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SMEFT effects on spin correlations and entanglement at NLO QCD in diboson production at hadron colliders

Giovanni Pelliccioli* and Emanuele Re†

  • *Contact author: giovanni.pelliccioli@unimib.it
  • †Contact author: emanuele.re@mib.infn.it
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Phys. Rev. D 113, 093005 – Published 28 May, 2026

DOI: https://doi.org/10.1103/mr8r-bvcd

Abstract

We perform for the first time a full study of spin correlations in inclusive production of WZ boson pairs at the LHC with leptonic decays in the presence of next-to-leading-order QCD corrections and of effects from a dimension-six operator in the Standard-Model effective field theory (SMEFT) modifying the electroweak triple-gauge coupling. We carry out the complete quantum-state tomography of the diboson system and relate its results to common purity and spin-entanglement markers, highlighting the sizeable impact of both QCD corrections and SMEFT insertions. Additionally, we show how a naïve truncation at dimension six in the SMEFT expansion of the spin-density matrix can lead to a cumbersome spin interpretation of the quantum-tomography results.

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Phys. Rev. D 113, 093005– Published 28 May, 2026
  • Received 28 January 2026
  • Accepted 28 April 2026
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