JAERI 1287 JNDC Nuclear Data Library of Fission Products Fir

JAERI 1287
JNDC Nuclear Data Library of Fission Products
Kanji Tasaka, Hitoshi Ihara, Masatsugu Akiyama'
Tadashi Yoshida *, Zyun-itiro Matumoto and Ryuzo Nakasima
Japanese Nuclear Data Committee
Tokai Research Establishment
Japan Atomic Energy Research Institute
Tokai-mura, Naka-gun, Ibaraki-ken
Received June 3, 1983
Abstract
The JNDC (Japanese Nuclear Data Committee) FP (Fission Product) nuclear data library
for 1172 fission products is described in this report. The gross theory of beta decay has been
used extensively for estimating unknown decay data and also some of known decay data with
poor accuracy. The calculated decay powers of fission products using the present library show
excellent agreement with the latest measurements at ORNL (Oak Ridge National Laboratory),
LANL (Los Alamos National Laboratory) and UTT (University of Tokyo, Tokai) for cooling
times shorter than 10 3 s after irradiation. The calculated decay powers by the existing libraries
showed systematic deviations at short cooling times; the calculated beta and gamma decay
powers after burst fission were smaller than the experimental results for cooling times shorter
than 10 s, and in the cooling time range 10 to 10 3 s the beta-decay power was larger than the
measured values and the gamma decay power smaller than the measured results. The present
JNDC FP nuclear data library resolved these discrepancies in the short cooling time ranges.
The decay power of fission products has been calculated for ten fission types and the results
have been fitted by an analytical function with 31 exponentials. This permits the easy application
of the present results of decay power calculations to a LOCA (Loss-of-Coolant Accident)
analysis of a light water reactor and so on.
Keywords: Fission Product, Decay Data, Fission Yield Data, Neutron Capture Cross Section
Data, Gross Theory, Data Library, Fission Energy, Decay Heat, Evaluation,
Fitting Equation
The work was performed in the evaluation work of the Working Group on Evaluation of Decay Heat,
Japanese Nuclear Data Committee.
* Nuclear Engineering Research Laboratory, Faculty of Engineering, University of Tokyo
** NAIG Nuclear Research Laboratory, Nippon Atomic Industry Group Co., Ltd.
*** Department of Physics, Hosei University