Standardization of 139Ce by the liquid scintillation counting using the triple to double coincidence ratio method

A good agreement of the results of standardization of 139Ce by the TDCR method using RC and LPRI LS-counters was obtained. The results were confirmed by the 4πβ(LS)–γ coincidence, 4πγ(NaI), 4πβ(PC)–γ coincidence and X and γ spectrometer methods. The detection efficiency determination was improved by calculation of the Compton effect scintillation spectrum including the scattered photons events. A substantial modification of the TDCR method was introduced by a new parameter K3=εT/εD3 being the triple to double in third power counting efficiency ratio.