Abstract
Background: Nuclear reactions involving particles play an important role in various astrophysical processes such as the process of heavy element nucleosynthesis. The poorly known low-energy -nucleus optical potential is a key parameter to estimate the rates of these reactions.
Purpose: The -nucleus optical potential can be tested by measuring the cross section of scattering as well as -induced reactions. Low energy elastic scattering on has recently been measured with high precision. The aim of the present work was to complement that work by measuring the cross sections on at low energies. The experimental data shall be used to constrain the -nucleus optical model potential. From this potential the reaction rate can be derived with reduced uncertainties.
Method: The reaction was studied by bombarding Sm targets with beams provided by the cyclotron accelerator of Atomki. The cross section was determined using the activation method. The radiation following the decay of the reaction product was measured with a high-purity germanium (HPGe) detector. The experimental data are analyzed within the statistical model.
Results: The cross section was measured in the -energy range between 13 and 20 MeV in 1 MeV steps, i.e., from close above the threshold. The results were compared with statistical model calculations using various approaches and parametrizations for the -nucleus optical potential, and excellent agreement was obtained for two recent potentials. However, these potentials cannot reproduce literature data for the reaction with the same accuracy.
Conclusions: Constraints for the -nucleus potential were derived from an analysis of the new data and literature data for . These constraints enable a determination of the reaction rate of the reaction with significantly reduced uncertainties of less than a factor of 2.
- Received 8 December 2022
- Accepted 27 January 2023
DOI:https://doi.org/10.1103/PhysRevC.107.025803
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