A measurement of the top-quark pole mass m pole t is presented in tt¯ events with an additional jet, tt¯+ 1-jet, produced in pp collisions at √ s = 13 TeV. The data sample, recorded with the ATLAS experiment during Run 2 of the LHC, corresponds to an integrated luminosity of 140 fb−1 . Events with one electron and one muon of opposite electric charge in the final state are selected to measure the tt¯+ 1-jet differential cross-section as a function of the inverse of the invariant mass of the tt¯+ 1-jet system. Iterative Bayesian Unfolding is used to correct the data to enable comparison with fixed-order calculations at next-to-leading-order accuracy in the strong coupling. The process pp → ttj¯ (2 → 3), where top quarks are taken as stable particles, and the process pp → b ¯bl+νl−νj¯ (2 → 7), which includes top-quark decays to the dilepton final state and off-shell effects, are considered. The top-quark mass is extracted using a χ 2 fit of the unfolded normalized differential cross-section distribution. The results obtained with the 2 → 3 and 2 → 7 calculations are compatible within theoretical uncertainties, providing an important consistency check. The more precise determination is obtained for the 2 → 3 measurement: m pole t = 170.7±0.3 (stat.)±1.4 (syst.)±0.3 (scale)±0.2 (PDF⊕αS) GeV, which is in good agreement with other top-quark mass results.

Null, N., Aad, G., Aakvaag, E., Abbott, B., Abdelhameed, S., Abeling, K., et al. (2025). Measurement of the top-quark pole mass in dileptonic tt¯+ 1-jet events at √s = 13 TeV with the ATLAS experiment. JOURNAL OF HIGH ENERGY PHYSICS, 2025(12), 0-50 [10.1007/jhep12(2025)023].

Measurement of the top-quark pole mass in dileptonic tt¯+ 1-jet events at √s = 13 TeV with the ATLAS experiment

Alberghi, G. L.;Alfonsi, F.;Ballabene, E.;Bellagamba, L.;Bianco, G.;Boscherini, D.;Bruni, A.;Carratta, G.;Cremonini, D.;De Castro, S.;Fabbri, F.;Fabbri, L.;Franchini, M.;Gabrielli, A.;Giacobbe, B.;Lasagni Manghi, F.;Levrini, G.;Nechaeva, S.;Polini, A.;Rinaldi, L.;Romano, M.;Sanzani, E.;Sbarra, C.;Sbrizzi, A.;Semprini-Cesari, N.;Sioli, M.;Todome, K.;Valentinetti, S.;Villa, M.;Vittori, C.;Vivarelli, I.;Zoccoli, A.;
2025

Abstract

A measurement of the top-quark pole mass m pole t is presented in tt¯ events with an additional jet, tt¯+ 1-jet, produced in pp collisions at √ s = 13 TeV. The data sample, recorded with the ATLAS experiment during Run 2 of the LHC, corresponds to an integrated luminosity of 140 fb−1 . Events with one electron and one muon of opposite electric charge in the final state are selected to measure the tt¯+ 1-jet differential cross-section as a function of the inverse of the invariant mass of the tt¯+ 1-jet system. Iterative Bayesian Unfolding is used to correct the data to enable comparison with fixed-order calculations at next-to-leading-order accuracy in the strong coupling. The process pp → ttj¯ (2 → 3), where top quarks are taken as stable particles, and the process pp → b ¯bl+νl−νj¯ (2 → 7), which includes top-quark decays to the dilepton final state and off-shell effects, are considered. The top-quark mass is extracted using a χ 2 fit of the unfolded normalized differential cross-section distribution. The results obtained with the 2 → 3 and 2 → 7 calculations are compatible within theoretical uncertainties, providing an important consistency check. The more precise determination is obtained for the 2 → 3 measurement: m pole t = 170.7±0.3 (stat.)±1.4 (syst.)±0.3 (scale)±0.2 (PDF⊕αS) GeV, which is in good agreement with other top-quark mass results.
2025
Null, N., Aad, G., Aakvaag, E., Abbott, B., Abdelhameed, S., Abeling, K., et al. (2025). Measurement of the top-quark pole mass in dileptonic tt¯+ 1-jet events at √s = 13 TeV with the ATLAS experiment. JOURNAL OF HIGH ENERGY PHYSICS, 2025(12), 0-50 [10.1007/jhep12(2025)023].
Null, Null; Aad, G.; Aakvaag, E.; Abbott, B.; Abdelhameed, S.; Abeling, K.; Abicht, N. J.; Abidi, S. H.; Aboelela, M.; Aboulhorma, A.; Abramowicz, H.;...espandi
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11585/1050433
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