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Short-range three-nucleon forces and low-energy constants

J. Adam, Jr.·M. T. Pena·A. Stadler
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Abstract

The 3N forces due to pi-rho, pi-sigma and pi-omega exchanges following from the nucleon Born diagrams and diagrams with an intermediate N^{*}(1440) are re-analyzed. The cancellation between pi-sigma and pi-omega forces is rather sensitive to the values of the coupling constants and to the form of the piNN vertex. Experimental uncertainties in the parameters of the TM pi-pi potential are assessed. They lead to uncertainties in theoretical predictions of the triton binding energy of about 0.4 MeV. The low-energy limit of pi-sigma and pi-omega potentials is performed. It defines the coupling constants of effective contact piNNNN vertices, which are compared with the corresponding contact vertices of Chiral Perturbation Theory.

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J. Adam, Jr., M. T. Pena, A. Stadler. 2003-08-11. Short-range three-nucleon forces and low-energy constants. https://doi.org/10.1103/physrevc.69.034008

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