Measurements of production cross sections and constraints on anomalous triple gauge couplings at

The production of Z boson pairs in proton-proton ( $$ ) collisions, $$ , where $$ or $$ , is studied at a center-of-mass energy of 13 $$ with the CMS detector at the CERN LHC. The data sample corresponds to an integrated luminosity of 137 $$ , collected during 2016-2018. The $$ production cross section, $$ , measured for events with two pairs of opposite-sign, same-flavor leptons produced in the mass region $$ is consistent with standard model predictions. Differential cross sections are also measured and agree with theoretical predictions. The invariant mass distribution of the four-lepton system is used to set limits on anomalous $$ and $$ couplings.