Beta-Gated Gamma Coincidence Counting with a Phoswich Detector

A special type of phoswich detector system has been evaluated for measurement of radionuclides which decay with emission of time coincident beta and gamma radiation. Background reductions of more than two orders of magnitude have been obtained for the energy region from 500-950 keV. Both NE 102 plastic scintillators and anthracene were evaluated. Advantages and disadvantages of the method are discussed.