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On the Momentum Dependence of the Nucleon - Nucleus Optical Potential

M. Kleinmann·R. Fritz·H. Müther·A. Ramos
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Abstract

The momentum dependence of the mean-field contribution to the real part of the optical model potential is investigated employing realistic nucleon-nucleon interactions. Within a non-relativistic approach a momentum dependence originates from the non-locality of the Fock exchange term. Deducing the real part of the optical model from a relativistic Dirac Brueckner Hartree Fock approximation for the self-energy of the nucleons yields an additional momentum dependence originating from the non-relativistic reduction of the self-energy. It is demonstrated that large Fock terms are required in the non-relativistic approach to simulate these relativistic features. A comparison is made between a local density approximation for the optical model and a direct evaluation in finite nuclei.

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M. Kleinmann, R. Fritz, H. Müther, A. Ramos. 1994-02-23. On the Momentum Dependence of the Nucleon - Nucleus Optical Potential. https://doi.org/10.1016/0375-9474(94)90795-1

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