Measurement of the element of the CKM matrix in decays with the ATLAS detector
Using 140 fb of 13 TeV proton-proton collision data collected by the ATLAS detector, this paper presents the first measurement of the CKM matrix element from on-shell -boson decays in top quark pairs, yielding a value of that is consistent with existing low-energy determinations while probing a novel high-momentum-transfer physical regime.