Surrogate ratio method in the actinide region using the (α,α'f) reaction

In the Surrogate Method, the measured decay probability of a compound nucleus formed via a direct reaction is used to extract the cross section for a reaction with a different entrance channel that proceeds through the same compound nucleus. An extension of the Surrogate Method, the Surrogate Ratio Method (SRM), uses a ratio of measured decay probabilities to infer an unknown cross section relative to a known one. To test the SRM we compare the direct-reaction-induced fission probability ratio of U234(α,α'f) to U236(α,α'f) with the ratio of cross sections of U233(n,f) to U235(n,f). These ratios were found to be in agreement over an equivalent neutron energy range of 0.4-18 MeV. © 2009 The American Physical Society.