Doubly charmed pentaquark states in QCD sum rules

Abstract

We have studied the mass spectra of doubly charmed pentaquark states in the ${\Lambda }_c^{(\ast )}{D}^{(\ast )}$ and ${\Sigma }_c^{(\ast )}{D}^{(\ast )}$ channels with $J^P=1/2^{\pm }$, $3/2^{\pm }$ and $5/2^{\pm }$ within the framework of QCD sum rules. We use the parity projected sum rules to separate the contributions of negative and positive parities from the two-point correlations induced by the pentaquark interpolating currents. Our results show that the bound states of $P_{cc}$ pentaquarks may exist in the ${\Lambda }_{c}D({\frac{1}{2}}^{-})$, ${\Sigma }_{c}D({\frac{1}{2}}^{-})$, ${\Sigma }_c{D}^{\ast }({\frac{3}{2}}^{-})$, ${\Lambda }_c^{\ast }D({\frac{3}{2}}^{-})$, ${\Lambda }_c^{\ast }{D}^{\ast }({\frac{5}{2}}^{-})$ channels with negative-parity and ${\Sigma }_{c}D({\frac{1}{2}}^{+})$, ${\Sigma }_c{D}^{\ast }({\frac{3}{2}}^{+})$, ${\Sigma }_c^{\ast }D({\frac{3}{2}}^{+})$ channels with positive-parity, since their masses are predicted to be lower than the corresponding meson-baryon thresholds. However, they are still allowed to decay into the ${\Xi }_{cc}^{(\ast )}\pi$ final states via strong interaction. The triply charged $P_{cc}^{+++}(ccuu\bar{d})$ and neutral $P_{cc}^0(ccdd\bar{u})$ in the isospin quartet would definitely be pentaquark states due to their exotic charges. We suggest searching for these characteristic doubly charmed pentaquark signals in the $P_{cc}^{+++}\to {\Xi }_{cc}^{(\ast )++}{\pi }^{+}/{\rho }^{+}$, ${\Sigma }_c^{(\ast )++}{D}^{(\ast )+}$ and $P_{cc}^0\to {\Xi }_{cc}^{(\ast )+}{\pi }^{-}/{\rho }^{-}$, ${\Sigma }_c^{(\ast )0}{D}^{(\ast )0}$ decays in the near future.

Comments: 25 pages, 5 figures. Accepted by Physical Review D