Accurate measurements of elastic- and inelastic-scattering differential cross sections are obtained over a wide angular range for 11 MeV neutrons incident on 88Sr, 90Zr and 92Mo. The absolute cross sections are accurate to better than 5%. The parameters of complex optical potentials were extracted from the elastic-scattering data and applied via the collective model to the description of the cross sections of the first 2+ state of each isotope. Deformation parameters βnn′ (and lengths) δ = βR) were obtained for the quadrupole excitations and compared with similar parameters obtained from (p, p′) data on the same nuclei. The results clearly indicate that βnn′ > βpp′ for the N = 50 isotones, in good agreement with the theoretical predictions of Madsen, Brown and Anderson. The values of βnn′ and βpp′ are used to extract the isoscalar and isovector deformation parameters β0 and β1.
- Nuclear reactions
ASJC Scopus subject areas
- Nuclear and High Energy Physics