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arXiv · 1708.00878

Coarse graining the Bethe-Goldstone equation: nucleon-nucleon high momentum components

I. Ruiz Simo·R. Navarro Perez·J. E. Amaro·E. Ruiz Arriola
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Abstract

The delta-shell representation of the nuclear force allows a simplified treatment of nuclear correlations. We show how this applies to the Bethe-Goldstone equation as an integral equation in coordinate space with a few mesh points, which is solved by inversion of a 5-dimensional square matrix in the single channel cases and a $10\times10$ matrix for the tensor-coupled channels. This allows us to readily obtain the high momentum distribution, for all partial waves, of a back-to-back correlated nucleon pair in nuclear matter. We find that the probability of finding a high-momentum correlated neutron-proton pair is about 18 times that of a proton-proton one, as a result of the strong tensor force, thus confirming in an independent way previous results and measurements.

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I. Ruiz Simo, R. Navarro Perez, J. E. Amaro, E. Ruiz Arriola. 2017-08-02. Coarse graining the Bethe-Goldstone equation: nucleon-nucleon high momentum components. https://arxiv.org/abs/1708.00878

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