03.04.2013 Views

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 ...

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

epresenting model values and thus support model<br />

treatments <strong>of</strong> s Z(A¢) and DZ(A¢) near symmetry.<br />

4.2.4. Models <strong>for</strong> neutron emission<br />

The average total number (NT) <strong>of</strong> nucleons<br />

emitted be<strong>for</strong>e and after scission and <strong>the</strong> average<br />

number <strong>of</strong> neutrons (n A(A)) emitted promptly after<br />

scission to <strong>for</strong>m products with mass number A are<br />

used in model calculations <strong>of</strong> mass and nuclear<br />

charge distributions, respectively, as described in<br />

<strong>the</strong> preceding two sections. NT is used to determine<br />

<strong>the</strong> central mass number (A c = (PA – NT)/2) in<br />

multi-Gaussian mass yield calculations. The<br />

quantity n A(A) is used to approximate complementarity<br />

in A <strong>of</strong> light and heavy fission products, A¢ L +<br />

A¢ H = A F , A¢ = A + n A (A), n A (A) = n T (A)R(A),<br />

where n T(A) is <strong>the</strong> average number <strong>of</strong> neutrons<br />

emitted to <strong>for</strong>m products with mass number A and<br />

<strong>the</strong>ir complements, and R(A) is <strong>the</strong> fraction <strong>of</strong> <strong>the</strong>se<br />

neutrons that <strong>for</strong>m products with A [4.2.4, 4.2.29].<br />

The earlier models required a file <strong>of</strong> n A (A)<br />

values <strong>for</strong> each fission reaction [4.2.3, 4.2.4, 4.2.27,<br />

4.2.29]. Below, a model is proposed that allows<br />

calculation <strong>of</strong> n A (A), and <strong>the</strong>re<strong>for</strong>e FI, etc., <strong>for</strong> any<br />

fission reaction in <strong>the</strong> mass, charge and energy<br />

regions investigated.<br />

4.2.4.1. Low energy systematics<br />

There are no or very few pre-fission neutrons<br />

<strong>for</strong> PE approximately

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!