According to the implementing arrangement between the Japan Atomic Energy Agency (JAEA) and the Korea Atomic Energy Research Institute (KAERI) in the field of radiation protection and environmental radiation monitoring, a joint survey program was performed to assess ground deposition of radioactive cesium in areas surrounding the Fukushima Daiichi Nuclear Power Plants. The purpose of this joint survey was to evaluate the field applications of the developed survey systems and methodologies. Understanding the performance of each system within a cesium-deposited contaminated zone is important for ensuring an appropriate response following a nuclear accident. The results of the measured ambient dose rates determined using each survey method were compared. Two kinds of survey system were used in the mobile gamma-ray spectrometry, which were MARK-M1 (Monitoring of Ambient Radiation of KAERI-the 1st Multipurpose system) based on two LaBr3(Ce) detectors of KAERI and KURAMA-II (Kyoto University Radiation Mapping - II) system with one CsI(Tl) detector of JAEA. First, mobile gamma-ray spectrometry using a backpack survey platform was conducted to assess the distribution of dose rates around specific survey sites, which were expected to be slightly contaminated by radioactive cesium in Minamisoma and Tomioka. A carborne survey using two gamma-ray spectrometers loaded inside a vehicle was successfully conducted to compare the measured dose rates in routes from site to site and verify evaluation methods, including attenuation correction.

中文翻译：

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JAEA 和 KAERI 围绕福岛第一核电站进行的联合环境辐射调查：使用背包式和车载调查平台的移动伽马射线光谱测量的性能。

根据日本原子能机构（JAEA）和韩国原子能研究所（KAERI）在辐射防护和环境辐射监测领域的实施安排，开展了一项联合调查计划，以评估该地区放射性铯的地面沉积情况福岛第一核电站周边。此次联合调查的目的是评估所开发的调查系统和方法的现场应用。了解铯沉积污染区内每个系统的性能对于确保核事故后采取适当的响应非常重要。对使用每种调查方法确定的环境剂量率的测量结果进行了比较。移动式伽马能谱测量使用了两种测量系统，即基于KAERI和KURAMA-II（京都大学）两台LaBr3(Ce)探测器的MARK-M1（KAERI环境辐射监测-第一多用途系统）带有一台 JAEA 的 CsI(Tl) 探测器的辐射测绘 - II) 系统。首先，使用背包调查平台进行移动伽马射线能谱测量，以评估特定调查地点周围的剂量率分布，预计南相马市和富冈市的这些地点将受到放射性铯的轻微污染。使用装载在车辆内的两台伽马射线光谱仪成功进行了车载调查，以比较从站点到站点的路线中测量的剂量率，并验证评估方法，包括衰减校正。