大気ガンマ線のダイナミックスペクトル

抄録

This note describes a method of direct measurement of airborne gamma-rays primarily from ²²²Rn daughters using a NaI (Tl) scintillation spectrometer with lead shields. This method has the advantage of being able to maintain the system easily compared to other usual systems including a pump. The pulse-height distributions are successively fed to a floppy disk in a personal computer every unit time. The gain shifts can be corrected automatically by a computer program. This technique would be applicable to the estimation of ²²²Rn daughters concentration and to examination of disequilibrium between ²¹⁴Pb (RaB) and ²¹⁴Bi (RaC) and of those height distribution up to about 200 m. The accuracy for estimating the concentration is as good as that of the filter method.