Probing new types of Pc states inspired by the interaction between an S -wave charmed baryon and an anticharmed meson in a T¯ doublet state

Inspired by the observations of three $P_c$ states, we systematically investigate interactions between an $S$-wave charmed baryon ${\mathcal{B}}_c^{(*)}={\mathrm{\Lambda }}_c/{\mathrm{\Sigma }}_c/{\mathrm{\Sigma }}_c^{*}$ and an anticharmed meson $\overline{T}={\overline{D}}_1/{\overline{D}}_2^{*}$ with the one-pion-exchange potential model and the one-boson-exchange potential model, and search for possible new types of $P_c$ states with the structures of ${\mathcal{B}}_c^{(*)}\overline{T}$. Both $S-D$ wave mixing and coupled channel effects are considered. Our results suggest that in some ${\mathcal{B}}_c^{(*)}\overline{T}$ systems there are ideal candidates of new types of $P_c$ states—i.e., the ${\mathrm{\Sigma }}_c{\overline{D}}_1$ state with $I\left(J^P\right)=1/2(1/2^{+})$, the ${\mathrm{\Sigma }}_c{\overline{D}}_2^{*}$ state with $I\left(J^P\right)=1/2(3/2^{+})$, the ${\mathrm{\Sigma }}_c^{*}{\overline{D}}_1$ state with $I\left(J^P\right)=1/2(1/2^{+})$, and the ${\mathrm{\Sigma }}_c^{*}{\overline{D}}_2^{*}$ states with $I\left(J^P\right)=1/2(1/2^{+},3/2^{+})$—and we suggest that these predicted new types of $P_c$ states can be detected in the process ${\mathrm{\Lambda }}_b^0\to \psi \left(2S\right)p{\pi }^{-}$. Meanwhile, we also extend our study to the interactions between an $S$-wave charmed baryon and a charmed meson in a $T$ doublet, and we predict a series of double-charm molecular pentaquarks.