Hidden Charm Pentaquark $P_c(4380)$ and Doubly Charmed Baryon ${\Xi }_{cc}^{\ast }(4380)$ as Hadronic Molecule States

Abstract

We study hadronic molecular states in a coupled system of $J/\psi N-{\Lambda }_c{\bar{D}}^{(\ast )}-{\Sigma }_c^{(\ast )}{\bar{D}}^{(\ast )}$ in $I(J^P)=\frac{1}{2}({\frac{3}{2}}^{-})$ channel, using the complex scaling method combined with the Gaussian expansion method. We construct the potential including one pion exchange and one $D^{(\ast )}$ meson exchange with $S$-wave orbital angular momentum. We find that the both mass and width of the pentaquark $P_c(4380)$ can be reproduced within a reasonable parameter region, and that its main decay mode is ${\Lambda }_c{\bar{D}}^{\ast }$. We extend our analysis to a coupled system of ${\Lambda }_c{D}^{(\ast )}-{\Sigma }_c^{(\ast )}{D}^{(\ast )}$ in $I(J^P)=\frac{1}{2}({\frac{3}{2}}^{-})$ channel. We find that there exists a doubly charmed baryon of $ccqq\bar{q}$ type as a hadronic molecule, the mass and width of which are quite close to those of $P_c(4380)$.

Comments: 6 pages