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arXiv · 1903.04736

Potential model for nuclear astrophysical fusion reactions with a square-well potential

R. Ogura·K. Hagino·C. A. Bertulani
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Abstract

The potential model for nuclear astrophysical reactions requires a considerably shallow nuclear potential when a square-well potential is employed to fit experimental data. We discuss the origin of this apparently different behavior from that obtained with a smooth Woods-Saxon potential, for which a deep potential is often employed. We argue that due to the sharp change of the potential at the boundary the radius parameter tends to be large in the square-well model, which results in a large absorption radius. The wave function then needs to be suppressed in the absorption region, which can eventually be achieved by using a shallow potential. We thus clarify the reason why the square-well potential has been able to reproduce a large amount of fusion data.

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R. Ogura, K. Hagino, C. A. Bertulani. 2019-03-12. Potential model for nuclear astrophysical fusion reactions with a square-well potential. https://doi.org/10.1103/physrevc.99.065808

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