stanislav - Penc, Ondřej - Šícho, Petr - Staroba, Pavel - Svatoš, Michal - Taševský, Marek … Total 2937 authors
Test of the universality of τ and μ lepton couplings in W-boson decays with the ATLAS detector.
Nature Physics. Roč. 17, č. 7 (2021), s. 813-818. ISSN 1745-2473. E-ISSN 1745-2481
R&D Projects: GA MŠMT(CZ) LTT17018
Research Infrastructure: CERN-CZ II - 90104
Institutional support: RVO:68378271
Keywords : ATLAS * final state: ((n)jet dilepton) * transverse momentum: momentum spectrum
OECD category: Particles and field physics
Impact factor: 19.684, year: 2021
Method of publishing: Open access

The standard model of particle physics encapsulates our best current understanding of physics at the smallest scales. A fundamental axiom of this theory is the universality of the couplings of the different generations of leptons to the electroweak gauge bosons. The measurement of the ratio of the decay rate of W bosons to τ leptons and muons, R(τ/μ), constitutes an important test of this axiom. Using 139 fb−1^{−1}−1 of proton–proton collisions recorded with the ATLAS detector at a centre-of-mass energy of 13 TeV, we report a measurement of this quantity from di-leptonic tt‾toverline{t}tt events where the top quarks decay into a W boson and a bottom quark. We can distinguish muons originating from W bosons and those originating from an intermediate τ lepton through the muon transverse impact parameter and differences in the muon transverse momentum spectra.
Permanent Link: http://hdl.handle.net/11104/0324647