Identifying the ${\mathrm{\Xi }}_c^0$ baryons observed by LHCb as $P$-wave ${\mathrm{\Xi }}_c^{\mathrm{\prime }}$ baryons

We systematically study mass spectra and decay properties of $P$-wave ${\mathrm{\Xi }}_c^{\mathrm{\prime }}$ baryons of the $SU(3)$ flavor ${\mathbf{6}}_F$, using the methods of QCD sum rules and light-cone sum rules within the framework of heavy quark effective theory. Our results suggest that the three excited ${\mathrm{\Xi }}_c^0$ baryons recently observed by LHCb can be well explained as $P$-wave ${\mathrm{\Xi }}_c^{\mathrm{\prime }}$ baryons: the ${\mathrm{\Xi }}_c(2923{)}^0$ and ${\mathrm{\Xi }}_c(2939{)}^0$ are partner states of $J^P = 1/2^-$and$3/2^-$respectively,bothofwhichcontainone$\lambda$-mode orbital excitation; the ${\mathrm{\Xi }}_c(2965{)}^0$ has $J^P=3\mathrm{/}{2}^{-}$, and also contains one $\lambda$-mode orbital excitation. We propose to search for another $P$-wave ${\mathrm{\Xi }}_c^{\mathrm{\prime }}$ state of $J^P=5\mathrm{/}{2}^{-}$ in the ${\mathrm{\Lambda }}_{c}K\mathrm{/}{\mathrm{\Xi }}_c\pi$ mass spectral in future experiments. Its mass is about $56_{-35}^{+30}$ MeV larger than the ${\mathrm{\Xi }}_c(2965{)}^0$, and its width is about $18.1_{-8.3}^{+19.7}$ MeV.