Correlation among low-energy four-nucleon observables

We study the correlation among s-wave low-energy four-nucleon observables by using a simplified dispersion theoretic (N/D) approach. We find that the triton binding energy, its asymptotic normalization parameter, the deuteron exchange left-hand cut, and the nucleon-trinucleon (N-t) scattering length control the low-energy N-t system. The isospin one channel is insensitive to the asymptotic normalization parameter of the triton. The effective range function kcotδ for the isospin zero spin singlet N-t system has a pole whose position and residue are strongly correlated with the N-t scattering length. In this case the four-nucleon system (in our model) has an excited state whose binding energy and asymptotic normalization parameter are also correlated with the N-t scattering length.[NUCLEAR REACTIONS s-wave nucleon-trinucleon systems, spin-isospin channels, N/D approach, low-energy correlations.]