Next-to-next-to-leading order event generation for Z-boson pair production matched to parton shower

• DOI: 10.1016/j.physletb.2021.136380
• Publication Date: 2021-05-21T20:50:02Z
• Authors: Simone Alioli; Alessandro Broggio; Alessandro Gavardi; Stefan Kallweit; Matthew A. Lim; Riccardo Nagar; Davide Napoletano
• Keywords: Parton shower; Massless particle; Pair production; Air shower

We present a novel next-to-next-to-leading order (NNLO) QCD calculation matched to parton shower for the production of pair $Z$ bosons decaying four massless leptons, $p p \to \ell^+ \ell^- \ell'^+ \ell'^- + X$, at LHC. Spin correlations, interferences and off-shell effects are included throughout. Our result is based on resummed beam-thrust spectrum, which we evaluate next-to-next-to-leading-logarithmic (NNLL$'_{\mathcal{T}_0}$) accuracy first time this process, makes use GENEVA Monte Carlo framework matching PYTHIA8 hadronisation models. compare our predictions with data from ATLAS CMS experiments 13 TeV, finding good agreement.