  We investigate the charmed baryon mass spectrum using the relativistic heavy
quark action on 2+1 flavor PACS-CS configurations previously generated on $32^3
\times 64$ lattice. The dynamical up-down and strange quark masses are set to
the physical values by using the technique of reweighting to shift the quark
hopping parameters from the values employed in the configuration generation. At
the physical point, the lattice spacing equals $a^{-1}=2.194(10)$ GeV and the
spatial extent $L=2.88(1)$ fm. Our results for the charmed baryon masses are
consistent with experiments except for $\Xi_{cc}$, which has only weak
experimental evidence yet. We also predict mass values for other doubly and
triply charmed baryons.
