The Optical Model and Proton Total Reaction Cross Sections

The relation between the calculated total reaction cross section and the optical model parameters is investigated for 17 Mev protons on copper. For both the real and imaginary central potential a Saxon-Woods form factor is used with a Thomas-type spin-orbit potential. A semi-automatic search procedure to find the parameters corresponding to the optimum fit to the elastic scattering is developed. A method is described for the derivation of the optimum adjustments of some or all of the parameters to produce a required change in the predicted reaction cross section with minimum departure from the optimum fit to the elastic scattering results. A 3% change in the reaction cross section can be accommodated for the reaction studied. The scattering of 17 Mev protons by carbon is also briefly considered.