Abstract. Structural properties, such as mechanical and electrical properties of materials irradiated with γ -rays are affected by displacement damage. Successive processes with different behaviors ultimately lead to the formation of sets of ‘defects’ within the material, and as an example, it may cause the substance to become brittle. In this study, Monte Carlo codes provide information using a code-based simulation method on primary knock-on atoms, or PKAs, that cause damage. Also, the rate of damage caused by the gamma radiation from the cobalt-60 source on the structural properties of iron is calculated. To access PKA information, a program called GAMMATRACK has been developed. This software provides information about the rejected atoms’ properties and the interaction kinematics. The theoretical calculation method has also been used to confirm the results of the Monte Carlo method. Using the generated secondary electrons, the stopping and range of ions in matter (SRIM) code can calculate the damage caused by gamma radiation. PKA data were extracted by the GAMMATRACK program, which can be used as input for the SRIM code for the systematic analysis of gamma damage. The obtained PKA spectrum for iron agrees with the previous works. It is realised that only monovacancies are produced, and under cobalt-60 irradiation, the possibility of the atom–atom collision is negligible. Therefore, creating PKA cascades will be ruled out. Also, the damage rate for an iron target is calculated at ~10−7, 10−8 (displacement per atom (DPA)/year) for both theoretical and Monte Carlo method (MCNPX + SRIM code) computations.
