Abstract
The analyzing power of the giant resonance region of the nuclear continuum and of low-lying bound states for incident 60-MeV polarized protons has been investigated in the reaction. The measurements are compared with collective-model distorted-wave Born-approximation calculations employing a spin-orbit transition potential of the full-Thomas form and optical-model parameters which give a good description of the analyzing power for proton elastic scattering from at 60 MeV. The predicted analyzing powers for the giant quadrupole () resonance at MeV and for low-lying bound states with are in qualitative agreement with the measurements for . However, a systematic discrepancy is observed for the quadrupole resonance, where the measurements for are considerably more negative than the calculations. A similar but less pronounced effect is observed for the strongly excited and bound states. Improved fits to the analyzing power for the quadrupole resonance are obtained by reducing the spin-orbit diffuseness parameter or by including an attractive imaginary spin-orbit potential. Analysis of the cross section for a weaker resonance at MeV indicates an assignment. The analyzing power for the unstructured nuclear continuum above the giant resonance region is at most angles between 15 and 40°.
NUCLEAR REACTIONS , , MeV, MeV; measured cross section , analyzing power ; discuss excitation of bound states and giant resonances; collective-model distorted-wave analysis. Enriched target.
- Received 7 July 1976
DOI:https://doi.org/10.1103/PhysRevC.14.1392
©1976 American Physical Society