This work is licensed under Creative Commons Attribution–NonCommercial International License
(CC BY-NC 4.0).
The use of the method developed in the CLAS collaboration (JeffersonLab, USA) of improving leptons momentum for more correct studies of finalstate selection of quasi-real photoproduction resulting from the reaction to nearthreshold photoproduction of theJ/ψmeson is described. The radiation photonsthat were detected in electromagnetic calorimeter were studied with electronsand positrons accompanied them in very narrow angles. The method of radiatedphoton selection ofe+e−p′(e′)reaction is given, wheree+e−lepton pair isformed during the decay ofJ/ψmeson.