Low-lying di-hadronic states in relativistic harmonic model

Di-hadronic molecules such as di-meson, meson-baryon and di-baryon states are studied in the relativistic confinement model. We have computed the binding energy of the di-hadronic systems like $K-N$, $\mathrm{\Pi }-N$, $\rho -N$ etc., as penta-quark states, 2$\pi$, $\rho -\rho$, $K-K^{\ast }$, $K^{\ast }-K^{\ast }$, $D-D^{\ast }$ etc. as tetra-quark states and $N-N$, $N-\mathrm{\Delta }$, $\mathrm{\Delta }-\mathrm{\Delta }$ etc. as di-baryonic states using a molecular interaction provided by asymptotic expression of the confined gluon exchange potential. We find the lowest penta-quark state lies in the energy range of 1.180 - 2.247 GeV as predicted by other theoretical models. The exotic states such as $f0(0.982)$, $h1(1.170)$, $f0(1.70)$, $f2 (1.565)$,$f2 (1.95)$,$\psi(4.040)$ etc. are identified as the di-mesonic hadron molecules. The low-lying di-baryon molecular states found to be in the range of 1.990-2.907 GeV with their binding energies lying between 112-120 MeV.