Effective theory of the triton Original Research Article

We apply the effective field theory approach to the three-nucleon system. In particular, we consider S=1/2 neutron–deuteron scattering and the triton. We show that in this channel a unique nonperturbative renormalization takes place which requires the introduction of a single three-body force at leading order. With one fitted parameter we find a good description of low-energy data. Invariance under the renormalization group explains some universal features of the three-nucleon system — such as the Thomas and Efimov effects and the Phillips line — and the origin of SU(4) symmetry in nuclei.