Effective atomic number studies in different soils for total photon interaction in the energy region 10–5000 keV

Abstract

Effective atomic numbers ( Z eff) of 12 different soil samples were computed for total photon interaction cross sections using theoretical data over a wide energy region from 10 to 5000 keV. It is seen that Z eff of a composite material, like soil, changes with a change in energy. With an increase in energy from 10 to 20 keV, Z eff increases, then remains nearly constant up to 40 keV but decreases sharply from 40 to 400 or 500 keV, and a further comparatively small rate of decrease up to 1500 keV. However, there is a small but continuous increase in Z eff with photon energy increases of 1500–5000 keV. This significant change in Z eff of soil is due to variations in the domination of different interaction processes in different energy regions as well as to the large number of elements present in the soil.