The $s$-wave asymptotic normalization constants $C_0$(${}_{}{}^3{}_{}{}^{}\mathrm{H}$) and $C_0$(${}_{}{}^3{}_{}{}^{}\mathrm{H}$) are calculated for the Reid soft-core potential. The Coulomb effect is taken into account for ${}_{}{}^3{}_{}{}^{}\mathrm{He}$. $C_0\left({}_{}{}^3{}_{}{}^{}\mathrm{He}\right)=1.765\mathrm{}$ and $C_0\left({}_{}{}^3{}_{}{}^{}\mathrm{H}\right)=1.706\mathrm{}$ have been obtained. In ${}_{}{}^3{}_{}{}^{}\mathrm{He}$ (${}_{}{}^3{}_{}{}^{}\mathrm{H}$), about 60% of the contribution is due to the transition from the $\mathrm{pp}$ ($\mathrm{nn}$) ${}_{}{}^1{}_{}{}^{}S_0^{}{}_{}{}^{}$ state of a pair in one set of coordinates to the $\mathrm{np}{}_{}{}^3{}_{}{}^{}D_1^{}{}_{}{}^{}$ state of another set.

• Received 18 July 1980

DOI:https://doi.org/10.1103/PhysRevLett.45.1386