On two-body and three-body spin correlations in leptonic $$ t\overline{t}Z $$ production and anomalous couplings at the LHC

Abstract

Abstract We study the anomalous $$ t\overline{t}Z $$ t t ¯ Z couplings in the $$ t\overline{t}Z $$ t t ¯ Z production in leptonic final state at the 13 TeV LHC. We use the polarizations of top quarks and Z boson, two-body and three-body spin correlations among the top quarks and Z boson, and the cross section to probe the anomalous couplings. We estimate one parameter and simultaneous limits on the couplings of the effective vertex as well as the effective operators for a set of luminosities 150 fb−1, 300 fb−1, 1000 fb−1, and 3000 fb−1. The polarizations and the spin correlations are found to be helpful on top of the cross section to better constrain the anomalous couplings.