Possible triple-charm molecular pentaquarks from $Ξ_{cc}D_1/Ξ_{cc}D_2^*$ interactions
In this work, we explore a systematic investigation on $S$-wave interactions between a doubly charmed baryon $Ξ_{cc}(3621)$ and a charmed meson in a $T$ doublet $(D_1,\,D_2^*)$. We first analyze the possibility for forming $Ξ_{cc}D_1/Ξ_{cc}D_2^*$ bound states with the heavy quark spin symmetry. Then, we further perform a dynamical study on the $Ξ_{cc}D_1/Ξ_{cc}D_2^*$ interactions within a one-boson-exchange model by considering both the $S$-$D$ wave mixing and coupled channel effect. Finally, our numerical results conform the proposals from the heavy quark spin symmetry analysis: the $Ξ_{cc}D_1$ systems with $I(J^P)=$ $0(1/2^+,\,3/2^+)$ and the $Ξ_{cc}D_2^*$ systems with $I(J^P)=$ $0(3/2^+,\,5/2^+)$ can possibly be loose triple-charm molecular pentaquarks. Meanwhile, we also extend our model to the $Ξ_{cc}\bar{D}_1$ and $Ξ_{cc}\bar D_2^*$ systems, and our results indicate the isoscalars of $Ξ_{cc}\bar{D}_1$ and $Ξ_{cc}\bar{D}_2^*$ can be possible molecular candidates.