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Accurate Nucleon-Nucleon Potential Based upon Chiral Perturbation Theory

D. R. Entem·R. Machleidt
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Abstract

We present an accurate nucleon-nucleon ($NN$) potential based upon chiral effective Lagrangians. The model includes one- and two-pion exchange contributions up to chiral order three. We show that a quantitative fit of the $NN$ $D$-wave phase shifts requires contact terms (which represent the short range force) of order four. Within this framework, the $NN$ phase shifts below 300 MeV lab. energy and the properties of the deuteron are reproduced with high-precision. This chiral $NN$ potential represents a reliable starting point for testing the chiral effective field theory approach in exact few-nucleon and microscopic nuclear many-body calculations. An important implication of the present work is that the chiral $2π$ exchange at order four is of crucial interest for future chiral $NN$ potential development.

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D. R. Entem, R. Machleidt. 2001-08-24. Accurate Nucleon-Nucleon Potential Based upon Chiral Perturbation Theory. https://doi.org/10.1016/s0370-2693(01)01363-6

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