On contamination of Bi4Ge3O12 single crystals with 207Bi isotope

Research paper by B. M. Shavinskii, A. A. Galitskii, L. M. Levchenko, V. N. Mit’kin

Indexed on: 14 Jun '16Published on: 14 Jun '16Published in: Radiochemistry


Two versions of generation of 207Bi radionuclide are known from the literature: natural phenomena (cosmic rays) and technogenic factors (high-power nuclear weapons tests). The amounts of the generated radionuclide are so large that it can be detected even in Bi4Ge3O12 (BGO) scintillator. Previously we demonstrated that natural phenomena cannot generate these amounts of 207Bi. The identification of 207Bi of cosmic origin in BGO is doubtful. BGO crystals are inevitably contaminated with isotopes from natural radioactive series, which are significant components of the background radiation of the Earth. Contamination with 227Ас due to several factors is possible. The decay of 211+211m Po to the energy levels of 207m Pb can be misinterpreted as the 207Bi decay.