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Assessment of dosimetric characteristics of neutron radiation generated by medical linear accelerator of electrons

UDC 615.849.1:614.876
Authors Verenich Kirill Aleksandrovich
Kuten' Semen Adamovich, PhD in Physico-Mathematical Sciences, Researcher
Khrushchinskiy Arkadiy Arkad'evich, PhD in Physico-Mathematical Sciences
Makarevich Kristina Olegovna
Minenko Viktor Fedorovich, PhD in Biological Sciences, Associate Professor
Abstract Purpose. The paper is aimed to study the neutron radiation from medical linear accelerators of high-energy electrons.
Methods. Mathematical modelling of coupled electron-photon and coupled photon-neutron transport was carried out. The calculations were performed using Monte-Carlo simulation.
Findings. Spectra of neutrons in the bunker were calculated. The average energy of neutrons from the head of linear accelerator varies depending on the measurement point. The approximate energy of source neutrons is 0,5 MeV. Scattering from the walls adds a significant part of thermal neutrons to the spectrum. The average energy of neutrons in the maze and outside the procedure room of the bunker is 0,025 eV.
Application field of research. The obtained results of this study could be used in the design of shielding of medical linear accelerators of electrons with energies above 10 MeV.
Conclusions. Although the standard shielding from X-ray radiation from medical linear accelerators is effective for neutron radiation, high-energy electrons produce neutrons that require better shielding to protect doctors and members of public.
Keywords medical electron linac, Monte-Carlo modelling, bremsstrahlung radiation, neutrons, radiation dose, beam therapy, MCNP
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