Neutron Cross-Section Evaluations for 238U up to 150 MeV

Investigations aimed at the development of neutron cross-section evaluations for 238U at intermediate energies are briefly described. The coupled-channels optical model is used to calculate the neutron total, the elastic and reaction cross sections, and the elastic-scattering angular distributions. Evaluations of the neutron and charged particle emission cross sections and of the fission cross sections are obtained on the basis of the statistical description that includes direct, preequilibrium, and equilibrium mechanisms of nuclear reactions. The Kalbach parameterization of angular distributions is used to describe the doubledifferential cross sections of emitted neutrons and charged particles in ENDF/B-VI format.