Activity standardization by means of a new TDCR-Cerenkov counting technique.
Samples containing high-energy beta emitters in hydrochloric acid were measured in an in-house built triple-to-double coincidence counter. For the analysis of the results, a new method was developed that is based on a free parameter model. Formulas for the determination of the counting efficiencies were derived assuming a Poisson distribution for the generation of photoelectrons at the photocathodes and applying the Frank and Tamm theory to the production of Cerenkov light. The anisotropy effect for the emission of Cerenkov light was taken into account. The activities determined with the new method were compared with the results from other primary standardization techniques. The following radionuclides were successfully studied: (32)P, (89)Sr, (90)Y, (204)Tl and (106)Rh.
Kossert
K
K
Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany. karsten.kossert@ptb.de