Rimoldi, Marco; Mullier, Geoffrey; Miucci, Antonio; Merlassino, Claudia; Haug, Sigve; Weber, Michael; Meloni, Federico; Beck, Hans Peter; Ereditato, Antonio (2018). Search for flavour-changing neutral current top-quark decays t → qZ in proton-proton collisions at √s=13 TeV with the ATLAS detector. Journal of High Energy Physics, 2018(7) Springer 10.1007/JHEP07(2018)176
|
Text
Aaboud2018_Article_SearchForFlavour-changingNeuTr.pdf - Published Version Available under License Creative Commons: Attribution (CC-BY). Download (1MB) | Preview |
A search for flavour-changing neutral-current processes in top-quark decays is presented. Data collected with the ATLAS detector from proton-proton collisions at the Large Hadron Collider at a centre-of-mass energy of √s = 13 TeV, corresponding to an integrated luminosity of 36.1 fb⁻¹, are analysed. The search is performed using topquark pair events, with one top quark decaying through the t → qZ (q = u, c) flavour-changing neutral-current channel, and the other through the dominant Standard Model mode t → bW. Only Z boson decays into charged leptons and leptonic W boson decays
are considered as signal. Consequently, the final-state topology is characterized by the presence of three isolated charged leptons (electrons or muons), at least two jets, one of the jets originating from a b-quark, and missing transverse momentum from the undetected neutrino. The data are consistent with Standard Model background contributions, and at 95% confidence level the search sets observed (expected) upper limits of 1.7 x 10⁻⁴ (2.4 x 10⁻⁴) on the t → uZ branching ratio and 2.4 x 10⁻⁴ (3.2 x 10⁻⁴) on the t → cZ branching ratio, constituting the most stringent limits to date.
Item Type: |
Journal Article (Original Article) |
|---|---|
Division/Institute: |
08 Faculty of Science > Physics Institute > Laboratory for High Energy Physics (LHEP) |
UniBE Contributor: |
Haug, Sigve, Weber, Michele, Beck, Hans Peter |
Subjects: |
500 Science > 530 Physics |
ISSN: |
1029-8479 |
Publisher: |
Springer |
Language: |
English |
Submitter: |
BORIS Import LHEP |
Date Deposited: |
25 Jun 2019 13:05 |
Last Modified: |
05 Dec 2022 15:27 |
Publisher DOI: |
10.1007/JHEP07(2018)176 |
ArXiv ID: |
1803.09923 |
Additional Information: |
Kollaboration - Es sind nur die Berner Autoren namentlich erwaehnt |
BORIS DOI: |
10.7892/boris.129064 |
URI: |
https://boris.unibe.ch/id/eprint/129064 |
Actions (login required)
 |
Edit item |