ΣHypernuclei andΣ+-Proton Scattering

By analyzing the ${\Sigma }^{+}$-proton scattering data at low energies, it is found that the triplet $\Sigma$-nucleon interaction in the $I=\frac{3}{2}$ state is certainly not strong enough to support the formation of a particle-stable ${\Sigma }^{-}n$ or ${\Sigma }^{+}p$ system. The singlet $\Sigma$-nucleon interaction, on the other hand, could be quite strong, but it is probably still not sufficient to create a bound two-body $\Sigma$ hypernucleus. Also, because of the relative weakness of the triplet interaction, it can be concluded that a bound hypernucleus ${\Sigma }^{-}\mathrm{nn}$ very likely does not exist. Using the results obtained in this investigation, speculations are also made concerning the double-$\Sigma$ hypernuclear systems ${\Sigma }^{-}{\Sigma }^{-}n$ and ${\Sigma }^{-}{\Sigma }^{-}\mathrm{nn}$.