JAERI 1287 JNDC Nuclear Data Library of Fission Products Fir
JAERI 1287 JNDC Nuclear Data Library of Fission Products Fir
JAERI 1287 JNDC Nuclear Data Library of Fission Products Fir
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2 <strong>JNDC</strong> <strong>Nuclear</strong> <strong>Data</strong> <strong>Library</strong> <strong>of</strong> <strong>Fission</strong> <strong>Products</strong> <strong>JAERI</strong> <strong>1287</strong><br />
revision <strong>of</strong> the old library including the fruits <strong>of</strong> his study on estimation method 20 ) <strong>of</strong> the half<br />
lives and the average beta- and gamma-ray energies Ep and Er released per one disintegration<br />
for data-unknown nuclides.<br />
In spite <strong>of</strong> these elaborations, the agreement between calculation and experiment is not<br />
satisfactory for short cooling-time in the range 1 to 1,000 s. Schmittroth & Schenter 21 ' 22 )<br />
pointed out the importance <strong>of</strong> uncertainty <strong>of</strong> the values Ep and Er . Schmittroth estimated<br />
unknown Ep and Er based on measured beta strength functions 23 ^. French and English<br />
files apply a relatively simple method to estimate these values 17 ' 18 ^. One <strong>of</strong> the present<br />
authors developed an estimation method <strong>of</strong> Ep and Er 24 ) on the basis <strong>of</strong> gross theory <strong>of</strong> beta<br />
decay 25 ' 26 ) as a part <strong>of</strong> the activity <strong>of</strong> the Decay Heat Evaluation Working Group (DHEWG)<br />
<strong>of</strong> the Japanese <strong>Nuclear</strong> <strong>Data</strong> Committee (<strong>JNDC</strong>). Recently, DHEWG has completed the<br />
<strong>Fission</strong> Product <strong>Nuclear</strong> <strong>Data</strong> <strong>Library</strong> for summation calculations by compiling recent experimental<br />
results and by estimating unknown decay data <strong>of</strong> short-lived nuclides by the gross<br />
theory <strong>of</strong> beta decay. This library contains the complete set <strong>of</strong> basic data on 1172 fission<br />
product nuclides needed for the summation calculation. Nearly a half <strong>of</strong> them are short-lived<br />
fission products with beta-decay Q-values larger than 4~5 MeV, which play an important<br />
role in the decay power in the short cooling time range.<br />
In Section 2, the nuclear data <strong>of</strong> fission products in the present <strong>JNDC</strong> library are described<br />
with the explanation <strong>of</strong> the data estimation method for nuclides with no experimental<br />
information. The calculated decay power <strong>of</strong> fission products will be compared with measured<br />
results in Section 3. In Section 4, the decay power will be calculated for the burst instantaneous<br />
fission, one year irradiation and the infinite irradiation <strong>of</strong> various fissionable nuclides<br />
and the results will be given in tabular forms and equations. The conclusions will be described<br />
in Section 5.
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