Photonuclear production of medical radioisotopes ¹⁶¹Tb and ¹⁵⁵Tb

The production possibility of ¹⁶¹Tb and ¹⁵⁵Tb by irradiating of natural dysprosium with gamma rays obtained by decelerating an electron beam with an energy of 55 MeV has been demonstrated experimentally. The yield of ¹⁶¹Tb was 14.4 × 10³ Bq × μA^-1 × h^-1 × cm² × g_Dy2O3^-1. Simultaneously, upon irradiation, ¹⁵⁵Dy is formed with the yield of 25 × 10³ Bq × μA^-1 × h^-1 × cm² × g_Dy2O3^-1, which leads to the formation of 1.6 × 10³ Bq × μA^-1 × h^-1 × cm² × g_Dy2O3^-1 of ¹⁵⁵Tb. It has been shown that the isolation of terbium radioisotopes from tens of mg of dysprosium target can be achieved by extraction chromatography, and final separation yield was 39%. The impurity of ¹⁶⁰Tb is 7.3% of the ¹⁶¹Tb activity at EOB.