ABSTRACT
When x and gamma rays, in the energy range from 0.1 keV to 1 MeV, traverse matter they are attenuated primarily by photoelectric absorption, incoherent scattering, and coherent scattering. The probabilities of these interactions occurring per unit depth of penetration are called cross sections, and the total attenuation cross section μ is related to those for the mechanisms above by () μ = τ + σ I + σ C https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9780203742433/53e9912e-dfc3-42b1-91b1-4eaf447a0f76/content/eq1.tif"/>
