A method for determining bulk or surface activity concentration of -emitters in
infinitely
thick or thin samples using energy selective detectors without any prior chemical separation or qualitative analysis was introduced in Part I. In addition to that method, a correction procedure is often required in order to compensate for the
-sensitivity of the
-detector. A system or two — preferably identical —detectors positioned to the front and rear side of a sample has been established. The rear side detector is shielded against
-radiation. The
-response of both detectors is determined as a function of
-energy using monoenergetic calibration standards. Response pulses are selected to form 8 or 16 energy intervals, and separate series of correction coefficients are then computed for each interval and standard energy using the ratio of the respective counts. When a sample having mixed
- and
-radiation is evaluated, an
effective
-energy is first calculated from the pulse height distribution of the rear side detector, the appropriate series of correction coefficients is selected and finally net
-counts are generated from the counts of the front side detector. Sensitivities in natural and elevated
-background are presented.