| 摘要: |
We investigate the consequences of heavy quark spin symmetry (HQSS) on hidden-charm pentaquark P-c states. As has been proposed before, assuming the P-c(4440) and the P-c(4457) as S-wave (D) over bar*Sigma(c) molecules, seven hadronic molecular states composed of (D) over bar Sigma(c), (D) over bar Sigma(*)(c), (D) over bar*Sigma(c), and (D) over bar*Sigma(*)(c) can be obtained, with the (D) over bar Sigma(c) molecule corresponding to the P-c(4312). These seven states can decay into J/psi N and eta N-c, and we use HQSS to predict ratios of partial widths of the S-wave decays. For the decays into J/psi N, it is found that among all six P-c molecules with spin 1/2 or 3/2, at least four states decay much more easily into the J/psi N than the P-c(4312), and two of them couple dominantly to the (D) over bar*Sigma(c). While no significant peak around the (D) over bar*Sigma(*)(c) threshold is found in the J/psi p distribution, these higher P-c states either are produced with lower rates or some special production mechanism for the observed P-c states might play an important role, such as an intricate interplay between the production of pentaquarks and triangle singularities. |
