The Determination of Ratios of Effective Cross Sections from Measured Burnup Data for Yankee Rowe

A technique for obtaining cross-section information from experimental isotopic concentration data has been applied to the data from Yankee Core I. The technique involves making a least-squares fit of appropriate transmutation equations to the data. The analysis covers two transmutation chains. One is the plutonium chain which begins with ²³⁸U and ends with americium and curium. The other is a rarer isotope chain which begins with ²³⁵U or ²³⁸U and ends with neptunium and plutonium. Values were obtained for 12 ratios determined by the leastsquares analysis (e.g., ²⁵ = 0.2569 ± 0.0023 and ⁴⁹ = 0.622 ± 0.082). In order to obtain information about the less abundant transuranium isotopes, 15 Yankee Core I samples were analyzed for their isotopic content. The ratios of effective cross sections were also deduced from the data.