Search for flavour-changing neutral-current couplings between the top quark and the photon with the ATLAS detector at √s=13 TeV

0578320 - FZÚ 2024 RIV NL eng J - Journal Article
Aad, G. - Abbott, B. - Abbott, D.C. - Chudoba, Jiří - Hejbal, Jiří - 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 2897 authors
Search for flavour-changing neutral-current couplings between the top quark and the photon with the ATLAS detector at √s=13 TeV.
Physics Letters. B. Roč. 842, July (2023), č. článku 137379. ISSN 0370-2693. E-ISSN 1873-2445
Research Infrastructure: CERN-CZ III - 90240
Institutional support: RVO:68378271
Keywords : pp: colliding beams * neutral current: flavor changing * top: pair production
OECD category: Particles and field physics
Impact factor: 4.3, year: 2022
Method of publishing: Open access

This letter documents a search for flavour-changing neutral currents (FCNCs), which are strongly suppressed in the Standard Model, in events with a photon and a top quark with the ATLAS detector. The analysis uses data collected in pp collisions at √s=13 TeV during Run 2 of the LHC, corresponding to an integrated luminosity of 139 fb−1. Both FCNC top-quark production and decay are considered. The final state consists of a charged lepton, missing transverse momentum, a b-tagged jet, one high-momentum photon and possibly additional jets. A multiclass deep neural network is used to classify events either as signal in one of the two categories, FCNC production or decay, or as background. No significant excess of events over the background prediction is observed and 95% CL upper limits are placed on the strength of left- and right-handed FCNC interactions.
Permanent Link: https://hdl.handle.net/11104/0347334