Hidden-charm pentaquarks and $P_c$ states

Understand

Recently, the LHCb Collaboration reported three $P_c$ states in the ${J/\psi}p$ channel.

• We systematically study the mass spectrum of the hidden charm pentaquark in the framework of an extended chromomagnetic model.
• For the $nnnc\bar{c}$ pentaquark with $I=1/2$, we find that (i) the lowest state is $P_{c}(4327.0,1/2,1/2^{-})$ [We use $P_{c}(m,I,J^{P})$ to denote the $nnnc\bar{c}$ pentaquark], which corresponds to the $P_{c}(4312)$.
• Its dominant decay mode is $\Lambda_{c}\bar{D}^{*}$.