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arXiv · 1911.10050

An approximation to the Woods-Saxon potential based on a contact interaction

C. Romaniega·M. Gadella·R. M. Id Betan·L. M. Nieto
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Abstract

We study a non-relativistic particle subject to a three-dimensional spherical potential consisting of a finite well and a radial $\delta$-$\delta'$ contact interaction at the well edge. This contact potential is defined by appropriate matching conditions for the radial functions, thereby fixing a self adjoint extension of the non-singular Hamiltonian. Since this model admits exact solutions for the wave function, we are able to characterize and calculate the number of bound states. We also extend some well-known properties of certain spherically symmetric potentials and describe the resonances, defined as unstable quantum states. Based on the Woods-Saxon potential, this configuration is implemented as a first approximation for a mean-field nuclear model. The results derived are tested with experimental and numerical data in the double magic nuclei $^{132}$Sn and $^{208}$Pb with an extra neutron.

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C. Romaniega, M. Gadella, R. M. Id Betan, L. M. Nieto. 2019-11-21. An approximation to the Woods-Saxon potential based on a contact interaction. https://doi.org/10.1140/epjp/s13360-020-00388-7

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