Abstract
This paper describes a method of measurement of after-pulses of G-M counter using the RI chopper and the result of measurement with it.
G-M counter is alternatively irradiated β-rays by the RI chopper. Output pulses of G-M counter, whose pulses have to be counted during the time of no radiation of β-rays, are supplied to synchronize with RI chopper for coincident gate circuit. Accordingly, only the after-pulses are counted.
The result of after-pulses measurement using the arrangement is not different from the experimental results, which has been already reported, with the pulse modulated irradiation. Namely it is that the rate of generation of after-pulse increases together with the intensity of radiation and an anode voltage of the G-M counter. It is possible, therefore, to measure the characteristics of the after-pulse even if such a simple device as the RI chopper is used.
