SMEFT effects on spin correlations and entanglement at NLO QCD in di-boson production at hadron colliders

TL;DR

This paper investigates how SMEFT dimension-six operators and NLO QCD corrections influence spin correlations and entanglement in WZ production at the LHC, providing a comprehensive quantum-state analysis.

Contribution

It presents the first full quantum-state tomography of the di-boson system including SMEFT effects and QCD corrections, revealing their significant impact on spin observables.

Findings

QCD corrections and SMEFT operators significantly alter spin correlations.

Naive SMEFT truncation complicates the interpretation of spin states.

Complete quantum tomography provides clearer insights into spin entanglement.

Abstract

We perform for the first time a full study of spin correlations in inclusive WZ production at the LHC with leptonic decays in the presence of NLO QCD corrections and of effects from a dimension-six operator in the SMEFT modifying the electroweak triple-gauge coupling. We carry out the complete quantum-state tomography of the di-boson 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 naive 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.