Masses and strong decays of open charm hexaquark states $\hat{I}{\pounds }_c^{(\ast )}\hat{I}{\pounds }_c^{(\ast )}$

Abstract

Inspired by the recent discovery of the doubly charmed tetraquark state $T_{cc}^{+}$ by the LHCb Collaboration, we perform a systematic study of masses and strong decays of open charm hexaquark states $\hat{I}{\pounds }_c^{(\ast )}\hat{I}{\pounds }_c^{(\ast )}$. Taking into account heavy quark spin symmetry breaking, we predict several bound states of isospin $I=0$, $I=1$, and $I=2$ in the one boson exchange model. Moreover, we adopt the effective Lagrangian approach to estimate the decay widths of $\hat{I}{\pounds }_c^{(\ast )}\hat{I}{\pounds }_c^{(\ast )}\to \hat{I}{›}_c\hat{I}{›}_c$ and their relevant ratios via the triangle diagram mechanism, which range from a few MeV to a few tens of MeV. We strongly recommend future experimental searches for the $\hat{I}{\pounds }_c^{(\ast )}\hat{I}{\pounds }_c^{(\ast )}$ hexaquark states in the $\hat{I}{›}_c\hat{I}{›}_c$ invariant mass distributions.