Measurement of Reaction Rate Ratio of Capture to Fission and Relative Production Fraction of Excited-to Ground-States of Am241

通过使用京都大学临界装置（KUCA），在具有广泛分布的光谱指数的各种芯中测量Am 241和Np 237的裂变反应和俘获反应，如下所述。(1)KUCA计数装置和中子场的研制（2）精确测量Am 241裂变截面的实验误差<3%（3）精确测量（实验误差<3%）。（4）利用最新的核数据库对这些实验进行精确的分析。发现最新的库仍高估了两种核素的裂变截面约20%，这在先进堆的设计或研究中应加以改进。

Fission reaction and capture reactions of Am241 and Np237 were measured in various cores with widely distributed spectrum indices by using the Kyoto University Critical Assembly (KUCA) as follows. (1) Preparation of a counting equipment and neutron fields in KUCA (2) Accurate measurement (experimental error <3%) of fission cross sections of Am241 (3) Accurate measurement (experimental error <3%) of fission cross section of Np237 (4) Precise analysis of those experiments by using the newest nuclear data libraries.From the present results, it was found that the newest libraries still overestimates the fission cross section of both nuclides about 20% which should be improved for design or research of the advanced reactors.