Please use this identifier to cite or link to this item:
|Title:||Test of the universality of tau and mu lepton couplings in W-boson decays with the ATLAS detector||Authors:||Aad, G.
Abbott, D. C.
Abud, A. Abed
Abhayasinghe, D. K.
The ATLAS Collaboration
|Issue Date:||2021||Publisher:||Nature Research||Abstract:||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 t leptons and muons, R(tau/mu), constitutes an important test of this axiom. Using 139 fb(-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 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 t lepton through the muon transverse impact parameter and differences in the muon transverse momentum spectra. The measured value of R(tau/mu) is 0.992 +/- 0.013 [+/- 0.007(stat) +/- 0.011(syst)] and is in agreement with the hypothesis of universal lepton couplings as postulated in the standard model. This is the only such measurement from the Large Hadron Collider, so far, and obtains twice the precision of previous measurements.||URI:||https://doi.org/10.1038/s41567-021-01236-w
|Appears in Collections:||Malzeme Bilimi ve Nanoteknoloji Mühendisliği Bölümü / Department of Material Science & Nanotechnology Engineering|
Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
WoS İndeksli Yayınlar Koleksiyonu / WoS Indexed Publications Collection
Show full item record
checked on Sep 23, 2022
WEB OF SCIENCETM
checked on Sep 24, 2022
checked on Dec 26, 2022
Items in GCRIS Repository are protected by copyright, with all rights reserved, unless otherwise indicated.