Abstract
Angular distributions have been measured for the de-excitation gamma rays from the isoscalar and isovector states populated in the (,) reaction at MeV. Fluctuations in the coefficients, which measure the total excitation cross sections, are observed to decrease with energy toward the high end of the region investigated. The coefficients are still fluctuating at 27 MeV, but exhibit reasonably well-defined average values of about -0.40 and 0.15 for the and levels, respectively. Microscopic distorted-wave calculations based on a realistic matrix interaction, while not sufficient to completely describe the present data, suggest that the isospin dependence of the coefficients is associated with the tensor force. The theoretical calculations have been extended to 50 MeV and this effect of the tensor force persists.
NUCLEAR REACTIONS (,) MeV; measured gamma-ray angular distribution; states miscroscopic DWBA analysis.
- Received 26 October 1979
DOI:https://doi.org/10.1103/PhysRevC.21.1158
©1980 American Physical Society