@misc{10481/85138,
year = {2022},
month = {8},
url = {https://hdl.handle.net/10481/85138},
abstract = {This letter documents a search for flavour-changing neutral currents (FCNCs), which are strongly sup-pressed in the Standard Model, in events with a photon and a top quark with the ATLAS detector. The analysis uses data collected in ppcollisions at √s=13TeV during Run2 of the LHC, corresponding to an integrated luminosity of 139fb−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 ex-cess 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. The 95% CL bounds on the branching fractions for the FCNC top-quark decays, estimated (expected) from both top-quark production and decay, are B(t→uγ) <0.85 (0.88+0.37−0.25) ×10−5and B(t→cγ) <4.2 (3.40+1.35−0.95) ×10−5for a left-handed tqγcou-pling, and B(t→uγ) <1.2 (1.20+0.50−0.33) ×10−5and B(t→cγ) <4.5 (3.70+1.47−1.03) ×10−5for a right-handed coupling.},
organization = {CERN},
organization = {ANPCyT},
organization = {YerPhI, Armenia},
organization = {Australian Research Council},
organization = {BMWFW, Austria},
organization = {Austrian Science Fund (FWF)},
organization = {Azerbaijan National Academy of Sciences (ANAS)},
organization = {Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPQ)},
organization = {Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)},
organization = {Natural Sciences and Engineering Research Council of Canada (NSERC)},
organization = {NRC, Canada},
organization = {Canada Foundation for Innovation},
organization = {ANID, Chile},
organization = {Chinese Academy of Sciences},
organization = {Ministry of Science and Technology, China},
organization = {National Natural Science Foundation of China (NSFC)},
organization = {Minciencias, Colombia},
organization = {MEYS CR, Czech Republic},
organization = {National Research Foundation of Korea},
organization = {Danish Natural Science Research Council},
organization = {Centre National de la Recherche Scientifique (CNRS)},
organization = {CEA-DRF/IRFU, France},
organization = {SRNSFG, Georgia},
organization = {Federal Ministry of Education & Research (BMBF)},
organization = {HGF, Germany},
organization = {Max Planck Society},
organization = {GSRI, Greece},
organization = {RGC, China},
organization = {Hong Kong SAR, China},
organization = {Israel Science Foundation},
organization = {Benoziyo Center, Israel},
organization = {Istituto Nazionale di Fisica Nucleare (INFN)},
organization = {Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT)},
organization = {Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT)
Japan Society for the Promotion of Science},
organization = {CNRST, Morocco},
organization = {Netherlands Organization for Scientific Research (NWO)
Netherlands Government},
organization = {RCN, Norway},
organization = {MEiN, Poland},
organization = {Fundacao para a Ciencia e a Tecnologia (FCT)},
organization = {MNE/IFA, Romania},
organization = {Ministry of Education, Science & Technological Development, Serbia},
organization = {MSSR, Slovakia},
organization = {Slovenian Research Agency - Slovenia},
organization = {MIZS, Slovenia},
organization = {DSI/NRF, South Africa},
organization = {Spanish Government},
organization = {SRC, Sweden},
organization = {Wallenberg Foundation, Sweden},
organization = {SERI, Switzerland},
organization = {Swiss National Science Foundation (SNSF)},
organization = {Canton of Bern, Switzerland},
organization = {Canton of Geneva, Switzerland},
organization = {Ministry of Science and Technology, Taiwan},
organization = {TENMAK, Tuerkiye},
organization = {UK Research & Innovation (UKRI)
Science & Technology Facilities Council (STFC)},
organization = {United States Department of Energy (DOE)},
organization = {National Science Foundation (NSF)},
organization = {BCKDF, Canada},
organization = {Canarie, Canada},
organization = {Compute Canada, Canada},
organization = {CRC, Canada},
organization = {PRIMUS, Czech Republic},
organization = {COST, European Union},
organization = {European Union (EU)
European Research Council (ERC)},
organization = {European Union (EU)
Marie Curie Actions},
organization = {Horizon 2020, European Union},
organization = {European Union (EU)
Marie Curie Actions},
organization = {Agence Nationale de la Recherche (ANR)},
organization = {German Research Foundation (DFG)},
organization = {Alexander von Humboldt Foundation},
organization = {Herakleitos, programme},
organization = {Thales Group},
organization = {Aristeia programme},
organization = {EU-ESF, Greece},
organization = {Greek NSRF, Greece},
organization = {BSF-NSF, Israel},
organization = {MINERVA, Israel},
organization = {Norwegian Financial Mechanism 2014-2021, Norway},
organization = {NCN, Poland},
organization = {Polish National Agency for Academic Exchange (NAWA)},
organization = {La Caixa Foundation},
organization = {CERCA Programme Generalitat de Catalunya, Spain},
organization = {PROMETEO Programme Generalitat Valenciana, Spain},
organization = {GenT Programme Generalitat Valenciana, Spain},
organization = {Goeran Gustafssons Stiftelser, Sweden},
organization = {Royal Society},
organization = {Leverhulme Trust		
21/SCI/017
UNCE SCI/013},
publisher = {Elsevier},
title = {Search for flavour-changing neutral-current couplings between the top quark and the photon with the ATLAS detector at √s=13TeV},
doi = {10.1016/j.physletb.2022.137379},
author = {Atlas Collaboration},
}