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

The 3N forces due to π-ρ,π-σ, and π-ω exchanges following from the nucleon Born diagrams and diagrams with an intermediate N*(1440) are reanalyzed. The cancellation between π-σ and π-ω forces is rather sensitive to the values of the coupling constants and to the form of the πNN vertex. Experimental uncertainties in the parameters of the Tucson-Melbourne π-π 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 π-σ and π-ω potentials is performed. It defines the coupling constants of effective contact πNNNN vertices, which are compared with the corresponding contact vertices of chiral perturbation theory