Long-Term Continuous In-Situ Measurement of Gamma Rays Using Ge Semiconductor Detector

Abstract

We developed a long-term continuous measurement method for in-situ gamma-ray measurement using a Ge semiconductor detector (in-situ Ge measurement), and performed continuous measurement for 36 months by the method. A measurement system was successfully stably operated for a long period, and it was confirmed that artificial radioactive nuclides were able to be detected at high sensitivity. A counting rate of each of ²¹⁴Pb and ²¹⁴Bi was increased about twice in correspondence to slight increase in environmental radiation dose rate of about 10% as a measurement value of a monitoring post using a NaI (Tl) detector. The problem of discriminating between natural radiation and radiation from man-made source was solved by this system.