X-Ray Interaction and the Electronic, Atomic Cross-Sections and Compton Mass-Attenuation Coefficients of Human Blood, Breasts, Eye Lens, Ovaries, and Testis

The Klein–Nishina formula is used to calculate and investigate the electronic cross-section, atomic cross-section, and Compton mass attenuation coefficients for the human blood, breasts, eye lens, ovaries, and testis, using X-rays in the 0.1–20 MeV energy range. The effects of radiation energy, tissue effective charge number, tissue density, and tissue electronic density on these parameters were studied. The results show that the electronic cross-section and atomic cross-section decrease with increasing radiation energy. These parameters are found to be linearly increasing when the density and electron density of a tissue increase. This increase is more rapid with a bigger slope when the electron density increases as compared to the density of each tissue. A complex relationship between these coefficients and the effective charge number Zeff of tissues is observed because Zeff changes with the energy and linear attenuation coefficient of a tissue. The Compton mass attenuation coefficient is found to be dependent on the effective charge number to mass number ratio Zeff/Aeff instead of just the effective charge number. This increase in the Compton mass attenuation coefficient with increasing Zeff/Aeff is rapid for the lower values of Zeff/Aeff. However, for a higher Zeff/Aeff ratio, the increase is very slow and becomes almost constant for X-ray energies above 10 MeV. The calculated parameters are useful in determining radiation dose for the investigated tissues and their response to low and high-energy X-rays. The results and outcomes are also very useful in shielding and protecting tissues from the hazards of radiation. These parameters are also helpful in determining the scattered and optimum doses to improve image quality and treatment options in radiology and radiation therapy to offer the best care.