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Chiral Symmetry and Three-Nucleon Forces

J. L. Friar·D. Hüber·U. van Kolck
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Abstract

After a brief review of the role three-nucleon forces play in the few-nucleon systems, the chiral-perturbation-theory approach to these forces is discussed. Construction of the (nominal) leading- and subleading-order Born terms and pion-rescattering graphs contributing to two-pion-exchange three-nucleon forces is reviewed, and comparisons are made of the types of such forces that are used today. It is demonstrated that the short-range $c$-term of the Tucson-Melbourne force is unnatural in terms of power counting and should be dropped. The class of two-pion-exchange three-nucleon forces then becomes rather uniform.

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J. L. Friar, D. Hüber, U. van Kolck. 1998-09-22. Chiral Symmetry and Three-Nucleon Forces. https://doi.org/10.1103/physrevc.59.53

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