Dosimetry of Neutron Flow and Gamma-Radiation for two Neutron Beam Shaping Assembly at the VITA Facility using a Scintillator Detector

The BNCT method is considered one of the promising methods of external beam therapy in the treatment of radioresistant tumors such as glioblastoma, melanoma and others, which selectively destroy cancer cells due to previous accumulations of boron-10 isotopes stable inside them, and subsequent irradiation with epithermal neutrons. As a result of neutron capture by boron, nuclear radiation interacts with the release of a large amount of energy (charged particles with a high linear energy transfer), which leads to the destruction of the cancer cell. This method is distinguished by a short number of treatment sessions compared to traditional radiation therapy (photons and electrons). In this study, the boron dose rate and the dose rate of gamma radiation in air and in a water phantom are measured using a small-sized neutron detector with a pair of cast polystyrene scintillators, one of which is enriched with boron, developed at BINP. Two neutron beam shaping assembly were used, one with a magnesium fluoride crystal moderator and the other with a Plexiglas moderator. The article will present the experimental results, discuss the features of the neutron beam shaping assembly and formulate recommendations for conducting clinical trials of the BNCT technique

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