A.V. Belousov - Ph.D. (Phys.-Math.), Associate Professor, Faculty of Physics, Lomonosov Moscow State University, E-mail: belousovav@physics.msu.ru A.A.Belianov - Junior Research Scientist, Faculty of Physics, Lomonosov Moscow State University G.A.Krusanov - Post-graduate Student, Faculty of Physics, Lomonosov Moscow State University. E-mail: krusa-nov@physics.msu.ru A.P. Chernyaev - Dr.Sc. (Phys.-Math.), Professor, Head of Department, Faculty of Physics, Lomonosov Moscow State University

Brachytherapy is a widely used method for treating tumors. When using such approach, a source of radiation is placed in-side or near a tumor. Main advantage of this method is in using small sources of radiation. This allows to deliver dose di-rectly to tumor, diminishing the collateral damage to adjacent tissues. Currently used sources include 60Co, 137Cs, 125I, 192Ir. They have their own advantages and disadvantages. The goal of this paper is to select new brachytherapy sources. To do so, it is necessary to define criteria for preliminary selection by physical properties, to calculate point dose kernels for already selected options to determine required activity. On the first stage radionuclides are selected from the NuDat database. To be chosen, they have to meet following require-ments: half-life has to be between 10 days and 100 years and a contribution of gamma-rays with energy higher than 10 keV to the intensity is higher than 10%. Fission products of chosen radionuclides were also analyzed. Second stage includes simulation of point dose kernels of selected sources using Geant 4 software. The point source is placed in the center of a water phantom that is presented with a sphere with a radius of 50 cm. Absorbed dose is calculated in spherical layers with a 1 mm thickness. Possibility of production of the sources was investigated using TALYS software. Selection process allowed to highlight following radionuclides: 22Na, 46Sc, 54Mn, 56Co, 58Co, 73As, 74As, 75Se, 83Rb, 85Sr, 88Y, 99Rh, 103Ru, 113Sn, 139Ce, 141Ce, 143Pm, 147Eu, 159Dy, 168Tm, 175Hf, 183Re, 185Os, 195Au, 202Tl.

 

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