Measurement of t t ¯ production in association with additional b -jets in the eμ final state in proton–proton collisions at s = 13 TeV with the ATLAS detector

Journal article

This paper presents measurements of top-antitop quark pair (tt¯) production in association with additional b-jets. The analysis utilises 140 fb−1 of proton–proton collision data collected with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 13 TeV. Fiducial cross-sections are extracted in a final state featuring one electron and one muon, with at least three or four b-jets. Results are presented at the particle level for both integrated cross-sections and normalised differential cross-sections, as functions of global event properties, jet kinematics, and b-jet pair properties. Observable quantities characterising b-jets originating from the top quark decay and additional b-jets are also measured at the particle level, after correcting for detector effects. The measured integrated fiducial cross-sections are consistent with tt¯bb¯ predictions from various next-to-leading-order matrix element calculations matched to a parton shower within the uncertainties of the predictions. State-of-the-art theoretical predictions are compared with the differential measurements; none of them simultaneously describes all observables. Differences between any two predictions are smaller than the measurement uncertainties for most observables.

Authors: Aad, G; Aakvaag, E; Abbott, B; Abdelhameed, S; Abeling, K

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Springer
• Journal: Journal of High Energy Physics
• Volume: 2025
• Issue: 1
• Article number: 68
• Publication date: 2025-01-14
• Acceptance date: 2024-11-21
• DOI: 10.1007/jhep01(2025)068
• EISSN: 1029-8479
• ISSN: 1126-6708
• Language: English
• Keywords: Hadron-Hadron Scattering; Top Physics