文章基本信息

标题：Transport Calculation of Neutrons Leaked to the Surroundings of the Facilities by the JCO Criticality Accident in Tokai-mura
其他标题：Transport Calculation of Neutrons Leaked to the Surroundings of the Facilities by the JCO Criticality Accident in Tokai-mura
本地全文：下载
作者：TETSUJI IMANAKA
期刊名称：Journal of Radiation Research
印刷版ISSN：0449-3060
电子版ISSN：1349-9157
出版年度：2001
卷号：42
期号：SUPPL
页码：31-44
DOI：10.1269/jrr.42.S31
摘要：A transport calculation of the neutrons leaked to the environment by the JCO criticality accident was carried out based on three-dimensional geometrical models of the buildings within the JCO territory. Our work started from an initial step to simulate the leakage process of neutrons from the precipitation tank, and proceeded to a step to calculate the neutron propagation throughout the JCO facilities. The total fission number during the accident in the precipitation tank was evaluated to be 2.5×10 18 by comparing the calculated neutron-induced activities per 235 U fission with the measured values in a stainless-steel net sample taken 2 m from the precipitation tank. Shield effects by various structures within the JCO facilities were evaluated by comparing the present results with a previous calculation using two-dimensional models which suppose a point source of the fission spectrum in the air above the ground without any shield structures. The shield effect by the precipitation tank, itself, was obtained to be a factor of 3. The shield factor by the conversion building varied between 1.1 and 2, depending on the direction from the building. The shield effect by the surrounding buildings within the JCO territory was between 1 and 5, also depending on the direction.
关键词：JCO criticality accident; Neutron transport; Neutron induced activity; Monte-Carlo; MORSE