Article ID Journal Published Year Pages File Type
1834477 Nuclear Data Sheets 2014 5 Pages PDF
Abstract

This paper discusses two common approximations used to calculate average fission cross sections over the compound energy range: the disregard of the WII factor and the Porter-Thomas hypothesis made on the double barrier fission width distribution. By reference to a Monte Carlo-type calculation of formal R-matrix fission widths, this work estimates an overall error ranging from 12% to 20% on the fission cross section in the case of the 239Pu fissile isotope in the energy domain from 1 to 100 keV with very significant impact on the competing capture cross section. This work is part of a recent and very comprehensive formal R-matrix study over the Pu isotope series and is able to give some hints for significant accuracy improvements in the treatment of the fission channel.

Related Topics
Physical Sciences and Engineering Physics and Astronomy Nuclear and High Energy Physics