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Effective atomic numbers () of scientific samples (rare earth) were determined experimentally by scattering of 59.54 keV gamma photons from 5 Ci241Am annular radioactive source. The scattered gamma photons were collected by using a high-resolution HPGe semiconductor detector placed at to the incident beam. This experiment was carried out on several elements in the atomic range for 59.54 keV incident photons. Photopeak efficiency and air and sample absorption corrections were performed on Rayleigh to Compton scattering intensity ratio; then the ratio was plotted as a function of atomic number and a fit curve was constituted. The effective atomic numbers of rare earth oxide samples were determined by this fit curve. Also, related parameters were determined by absorption technique with the same incident photon energy. Obtained values from this fit curve were compared to theoretical values and were found to closely agree with theoretical calculations.

Mass attenuation coefficient, μm, atomic cross-section, σi, electronic cross-section, σe, effective atomic number, Zeff and effective electron density, Nel, were determined experimentally and theoretically for some vitamins (retinol, beta-carotene, thiamine, riboflavin, niacinamide, pantothenic acid, pyridoxine, biotin, folic acid, cyanocobalamin, ascorbic acid, cholecalciferol, alpha-tocopherol, ketamine, hesperidin) at 30.82, 59.54, 80.99, 356.61, 661.66 and 1,408.01 keV photon energies using a NaI(Tl) scintillation detector. The theoretical mass attenuation coefficients were estimated using mixture rules. The calculated values were compared with the experimental values for all vitamins.