Predicting ttZ spin correlations at the LHC

My paper on spin correlations in \(t\bar{t}Z\) production has been published in the European Physical Journal C. This phenomenological study laid the groundwork for the first experimental measurement of this quantum effect.

In this paper, we computed the full spin density matrix for \(t\bar{t}Z\) production at NLO in QCD and found that the additional \(Z\) boson emission leads to significantly different spin correlations compared to the more familiar \(t\bar{t}\) case.

We also showed that the angular information in the spin density matrix provides novel constraints on dimension-6 EFT operators — constraints that are independent of the total production rate.

The experimental measurement followed two years later in our legacy ttZ paper, confirming the prediction.

Links: arXiv:2106.09690 · DOI