Measurement of the differential ZZ+jets production cross sections in pp collisions at $\sqrt{s} = 13$ TeV

Diboson ZZ production in association with jets in the fully leptonic final states in proton-proton collisions, $\textrm{pp} \to (\textrm{Z}/\gamma^*)(\textrm{Z}/\gamma^*) \to 2\ell2\ell'$, ($\ell,\ell' = \textrm{e}$ or $\mu$), is studied at a center-of-mass energy of 13 TeV. The data sample corresponds to an integrated luminosity of 138 fb$^{-1}$ collected during 2016-2018 with the CMS detector at the LHC. Differential distributions and normalized differential cross sections are measured as a function of the number of jets, as a function of the transverse momentum $p_T$, pseudorapidity $\eta$, invariant mass and $\Delta\eta$ of the highest-\pt and second-highest-\pt jets, and as a function of the invariant mass of the four leptons with different jet multiplicities, and compared to theoretical predictions. The predictions in general agree with the data, but in some regions significant discrepancies between predicted and measured values are observed.