Development of a gamma camera system for high-energy gamma photon for quantitative observation of Cs movement in a plant body

植物体内放射性セシウムのイメージングのための高エネルギー線対応型ガンマカメラの開発

河地 有木; 尹 永根; 鈴井 伸郎; 石井 里美; 吉原 利一*; 渡部 浩司*; 山本 誠一*; 藤巻 秀

Kawachi, Naoki; Yin, Y.-G.; Suzui, Nobuo; Ishii, Satomi; Yoshihara, Toshihiro*; Watabe, Hiroshi*; Yamamoto, Seiichi*; Fujimaki, Shu

We developed an original gamma camera system to image radiocesium in a plant. The gamma camera was designed for high-energy gamma photons from Cs radiocesium (662 keV). We performed tests to evaluate the position resolution and quantitative linearity of the gamma camera. The best spatial resolution of this gamma camera was determined to be 19.1 mm in full width at half maximum at the center of the field-of-view. And a result shows a quantitative linearity of the image data with a correlation of = 0.9985 between the source activity and the count rate. We conclude the gamma camera system has sufficiently high capability to obtain quantitative and dynamic images of Cs movement in intact plants.