UCLA

Four-lepton production in proton-proton collisions, pp→(Z/γ∗)(Z/γ∗)→4ℓ$$\mathrm {p}\mathrm {p}\rightarrow (\mathrm{Z}/ \gamma ^*)(\mathrm{Z}/\gamma ^*) \rightarrow 4\ell $$, where ℓ=e$$\ell = \mathrm {e}$$ or μ$$\mu $$, is studied at a center-of-mass energy of 13TeV$$\,\text {TeV}$$ with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 35.9fb-1$$\,\text {fb}^{-1}$$. The ZZ production cross section, σ(pp→ZZ)=17.2±0.5(stat)±0.7(syst)±0.4(theo)±0.4(lumi) pb$$\sigma (\mathrm {p}\mathrm {p}\rightarrow \mathrm{Z}\mathrm{Z}) = 17.2 \pm 0.5\,\text {(stat)} \pm 0.7\,\text {(syst)} \pm 0.4\,\text {(theo)} \pm 0.4\,\text {(lumi)} \text { pb} $$, measured using events with two opposite-sign, same-flavor lepton pairs produced in the mass region 604GeV$$m_{\ell \ell } > 4\,\text {GeV} $$ for all opposite-sign, same-flavor lepton pairs. The results agree with standard model predictions. The invariant mass distribution of the four-lepton system is used to set limits on anomalous ZZZ and ZZγ$$\gamma $$ couplings at 95% confidence level: -0.0012