JAEA-Conf 2011-002 - 日本原子力研究開発機構

JAEA-Conf 2011-002
4. Discussion
Figure 8 shows the -ray spectrum calculated from the -feedings obtained by the
TAGS measurement and a continuous -ray cascade model mentioned in the preceeding
chapter. The -feedings go into the energy bins with fixed-width and, then, the-ray
spectrum based on the TAGS results do not show any suructure and the resultant -ray
spectrum becomes a single peaked broad distribution as seen here.
Figure 9 shows the calculated -ray spectrum originating from the -feeding to the
highest energy region where no measurement except for the TAGS gives the feeding, namely,
above 4300keV (see Fig3). This calculation is not enough to make a complete -ray energy
spectra to be included in JENDL. So existing discrete-line data from ENSDF are also taken
into account for the -rays originated from the levels below 4300keV. In this sense we
combined existing data and the latest TAGS data to obtain a complete -ray spectrum.
Figure 1014 shows the -ray spectrum constructed by combining of the current high
resolution data and the TAGS-based calculation as was described above. These results
clearly shows us that the part of the spectrum calculated theoretically with the -feedings
obtained by TAGS measurement are not discrete. On the other hand, the part of the spectra
taken from the current decay schemes has discrete structure. In order to take the balance of
both components above into consideration, we need renormalization. This was done in a
way to reserve both the E and the E values determined by the TAGS measurement.
5Conclusions
The present work is to introduce TAGS data into JENDL. For this purpose, we have to
convert the -feedings obtained by TAGS into the energy spectrum of both the -particles
and -rays in the ENDF/B format. Only the -ray spectrum is dealt with here for Nb-101,
Tc-104,105,106 and Mo-105. The calculation of -ray spectra for Tc-102 and -107 is now
underway. Furthermore, the calculation of -ray spectra from the TAGS -feeding is to be
carried out. We tried to combine the current high resolution data with the latest TAGS data
as far as the -ray spectrum is concerned. By doing this, we aim at advancement in
performance of the summation calculation of decay heat by the JENDL decay data file.
References
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