Inclusive and differential cross-section measurements of t\bartZ production in pp collisions at √s=13 TeV with the ATLAS detector, including EFT and spin-correlation interpretations

The ATLAS Collaboration, et al. (2023) Inclusive and differential cross-section measurements of t\bartZ production in pp collisions at √s=13 TeV with the ATLAS detector, including EFT and spin-correlation interpretations. arXiv, (doi: 10.48550/arXiv.2312.04450) (Unpublished)

Abstract

Measurements of both the inclusive and differential production cross sections of a top-quark-top-antiquark pair in association with a Z boson (tt¯Z) 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 σtt¯Z=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 tt¯Z 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 tt¯Z 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.

• Item Type: Articles
• Status: Unpublished
• Refereed: No
• Glasgow Author(s) Enlighten ID: Robson, Professor Aidan and Warrack, Neil and Howarth, Dr James and Mince, Mr Laurynas and Borbely, Mr Albert and Watton, Mr Elliot and Blue, Dr Andrew and Procter, Mr Tomasz and Doyle, Professor Anthony and Bates, Dr Richard and Callea, Dr Giuseppe and Simpson, Mr Ethan and Buckley, Professor Andy and Connelly, Dr Ian and O'Shea, Professor Val and Owen, Professor Mark and Watson, Ms Harriet and Spiteri, Dr Dwayne and Friend, Mr Johnny and Jamieson, Dr Jonathan and Cunningham, Dr Liam and Bussey, Dr Peter and Fabbri, Dr Federica and Buttar, Professor Craig and Wraight, Dr Kenneth and Britton, Professor David and Rozario, Mr Zefran and Fenton, Mr Michael
• Authors: The ATLAS Collaboration, , Bates, R. L., Blue, A., Borbely, A., Britton, D., Buckley, A. G., Bussey, P. J., Buttar, C. M., Callea, G., Connelly, I. A., Cunningham, W. R., Doyle, A. T., Fabbri, F., Fenton, M. J., Friend, J., Howarth, J., Jamieson, J., Mince, L., O'Shea, V., Owen, M., Procter, T., Robson, A., Rozario, Z. M.A., Simpson, E. L., Spiteri, D. P., Warrack, N., Watson, H., Watton, E., and Wraight, K.
• College/School: College of Science and Engineering; College of Science and Engineering > School of Physics and Astronomy
• Journal Name: arXiv
• Copyright Holders: Copyright © 2023 CERN for the benefit of the ATLAS Collaboration
• Publisher Policy: Reproduced under a Creative Commons License

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