Kanji Tasaka, Junichi Katakura

Japan Atomic Energy Research Institute
Tokai-mura, Naka-gun, Ibaraki-ken, 319-11 Japan

Tadashi Yoshida

Nippon Atomic Industry Group Co., Ltd.
4-1 Ukishima-cho, Kawasaki-ku, Kawasaki-shi, 210 Japan

Calculations of decay heat of fission products were reviewed and compared with recent measurements. The calculated decay heat with known nuclear data alone was considerably smaller than the measured result at short cooling times less than 103 s. The estimated decay energies have most significant influences on the decay heat. The theoretical estimation of unknown or imprecisely-known decay energies by the gross theory of beta decay made it possible to reproduce quite well (within ±5%) the decay heat measurements at University of Tokyo (UT) and at Oak Ridge National Laboratory (ORNL) for variety of fissiles. The theoretical estimation of unknown beta decay data by microscopic nuclear structure calculations could also improve the accuracy considerably.

KEYWORDS: decay heat, gamma spectrum, fission product, summation calculation, capture effect, uncertaintly, review