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Abstract Production cross sections of the Higgs boson are measured in the $${\mathrm{H}} \rightarrow {\mathrm{Z}} {\mathrm{Z}} \rightarrow 4\ell $$ H → Z Z → 4 ℓ ( $$\ell ={\mathrm{e}},{{{\upmu }}_{\mathrm{}}^{\mathrm{}}} $$ ℓ = e , μ ) decay channel. A data sample of proton–proton collisions at a center-of-mass energy of 13 $$\,\text {Te}\text {V}$$ Te , collected by the CMS detector at the LHC and corresponding to an integrated luminosity of 137 $$\,\text {fb}^{-1}$$ fb - 1 is used. The signal strength modifier $$\mu $$ μ , defined as the ratio of the Higgs boson production rate in the $$4\ell $$ 4 ℓ channel to the standard model (SM) expectation, is measured to be $$\mu =0.94 \pm 0.07 \,\text {(stat)} ^{+0.09}_{-0.08} \,\text {(syst)} $$ μ = 0.94 ± 0.07 (stat) - 0.08 + 0.09 (syst) at a fixed value of $$m_{{\mathrm{H}}} = 125.38\,\text {Ge}\text {V} $$ m H = 125.38 Ge . The signal strength modifiers for the individual Higgs boson production modes are also reported. The inclusive fiducial cross section for the $${\mathrm{H}} \rightarrow 4\ell $$ H → 4 ℓ process is measured to be $$2.84^{+0.23}_{-0.22} \,\text {(stat)} ^{+0.26}_{-0.21} \,\text {(syst)} \,\text {fb} $$ 2 . 84 - 0.22 + 0.23 (stat) - 0.21 + 0.26 (syst) fb , which is compatible with the SM prediction of $$2.84 \pm 0.15 \,\text {fb} $$ 2.84 ± 0.15 fb for the same fiducial region. Differential cross sections as a function of the transverse momentum and rapidity of the Higgs boson, the number of associated jets, and the transverse momentum of the leading associated jet are measured. A new set of cross section measurements in mutually exclusive categories targeted to identify production mechanisms and kinematical features of the events is presented. The results are in agreement with the SM predictions. 

A bstract Events containing one or more top quarks produced with additional prompt leptons are used to search for new physics within the framework of an effective field theory (EFT). The data correspond to an integrated luminosity of 41.5 fb − 1 of proton-proton collisions at a center-of-mass energy of 13 TeV at the LHC, collected by the CMS experiment in 2017. The selected events are required to have either two leptons with the same charge or more than two leptons; jets, including identified bottom quark jets, are also required, and the selected events are divided into categories based on the multiplicities of these objects. Sixteen dimension-six operators that can affect processes involving top quarks produced with additional charged leptons are considered in this analysis. Constructed to target EFT effects directly, the analysis applies a novel approach in which the observed yields are parameterized in terms of the Wilson coefficients (WCs) of the EFT operators. A simultaneous fit of the 16 WCs to the data is performed and two standard deviation confidence intervals for the WCs are extracted; the standard model expectations for the WC values are within these intervals for all of the WCs probed.