Fission Product Yield Data for the Transmutation of Minor Actinide ...
Fission Product Yield Data for the Transmutation of Minor Actinide ...
Fission Product Yield Data for the Transmutation of Minor Actinide ...
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cross-section data has been achieved <strong>for</strong> three<br />
different nuclei, 235,238 U and 237 Np.<br />
(b) Reasonable values have been derived <strong>for</strong> <strong>the</strong><br />
outer barrier heights and <strong>the</strong> corresponding<br />
curvatures <strong>of</strong> each mode.<br />
(c) Symmetric and asymmetric fission can be<br />
explained by penetration through different<br />
outer barriers. At sub-barrier neutron incident<br />
energies, <strong>the</strong> least asymmetric mode S1 is<br />
dominant, while above <strong>the</strong> fission threshold<br />
<strong>the</strong> most asymmetric mode S2 becomes<br />
dominant in fission. This behaviour has consequences<br />
<strong>for</strong> <strong>the</strong> observed fission fragment<br />
properties, e.g. fragment mass distribution.<br />
(d) Within <strong>the</strong> concept <strong>of</strong> multi-modal fission, <strong>the</strong><br />
calculations <strong>of</strong> fission fragment mass distributions,<br />
<strong>the</strong> prompt fission neutron multiplicity<br />
and neutron energy spectrum <strong>for</strong> each mode<br />
are feasible from <strong>the</strong> measured fission crosssections<br />
only.<br />
116<br />
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