Cancellation of Leading Contributions to Radiative Corrections to the Cross Section for Elastic Electron–Proton Scattering in Experiments Devoted to Measuring the Proton Charge Radius

A cancellation of leading contributions to radiative corrections to the cross section for elastic electron–proton scattering for experiments devoted to measuring the proton charge radius is studied. The cancellations occur in the contribution of electron interaction with the electromagnetic field. It is shown that, under experimental conditions where the recoil proton is detected, there occurs cancellation in the one-loop approximation not only for the terms containing large logarithms but also for the constants at these logarithms and that a nonzero electron contribution to radiative corrections appears starting from terms that are proportional to Q/E, where Q is the momentum transfer and E is the electron energy in the rest frame of the primary proton.