γ-RAY DETECTION DEVICE

To provide a γ-ray detection device capable of easily detecting significant reduction of a detection efficiency of a γ-ray detection part.SOLUTION: There is provided a γ-ray detection device 10 for γ-ray spectrometry for performing radioactivity quantitative evaluation by a comparative measurement method, in the detection device, a radioactivity quantitative evaluation part 14 executes radioactivity quantitative evaluation by a sum peak method with the radioactivity quantitative evaluation by the comparative measurement method, when a γ-ray spectrum detected by a γ-ray detection part 11 indicates a γ-ray spectrum formed of only a single cascade nuclear species, and if a significant difference is confirmed between the radioactivity quantitative evaluation result by the comparative measurement result and the radioactivity quantitative evaluation result by the sum peak method, it is determined that, the detection efficiency of the γ-ray detection part 11 is deteriorated significantly.SELECTED DRAWING: Figure 1 【課題】γ線検出部の検出効率の劇的な低下を簡易的に検知することができるγ線検出装置を提供する。【解決手段】比較測定法による放射能定量評価を行うためのγ線スペクトロメトリ用のγ線検出装置１０であって、放射能定量評価部１４が、γ線検出部１１によって検出されたγ線スペクトルが単一のカスケード核種のみのγ線スペクトルを示すと、比較測定法による放射能定量評価と共にサムピーク法による放射能定量評価を実施し、比較測定法による放射能定量評価結果とサムピーク法による放射能定量評価結果との間に有意な差が確認されると、γ線検出部１１の検出効率が劇的に低下したおそれがあると判定する。【選択図】図１