[2H11-15] Non-destructive Inspection

[2H13] Development of in-pipe exploration technology in high background radiation environment

(3) Development of a detection technique for low-energy gamma rays

*Yuki Morishita¹, Yukihisa Sanada¹, Miyuki Sasaki¹, Tatsuo Torii^2,3 (1. JAEA, 2. University of Fukui, 3. Fukushima University)

Keywords:decommissioning,, radiation imaging, in-pipe exploration, phoswich detector

We have developed a detector to detect low-energy gamma rays emitted from U and Pu (59.5 keV gamma rays emitted from 241Am) in a background radiation such as Cs-137 gamma rays. The detector consisted of a YAP:Ce scintillator in the first layer, an acrylic light guide in the second layer, and a BGO scintillator in the third layer, with the bottom of the BGO scintillator optically coupled to a 2-inch photomultiplier tube. The output voltage waveforms were collected by a digitizer. By analyzing the difference in signal waveforms, it is possible to develop a detector with sensitivity to only low-energy gamma rays.