A Geiger-Muller Counter for Measuring the Beta-ray Activity of Liquids, and its Application to Medical Tracer Experiments

Abstract

A G-M counter of the jacketed tube type for β-ray measurements on liquid samples is described, together with a convenient means of mounting in a lead shield. It is shown that the counting rate obtained when the counter is filled is proportional to the concentration of radioactive substance in the solution. Methods for applying corrections for errors due to dead time of the counter and for variations in specific gravity of the solution are given, together with a calibration curve showing the absolute efficiency of the counter for various radioactive isotopes. The counter has proved useful for measurements of the radioactivity of whole blood, plasma, urine, etc., in medical tracer experiments.