Color quench correction for low level Cherenkov counting

The Cherenkov counting efficiency varies strongly with color quenching, thus correction curves must be used to obtain correct results. The external 152Eu source of a Quantulus 1220TM liquid scintillation counting (LSC) system was used to obtain a quench indicative parameter based on spectra area ratio. A color quench correction curve for aqueous samples containing 90Sr/90Y was prepared. The main advantage of this method over the common spectra indicators is its usefulness also for low level Cherenkov counting.