English

Observation of tWZ production at the CMS experiment

High Energy Physics - Experiment 2026-03-03 v2

Abstract

The first observation of single top quark production in association with a W and a Z boson in proton-proton collisions is reported. The analysis uses data at center-of-mass energies of 13 and 13.6 TeV recorded with the CMS detector at the CERN LHC, corresponding to a total integrated luminosity of 200 fb1^{-1}. Events with three or four charged leptons, which can be electrons or muons, are selected. Advanced machine-learning algorithms and improved reconstruction methods, compared to an earlier analysis, result in an unprecedented sensitivity to tWZ production. The measured cross sections for tWZ production are 248 ±\pm 52 fb and 242 ±\pm 77 fb for s\sqrt{s} = 13 and 13.6 TeV, respectively. The signal is established with a statistical significance of 5.8 standard deviations, with 3.5 expected, compared to the background-only hypothesis.

Keywords

Cite

@article{arxiv.2510.19080,
  title  = {Observation of tWZ production at the CMS experiment},
  author = {CMS Collaboration},
  journal= {arXiv preprint arXiv:2510.19080},
  year   = {2026}
}

Comments

Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/TOP-24-009 (CMS Public Pages)