Resonance Analysis and Evaluation of the Uranium 235 NeutronInduced CrossSections
Abstract
Neutron cross sections of fissile nuclei are of considerable interest for the understanding of parameters such as resonance absorption, resonance escape probability, resonance selfshielding, and the dependence of the reactivity on temperature. In the present study, new techniques for the evaluation of the ^{235}U neutron cross sections are described. The ReichMoore formalism of the Bayesian computer code SAMMY was used to perform consistent Rmatrix multilevel analyses of the selected neutron crosssection data. The Delta_3 statistics of Dyson and Mehta, along with high resolution data and the spinseparated fission crosssection data, have provided the possibility of developing a new methodology for the analysis and evaluation of neutron nucleus crosssections. The result of the analysis consists of a set of resonance parameters which describe the ^{235}U neutron cross sections up to 500 eV. The set of resonance parameters obtained through a Rmatrix analysis are expected to satisfy statistical properties which lead to information on the nuclear structure. The resonance parameters were tested and showed good agreement with the theory. It is expected that the parametrization of the ^{235}U neutron cross sections obtained in this dissertation represents the current state of art in data as well as in theory and, therefore, can be of direct use in reactor calculations.
 Publication:

Ph.D. Thesis
 Pub Date:
 1990
 Bibcode:
 1990PhDT.......112L
 Keywords:

 URANIUM235;
 Chemistry: Nuclear; Physics: Nuclear; Engineering: Nuclear