Unusual back-angle scattering and the significance of coupled channels in the Ni-60 (alpha, alpha-prime) reactin at Ealpha=40 MeV

Dec, 1974
7 pages
Published in:
  • Phys.Rev.C 10 (1974) 2441-2448

Citations per year

19751985199520052013210
Abstract: (APS)
Cross sections were measured for elastic and inelastic scattering of 40.1-MeV α particles from Ni60 over the range θ=153−189°. The 180° cross section for inelastic scattering from the 2+ excited state at 2.16 MeV was found to be more than an order of magnitude larger than that for the first excited 2+ state at 1.33 MeV and nearly an order of magnitude larger than that for the elastic scattering. The phase of the angular distribution for the 2.16-MeV level is opposite to that of the 1.33-MeV level, but is the same as the elastic scattering. The data are compared with predictions of compound nucleus and coupled-channel reaction theory. While the compound nucleus reaction mechanism does not account qualitatively for these data, the coupled-channel approach is much more successful and indicates that the absorption term in the optical model potential is determined in a very sensitive way by the backangle elastic and inelastic scattering. NUCLEAR REACTIONS Ni60(α, α′), E=40.1 MeV; measured absolute σ(θ), θ=153−189°, coupled-channel analysis.