| 摘要 |
PROBLEM TO BE SOLVED: To obtain aβ-ray measuring instrument which can be applied to a personal exposure dosemeter and has little energy dependency, by using a pulse-height discriminator circuit which outputs a standardized signal only for a pulse having a peak value within a specific voltage range. SOLUTION: Aβray enters aβ-ray detecting element 2 through an incidence window 4 and generates an electric charge correlating to the energy of theβray and this generated electric charge is converted, into a voltage pulse signal by an amplifier circuit 5 and then inputted to a pulse-height discriminator circuit 8. The pulse-height discriminator circuit 8 outputs a pulse signal standardized to have a fixed waveform peak value, only when the peak value of the inputted voltage pulse signal is within a voltage range set beforehand, and this standardized pulse signal is counted by a counter circuit 9. The sensitivity ofβ-ray measurement is varied according to the range of a specific voltage set for the pulse-height discriminator circuit 8. By regulating the set value of the pulse- height discriminator circuit 8, accordingly, measurement of the dose of theβray depending little on the energy in terms of the sensitivity to theβray can be executed even in a place whereβ-ray emitting nuclides different in the maximumβ-ray energy are present mixedly.
|
