Abstract
The and reactions are investigated in the continuum discretized coupled channel (CDCC) method with a three-body description () of . I first discuss the properties of , and focus on transition probabilities to the continuum. The existence of a resonance at low excitation energies is confirmed, but the associated transition from the ground state does not have an isoscalar character, as suggested in a recent experiment. In a second step, I study the elastic cross section at MeV in the CDCC framework. I obtain a fair agreement with experiment, and show that breakup effects are maximal at large angles. The breakup cross section is shown to be dominated by the dipole state in , but the role of this resonance is minor in elastic scattering. From CDCC equivalent and potentials, I explore the cross section within a standard three-body model. At small angles, the experimental cross section is close to the Rutherford scattering cross section, which is not supported by the CDCC. A five-body calculation is then performed. Including breakup states in and in the deuteron represents a numerical challenge for theory, owing to the large number of channels. Although a full convergence could not be reached, the CDCC model tends to overestimate the data at small angles. I suggest that measurements of the elastic scattering would be helpful to determine more accurate optical potentials. The current disagreement between experiment and theory on scattering also deserves new experiments at other energies.
3 More- Received 16 March 2020
- Accepted 1 June 2020
DOI:https://doi.org/10.1103/PhysRevC.101.064611
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