Measurements of total fast neutron cross sections for aluminum and barium by application of Si(Li)-detectors

Total neutron cross sections of²⁷Al and natural barium have been determined at bombarding energies in the range between 5.5 MeV and 9.6 MeV by transmission measurements. Si(Li)-detectors were used for neutron spectroscopy via charged particle reactions in the active volumes of the detectors. Inscattering corrections have been made by means of a Monte Carlo computer program. In most cases the measured cross sections have root-mean-square uncertainties of 1% to 3%. Cross sections of barium not yet measured have been calculated using optical model potential parameters obtained from an analysis of the experimental results.