Search for lepton-flavor violation in Z-boson decays with tau leptons with the ATLAS detector.

0552879 - FZÚ 2022 RIV US 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 2881 authors
Search for lepton-flavor violation in Z-boson decays with tau leptons with the ATLAS detector.
Physical Review Letters. Roč. 127, č. 27 (2021), č. článku 271801. ISSN 0031-9007. E-ISSN 1079-7114
R&D Projects: GA MŠk(CZ) LTT17018
Research Infrastructure: CERN-CZ II - 90104
Institutional support: RVO:68378271
Keywords : ATLAS * CERN LHC Coll * Z0: branching ratio: upper limit * sensitivity
OECD category: Particles and field physics
Impact factor: 9.185, year: 2021
Method of publishing: Open access

A search for lepton-flavor-violating Z→eτZ o e auZ→eτ and Z→μτZ omu auZ→μτ decays with pppppp collision data recorded by the ATLAS detector at the LHC is presented. This analysis uses 139 fb−1^{-1}−1 of Run 2 pppppp collisions at s=13sqrt{s}=13s ​=13 TeV and is combined with the results of a similar ATLAS search in the final state in which the τ auτ-lepton decays hadronically, using the same data set as well as Run 1 data. The addition of leptonically decaying τ auτ-leptons significantly improves the sensitivity reach for Z→ℓτZ oell auZ→ℓτ decays. The Z→ℓτZ oell auZ→ℓτ branching fractions are constrained in this analysis to B(Z→eτ)<7.0×10−6mathcal{B}(Z o e au)<7.0 imes10^{-6}B(Z→eτ)<7.0×10−6 and B(Z→μτ)<7.2×10−6mathcal{B}(Z o mu au)<7.2 imes10^{-6}B(Z→μτ)<7.2×10−6 at 95% confidence level.
Permanent Link: http://hdl.handle.net/11104/0328232