Scattering process approach to neutron spectrum in fast reactor

The neutron spectrum in a fast reactor is formulated from a new approach for an infinite homogeneous medium and is given in a form that allows explicit evaluation of each scattering collision process. Mathematically, the procedure is equivalent to that based on the balance equation. Numerical evaluation indicates that there exists only small probability of a neutron undergoing inelastic scattering more than several times. Applying the formulas thus derived, an approximate representation of the spectrum has been obtained in a simple form, and which includes the multiple inelastic scattering effects. (author)