Correlation of Radiation Types with Radiation Effects

The effects produced by different types of nuclear radiation can be compared by making use of the available information on radiation-effects mechanisms. One can separate radiation-effects manifestations into three categories: transient radiation effects, which are due to excited and ionized electrons; displacement radiation effects, which are manifestations of atoms displaced from their normal lattice sites in crystalline solids; and chemical radiation effects, which are due to molecular rearrangements occurring as a second stage to ionizing interactions. The effects produced by different primary radiations can be compared by first identifying the manifestation as belonging to one of these three types. For displacement effects one should then compute the relative cross sections for producing displaced atoms and the average size of the displacement cascade produced by the primary recoil atom. Similarly, for transient and chemical effects one should compute the ionization density produced by the incident radiation. Examples of the pertinent cross sections have been calculated for electrons, gamma rays, protons, and neutrons of various energies.