携帯用放射能測定器の2, 3の特性について

抄録

The purpose of this paper is to provide a reference information for directivity and other characters of portable survey meters, which are connected with GM-tube, Bi-cathode GM-tube and scintillation detector.
Directivity of these instruments has sharp character for radiations in order of ³²P-βray, radiations of carnotite and ¹³⁷Cs-γAray. These characters depend on absorption of the probe and the envelope. It is the only special case that these are calculated by the cross section of the materials in the detector head. Then the calculated values agree with the observation values.
In this study, it is interesting with relative counting efficiency for various radiation sources. There is no wide difference between counting efficiency by the GM-tube survey meter and by thescintillation for the radioactive minerals which are secondary or thin layer distribution. It is concluded that the above mentioned property due to abundant ratio of β-and γ-rays of the minerals. Therefore, there is a wide difference between counting efficiency and directivity of the survey meters for the above minerals and these for the others, which have different conditions of distribution and degree of equilibrium.