The site characterization around the Fukushima Daiichi nuclear power plant (FDNPP) was conducted to measure the dose rate of radioactive cesium using mobile gamma-ray spectrometry through a backpack survey based on a LaBr3(Ce) detector. Four sites were selected in the Fukushima prefecture with diverse dose rate levels in residence and non-residence areas. One reference site in Sendai city was also designated with a low dose rate in comparison with sites in the Fukushima prefecture. The ambient dose rate was distributed from several tens of dose rate to above 1 μGy h due to the radioactive cesium distributed on the ground of the Fukushima prefecture. To assess the dose rates of Cs and Cs using the backpack survey with a short acquisition time, a good correlation was identified between the dose rate of radioactive cesium and the gross count rate in specific regions of interest (ROIs) with gamma rays from radioactive cesium. The dose rates of Cs and Cs accounted for more than 25% of the ambient dose rate during the survey period. The ratio of the Cs dose rate to the Cs dose rate was shown to be about 30% for all survey sites.

中文翻译：

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使用基于LaBr3（Ce）检测器的移动伽玛射线光谱法，对地面放射性铯诱导的剂量率进行光谱估计。

通过基于LaBr3（Ce）检测器的背包测量，使用移动伽玛射线光谱法，对福岛第一核电站（FDNPP）周围的地点进行了表征，以测量放射性铯的剂量率。在福岛县选择了四个地点，在居民区和非居民区的剂量率水平各不相同。与福岛县的地点相比，仙台市的一个参考地点也被指定为低剂量率。由于放射性铯分布在福岛县的地面上，环境剂量率从几十个剂量率分布到1μGyh以上。要使用背包式调查在较短的采集时间内评估Cs和Cs的剂量率，放射性铯的剂量率与特定关注区域（ROI）中的总计数率之间存在良好的相关性，其中放射性铯具有伽玛射线。在调查期间，Cs和Cs的剂量率占环境剂量率的25％以上。在所有调查地点，Cs剂量率与Cs剂量率之比显示为约30％。