Binding Energy ofH3andn−d-Doublet Scattering Length with Charge-Dependent Forces

A simple model of an $S$-state separable $n-p$ and $n-n$ interaction, with a hard-shell repulsion in the singlet state, is applied to study the effect of the charge dependence of nuclear forces on the ${}_{}{}^3{}_{}{}^{}\mathrm{H}$ ground-state energy $E_T$, and on the $n-d$-doublet scattering length ${}_{}{}^2{}_{}{}^{}a$. Several values of the $n-n$-singlet scattering parameters - all within the range of recent experimental estimates - have been used in fixing the parameters of the $n-n$ interaction. All the resulting values of $E_T$ and ${}_{}{}^2{}_{}{}^{}a$ stay close to the Phillips line. This indicates that the charge dependence is not the factor which could help us in accounting for the new experimental values of ${}_{}{}^2{}_{}{}^{}a$ and $E_T$.