Multiple Scattering of Protons and Nitrogen Ions on Copper

Abstract

Multiple scattering of protons (0.407, 0.851 and 1.45 MeV) and nitrogen ions (1.28 and 2.29 MeV) on copper has been studied. The observed angular distributions are compared with Molière’s theory and some deviations are found. However, these can be diminished by introducing the effective atomic number, z_eff, of incident ions. The appropriate z_eff’s are estimated as 0.87, 0.90 and 0.94 for the protons, respectively. The values 5.2 and 6.2 are obtained for the respective nitrogen ions. The effective atomic number is attributed to the electron screening of slow ion during the collision process.