  Incident neutron energy dependence of delayed neutron yields of uranium and
plutonium isotopes is investigated. A summation calculation of decay and
fission yield data is employed, and the energy dependence of the latter part is
considered in a phenomenological way. Our calculation systematically reproduces
the energy dependence of delayed neutron yields by introducing an energy
dependence of the most probable charge and the odd-even effect. The calculated
fission yields are assessed by comparison with JENDL/FPY-2011, delayed neutron
activities, and decay heats. Although the fission yields in this work are
optimized to delayed neutron yields, the calculated decay heats are in good
agreement with the experimental data. Comparison of the fission yields
calculated in this work and JENDL/FPY-2011 gave an important insight for the
evaluation of the next JENDL nuclear data.
