COMMENTS ON THE CLASSICAL APPROACH TO NON-RUTHERFORD CROSS-SECTION CALCULATIONS

Non-Rutherford cross sections are needed in high energy backscattering spectroscopy. Bozoian et al. have developed a classical model and derived an analytical expression to calculate the projectile energy E(nr) at which the scattering cross section begins to deviate from its Rutherford value. We make comments on the model and conclude, through discussions and experiments, that (1) it is useful in estimating the energy value but gives incorrect dependences of E(nr) on the departure factor F and the scattering angle chi, and (2) these inadequacies originate from the classical approach, which is an over-simplified and phenomenal description of nature.