Observation of $\Xi (1620{)}^0$ and evidence for $\Xi (1690{)}^0$ in ${\Xi }_c^{+}\to {\Xi }^{-}{\pi }^{+}{\pi }^{+}$ decays

Belle collaboration, M. Sumihama, I. Adachi +183

We report the first observation of the doubly-strange baryon $\Xi (1620{)}^0$ in its decay to ${\Xi }^{-}{\pi }^{+}$ via ${\Xi }_c^{+}\to {\Xi }^{-}{\pi }^{+}{\pi }^{+}$ decays based on a $980{\mathrm{fb}}^{-1}$ data sa…