Extension of a nuclear reaction calculation code CCONE toward higher incident energies — multiple preequilibrium emission, and spectrum in laboratory system

Abstract

A nuclear reaction calculation code CCONE, which was developed for nuclear data evaluation for JENDL/AC-2008 and JENDL-4, has been upgraded to improve the prediction accuracy for calculated cross sections at nucleon incident energies higher than 20 MeV. Multiple particle emission, in which nucleons and complex particles up to α-particle are involved, from pre-equilibrium reaction process was implemented based on the sequential-decay calculations for all produced exciton states within the framework of the two-component exciton model. The effect of velocity-change of particle-emitting nuclei on the multiple emission in preequilibrium and compound processes, which was not included in the previous evaluations, was taken into account to obtain spectra in the laboratory system using an average velocity approximation for each composite/compound nucleus. Calculated nucleon emission spectra at nucleon incident energies from 20 to 200 MeV were compared with experimental and evaluated data for the proton-and neutroninduced reactions on 27 Al. The present results are in good agreement with experimental data. It was found that their predictions were better than those of JENDL/HE-2007 especially for low emission energies at high incident energies. Keywords: nuclear reaction; cross section; energy spectrum; preequilibrium process; exciton model; multi-particle emission; cluster emission; nuclear data IntroductionThe latest version of Japanese Evaluated Nuclear Data Library, JENDL-4.0 [1], was released in 2010. It included the cross sections for neutron-induced reactions below 20 MeV mainly for nuclear energy applications. At Nuclear Data Center, Japan Atomic Energy Agency(JAEA), it was planned to place emphasis on higher energy data after the release of JENDL-4.0. A special purpose file for high energy nuclear data was re- . The CCONE code uses modern nuclear reaction modelings and parametrizations integrating direct, preequilibrium and compound reactions and also has large

Development of a Reference Database for Beta-Delayed Neutron Emission

“…Odd-mass nuclei were treated in the same way as the even-mass nuclei, and the blocking and polarization effects caused by coupling between valence particle(s) and core nuclei were not considered. The HF statistical model implemented in the code CCONE [204] was used to calculate the competition between DN and γ decays. The global neutron optical potential of Ref.…”

Unified description of the coupled-channels and statistical Hauser-Feshbach nuclear reaction theories for low energy neutron incident reactions

“…J. Raynal's ECIS code has been widely used for this purpose. Exceptions are the CCONE [20,21] and CoH 3 [22,23] codes, those include a private T lj generator internally.…”