Theoretical evaluation of neutron-nucleus scattering parameters from experimental data in the 6 <= A < 60 mass region

Systematic calculations of the neutron-nucleus scattering parameters at sev eral neutron energies E-i < 2 keV have been performed for 37 isotopes (Li-6 , ... Co-59) in the mass region of 6 less than or equal to A less than or e qual to 60, using the large compilation of experimental neutron-nucleus sca ttering data obtained in Garching. In the first stage of these calculations , the s-wave potential scattering radius R', the scattering lengths b(coh), b(+/-), and the bound state parameters (E-b, Gamma(gamma r), g Gamma(n)(0) ) have been calculated for each isotope, employing the general least square s fit (GLSQF) for the experimental and the corresponding theoretical values of the total neutron-nucleus cross sections sigma(tot)(exp)(E-i) at severa l energies E-i, absorption cross sections sigma(abs)(E-0) and of the cohere nt scattering lengths b(coh). The theoretical expressions for these paramet ers were deduced on the basis of the usual S-matrix formalism with no assum ption about the particular shape of the optical model potential. In the sec ond stage of our calculations, the spherical Fiedeldey-Frahn optical potent ial was employed for the pure theoretical description or the above mentione d neutron-nucleus scattering characteristics. The results obtained have bee n analyzed and compared with the values deduced from measurements.