Affiliation:
1. Belarusian State Institute of Metrology
2. Euphrosyne Polotskaya State University of Polotsk
3. Belarusian State University
Abstract
In this paper, the radiological and economic issues of dismantling cyclotrons of various types, the accumulation
of radionuclides in the details of the cyclotron itself, and the activation of the walls of the cyclotron bunker
due to the capture of secondary neutrons are considered. As a result of (n,γ)-reactions on thermal neutrons, radionuclides
152Eu, 60Co, 46Sc are formed in the concrete of the cyclotron bunker with a half-life of 2,6 to 14 years
and an activity of 0,1–11 kBq/kg. The maximum of their distribution usually lies at a depth of 10–15 cm. In the
details of the cyclotron and the metal infrastructure of the bunker, the main radionuclides are 54Mn, 57Co, 65Zn.
The analysis of the accumulation of long-lived radionuclides is of great importance for the design of new cyclotron
facilities in order to ensure radiation safety and storage of radioactive waste and, as a result, to minimize the
radiation exposure of personnel during the dismantling of the cyclotron.
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