MEASUREMENT OF Ni63 WITH A 2π PROPORTIONAL COUNTER

Abstract
Measurement of Ni63, a βemitter with very low maximum energy, is described. External absorption curves were determined in aluminum and a range 8.5 ± 0.5 mg/cm2 was found. This corresponds to a maximum energy of the β radiation of 72.7 ± 2.5 kev, in reasonably good agreement with values obtained by other methods. Self-absorption curves of electrolytically deposited samples were obtained and attempts made to compare these with the theoretical predictions of Gora and Hickey.