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arXiv · nucl-th/9905045

Phenomenological spin-orbit three-body force

Alejandro Kievsky
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Abstract

In order to improve the description of the N-d vector analyzing powers Ay and iT11 (the so-called Ay puzzle) a spin-orbit three-body force has been introduced. The L.S term in the NN potential has been modified including a two-parameter three-body function depending on the hyperradius ρ. The modification has been performed in channels where the pair nucleons (i,j) are coupled to spin Sij=1 and isospin Tij=1. Calculations have been done in the energy region from Elab=648 keV up to Elab=10 MeV. A noticeable improvement in the description of the polarization observables has been obtained

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Alejandro Kievsky. 1999-05-20. Phenomenological spin-orbit three-body force. https://doi.org/10.1103/physrevc.60.034001

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