  We perform hybrid Monte Carlo simulation of lattice QCD with $N_f=2+1+1 $
optimal domain-wall quarks on the $32^3 \times 64 $ lattice with lattice
spacing $a \sim 0.06$ fm, and generate a gauge ensemble with physical $s$ and
$c$ quarks, and pion mass $\sim 280 $ MeV. Using 2-quark (meson) and 3-quark
(baryon) interpolating operators, the mass spectra of the lowest-lying states
containing $s$ and $c$ quarks ($D_s$ and $\Omega_c$) are extracted
\cite{Chen:2017kxr}, which turn out in good agreement with the high energy
experimental values, together with the predictions of the charmed baryons which
have not been observed in experiments. For the five new narrow $\Omega_c$
states observed by the LHCb Collaboration \cite{Aaij:2017nav}, the lowest-lying
$\Omega_c(3000)$ agrees with our predicted mass $3015(29)(34)$ MeV of the
lowest-lying $\Omega_c$ with $J^P = 1/2^{-}$. This implies that the $ J^P $ of
$ \Omega_c(3000) $ is $ 1/2^- $.
