Single top-quark production in association with a Z boson, where the Z boson decays to a pair of charged leptons, is measured in the trilepton channel. The proton-proton collision data collected by the ATLAS experiment from 2015 to 2018 at a centre-of-mass energy of 13 TeV are used, corresponding to an integrated luminosity of 139 fb−1. Events containing three isolated charged leptons (electrons or muons) and two or three jets, one of which is identified as containing a b-hadron, are selected. The main backgrounds are from tt¯ Z and diboson production. Neural networks are used to improve the background rejection and extract the signal. The measured cross-section for tℓ+ℓ−q production, including non-resonant dilepton pairs with mℓ+ℓ−> 30 GeV, is 97 ± 13 (stat.) ± 7 (syst.) fb, consistent with the Standard Model prediction. [Figure not available: see fulltext.]
Observation of the associated production of a top quark and a Z boson in pp collisions at √s = 13 TeV with the ATLAS detector / Aloisio, A., Alviggi, M., Canale, V., Della Pietra, M., Merola, L., Massarotti, P., Conventi, F., Rossi, E., Carlino, G., De Asmundis, R., Di Donato, C., Doria, A., Iengo, P., Izzo, V., Perrella, S., Sekhniaidze, G., Cirotto, F., Lavorgna, M., Giannini, A., Atlas, C., et al.. - In: JOURNAL OF HIGH ENERGY PHYSICS. - ISSN 1029-8479. - 2020:7(2020). [10.1007/JHEP07(2020)124]
Observation of the associated production of a top quark and a Z boson in pp collisions at √s = 13 TeV with the ATLAS detector
Aloisio, Alberto;Alviggi, MariaGrazia;Canale, Vincenzo;Della Pietra, Massimo;Merola, Leonardo;Massarotti, Paolo;Conventi, Francesco;Rossi, Elvira;de Asmundis, Riccardo;Perrella, Sabrina;Cirotto, Francesco;Lavorgna, Marco;LOFFREDO, Salvatore
2020
Abstract
Single top-quark production in association with a Z boson, where the Z boson decays to a pair of charged leptons, is measured in the trilepton channel. The proton-proton collision data collected by the ATLAS experiment from 2015 to 2018 at a centre-of-mass energy of 13 TeV are used, corresponding to an integrated luminosity of 139 fb−1. Events containing three isolated charged leptons (electrons or muons) and two or three jets, one of which is identified as containing a b-hadron, are selected. The main backgrounds are from tt¯ Z and diboson production. Neural networks are used to improve the background rejection and extract the signal. The measured cross-section for tℓ+ℓ−q production, including non-resonant dilepton pairs with mℓ+ℓ−> 30 GeV, is 97 ± 13 (stat.) ± 7 (syst.) fb, consistent with the Standard Model prediction. [Figure not available: see fulltext.]I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
