A narrow $DNN$ quasi-bound state

The energies and widths of $DNN$ quasi-bound states with isospin I=1/2 are evaluated in two methods, the fixed center approximation to the Faddeev equation and the variational method approach to the effective one-channel Hamiltonian. The $DN$ interactions are constructed so that they dynamically generate the ${\mathrm{\Lambda }}_c(2595)$ (I=0, $J^{\pi }=1\mathrm{/}{2}^{-}$) resonance state. We find that the system is bound by about 250 MeV from the $DNN$ threshold, $\sqrt{s} \sim 3500$MeV\mathrm{.}Itswidthincludingboththemesonicdecayandthe$D$absorption,isestimatedtobeabout20-40MeV\mathrm{.}TheI=0$DN$pairinthe$DNN$systemisfoundtoformaclusterthatissimilartothe$\Lambda_c(2595)$.