Performance of a high sensitivity liquid scintillation whole-body counter

Abstract

The design and performance of a high sensitivity liquid scintillation whole-body counter are described. The liquid scintillator used is based upon medicinal paraffin and total internal reflection is used as the method of light collection. The counter is, therefore, cheap and safe from fire hazard. The performance and sensitivity of the counter are shown to be adequate for the accurate determination of body 40K and the potassium content of a normal (70 kg) man can be measured to 2% accuracy of counting statistics in a counting time of 300 seconds. The counter is, therefore, suitable for experiments in which the counting of numerous persons is required. The calibration of the counter is simple and this is one of the main advantages of the design. The performance of the counter is compared with other high sensitivity counters and its possible uses are discussed. For cheapness, chalk is used as the main shielding material.