Measurements of p p → Z Z production cross sections and constraints on anomalous triple gauge couplings at s = 13 TeV

Abstract

The production of Z boson pairs in proton-proton ( $pp$ ) collisions, $pp\to (Z/{\gamma }^{\ast })(Z/{\gamma }^{\ast })\to 2\ell 2{\ell }^{\text{'}}$ , where $\ell ,{\ell }^{\text{'}}=e$ or $\mu$ , is studied at a center-of-mass energy of 13 $\text{TeV}$ with the CMS detector at the CERN LHC. The data sample corresponds to an integrated luminosity of 137 ${\text{fb}}^{-1}$ , collected during 2016-2018. The $ZZ$ production cross section, ${\sigma }_{\text{tot}}(pp\to ZZ)=17.4\pm 0.3\text{(stat)}\pm 0.5\text{(syst)}\pm 0.4\text{(theo)}\pm 0.3\text{(lumi) pb}$ , measured for events with two pairs of opposite-sign, same-flavor leptons produced in the mass region $60<m_{{\ell }^{+}{\ell }^{-}}<120\text{GeV}$ is consistent with standard model predictions. Differential cross sections are also measured and agree with theoretical predictions. The invariant mass distribution of the four-lepton system is used to set limits on anomalous $ZZZ$ and $ZZ\gamma$ couplings.