Search for doubly-heavy dibaryons in the quark-delocalization color-screening model

Abstract

We perform a systemical investigation of the low-lying doubly-heavy dibaryon systems with strange $S=0$, isospin $I=0$, $1$, $2$ and the angular momentum $J=0$, $1$, $2$, $3$ in the quark delocalization color screening model. We find the effect of channel-coupling cannot be neglected in the study of the multi-quark systems. Due to the heavy flavor symmetry, the results of the doubly-charm and doubly-bottom dibaryon systems are similar with each other. Both of them have three bound states, the quantum numbers of which are $IJ=00$, $IJ=02$ and $IJ=13$, respectively. The energies are $4554$ MeV, $4741$ MeV, and $4969$ MeV respectively for the doubly-charm systems and $11219$ MeV, $11416$ MeV, and $11633$ MeV respectively for the doubly-bottom dibaryon systems. Besides, six resonance states are obtained, which are $IJ=00$ $N\Xi_{cc}$ and $N\Xi_{bb}$ with resonance mass of $4716$ MeV and $11411$ MeV respectively, $IJ=11$ $N\Xi^*_{cc}$ and $N\Xi^*_{bb}$ with resonance mass of $4757$ MeV and $11432$ MeV respectively, and $IJ=12$ $\Sigma_{c}\Sigma^*_{c}$ and $\Sigma_{b}\Sigma^*_{b}$ with resonance mass of $4949$ MeV and $11626$ MeV respectively. All these heavy dibaryons are worth searching for on experiments, although it will be a challenging work.