Theory in Evaluation of Actinide Fission and Capture Cross Sections

Journal Article · Tue May 24 04:00:00 EDT 2005 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.1945221· OSTI ID:20722394

Lynn, J Eric ^[1]

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1. Group T-16, Los Alamos National Laboratory, New Mexico 87545 (United States)

We discuss the possibilities and limitations of the use of theory as a tool in the evaluation of actinide fission and capture cross sections. We consider especially the target 235U as an example. We emphasize the roles of intermediate structure in the fission cross section and of level width fluctuations in both intermediate structure and fine structure, noting that these lead to a breakdown of Hauser-Feshbach theory at sub-barrier and near-barrier energies. At higher energies (where fluctuation-averaged Hauser-Feshbach theory is applicable) semi-quantitative and intuitive representations of transition state spectra and barrier level density functions have to be tested against experimental data wherever these are available. Adjustment of the fission cross section against inelastic scattering to the much better known levels of the residual nucleus should then lead to a fairly sound estimate of the capture cross section. We compare such estimates with evaluated and experimental data for 235U.

• OSTI ID: 20722394
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 769; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
CAPTURE
COMPARATIVE EVALUATIONS
CROSS SECTIONS
ENERGY-LEVEL DENSITY
FINE STRUCTURE
FISSION
FLUCTUATIONS
HAUSER-FESHBACH THEORY
INELASTIC SCATTERING
INTERMEDIATE STRUCTURE
LEVEL WIDTHS
URANIUM 235