Analysis of activated radionuclides for different concretes based on the proton beam source using PHITS code

The study aimed to analyse the correlation in activation between irradiation particles and concrete components. The activation simulation, conducted using the Particle and Heavy Ion Transport code System (PHITS), involved benchmarking proton particles with the same code system to validate the simulation. The calculation of radionuclide activity was performed for four distinct types of concrete, each divided into 10 layers. These concretes featured unique components and compositions, with two containing five impurities. Most of the radionuclides were found to be activated through thermal neutron capture reaction, with outcomes influenced by the cross-section of these reactions and the presence and quantity of concrete components. Furthermore, impurities, despite being trace elements, exhibited a strong contribution to radionuclide activity due to their higher cross-section compared to other nuclides. The results highlight the importance of identifying the specific features of each concrete shield, providing essential insights for preparing against activation during facility decommissioning.