Электронный каталог

Статья

Aad, G.
Inclusive and Differential Cross-Section Measurements of tt^-Z Production in pp Collisions at *%s=13 TeV with the ATLAS Detector, Including EFT and Spin-Correlation Interpretations / G.Aad, F.Ahmadov, I.N.Aleksandrov, V.A.Bednyakov, I.R.Boyko, G.A.Chelkov, A.Cheplakov, M.V.Chizhov, D.V.Dedovich, M.Demichev, M.I.Gostkin, S.N.Karpov, Z.M.Karpova, U.Kruchonak, V.Kukhtin, E.Ladygin, V.Lyubushkin, T.Lyubushkina, S.Malyukov, M.Mineev, E.Plotnikova, I.N.Potrap, N.A.Rusakovich, M.Shiyakova, A.Soloshenko, T.Turtuvshin, A.Vasyukov, I.Yeletskikh, A.Zhemchugov, N.I.Zimine, Y.Kulchitsky, [ATLAS Collab.] // Journal of High Energy Physics [Electronic resource]. – 2024. – Vol. 2024, No. 7. – P. 163. – URL: https://doi.org/10.1007/JHEP07(2024)163. – Bibliogr.: 120.

Measurements of both the inclusive and differential production cross sections of a top-quark-top-antiquark pair in association with a Z boson (t¯tZ) are presented. Final states with two, three or four isolated leptons (electrons or muons) are targeted. The measurements use the data recorded by the ATLAS detector in pp collisions at √s = 13 TeV at the Large Hadron Collider during the years 2015–2018, corresponding to an integrated luminosity of 140 fb−1. The inclusive cross section is measured to be σt¯tZ = 0.86±0.04 (stat.)±0.04 (syst.) pb and found to be in agreement with the most advanced Standard Model predictions. The differential measurements are presented as a function of a number of observables that probe the kinematics of the t¯tZ system. Both the absolute and normalised differential cross-section measurements are performed at particle level and parton level for specific fiducial volumes, and are compared with NLO+NNLL theoretical predictions. The results are interpreted in the framework of Standard Model effective field theory and used to set limits on a large number of dimension-6 operators involving the top quark. The first measurement of spin correlations in t¯tZ events is presented: the results are in agreement with the Standard Model expectations, and the null hypothesis of no spin correlations is disfavoured with a significance of 1.8 standard deviations.



ОИЯИ = ОИЯИ (JINR)2024
Спец.(статьи,препринты) = С 346.2в - Взаимодействие протонов с протонами
Спец.(статьи,препринты) = С 346.6д1 - Чармоний, боттомоний, топ-кварк. Очарованные частицы и др. резонансы из тяжелых кварков