The processes with leptons and jets in the final state were investigated in pp interactions at energies of 7, 8 and 13 TeV. The inclusive differential spectra of the jets were measured at 7 TeV and the angular and energy characteristics of the third jet in multijet events were investigated in comparison with generators at energies of 8 and 13 TeV. For the first time, the process of electroweak Z-boson production accompanied by two jets was observed at pp-interaction energies of 7 and 8 TeV with significance values of 2.6 and 5, respectively, and its cross section was measured. For the first time, an excess of events with a dimuon mass of 28 GeV was observed in the spectrum of dimuon masses produced accompanied by a b-jet in two complementary categories of events at a pp-collision energy of 8 TeV. During the preparation of the CMS experiment, the fundamental possibility of observing resonances of the upsilon and J/psi families under conditions of high detector loading during the PbPb interactions with an energy of 5.5 TeV/n-n was demonstrated. During the research, specific algorithms for calibrating the hadron calorimeter and reconstructing jets were developed.

(Based on the materials of the doctoral thesis.)