Methodological Research to Improve the Extraction of Near-Threshold Quasi-Real Photoproduction of J/Ψ-Meson Process on Nucleons from Experimental Data of Electroproduction on Hydrogen Nuclei, Obtained by CLAS12 Setup

This work describes the methodological part of the analysis on the study of the near-threshold quasi-real photoproduction of vector mesons on nucleons. The analysis uses experimental data obtained at the CLAS12 (Cebaf Large Acceptance Spectrometer) of the CEBAF (Current Beam Accelerator Facility) of the Jefferson Laboratory (USA). The experimental data on the scattering of 10.6 GeV electrons by a liquid hydrogen target is investigated. The work describes methods for the selection and identification of the final states of completely exclusive near-threshold reactions of (E_γ ≥ 8.2 GeV) quasi-real (Q² ≈ 0) photoproduction of J/ѱ mesons. A step-by-step description of the mechanism for identifying the selection of the final state of a lepton pair and the recoil nucleon is presented. It is shown how the parameters of the distributions of kinematic quantities characteristic of the reactions under study change in the course of the analysis.