Technology development to evaluate dose rate distribution and to search for fuel debris submerged in water for decommissioning of Fukushima Daiichi Nuclear Power Station, 2; Construction of radiation sources and three-dimensional plant model for evaluation of dose rate distribution

Okumura, Keisuke; Sato, Wakaei; Maeda, Hirobumi; Wakaida, Ikuo; Washiya, Tadahiro; Katakura, Junichi*

no journal, , 

In order to develop the evaluation technology of the most probable radiation source and dose rate distributions in the primary containment vessel (PCV), we evaluated the radiation source distribution based on the results of fuel burn-up calculation, activation calculation of structural materials and severe accident analysis. Then, we built a three-dimensional PCV model for the particle transport Monte Carlo calculation code PHITS. From the PHITS calculation, we obtained the response function of the dose rate distribution due to each unit radiation source.