FIGURE 4.
FIGURE 4.
Mass attenuation coefficient (μ/ρ) of several materials encountered in diagnostic x-ray imaging are illustrated as function of energy. From these plots it can be determined that mass attenuation decreases at a rate of approximately 1/E3 for low energy (∼10 to ∼100 keV) and increases as a function of atomic number (Z) of attenuating material as approximately Z3. With higher Z, presence of “absorption edges” results from increased attenuation of x-rays by photoelectric absorption event at energies equal to binding energies of electrons in the specific element.
