Observation of new baryons in the ${\mathrm{\Xi }}_b^{-}{\pi }^{+}{\pi }^{-}$ and ${\mathrm{\Xi }}_b^0{\pi }^{+}{\pi }^{-}$ systems

The first observation and study of two new baryonic structures in the final state ${\mathrm{\Xi }}_b^0{\pi }^{+}{\pi }^{-}$ and the confirmation of the ${\mathrm{\Xi }}_b(6100{)}^{-}$ state in the ${\mathrm{\Xi }}_b^{-}{\pi }^{+}{\pi }^{-}$ decay mode are reported using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of 9${\mathrm{f}\mathrm{b}}^{-1}$. In addition, the properties of the known ${\mathrm{\Xi }}_b^{\ast 0}$, ${\mathrm{\Xi }}_b^{{}^{\mathrm{\prime }}-}$ and ${\mathrm{\Xi }}_b^{\ast -}$ resonances are measured with improved precision. The new decay mode of the ${\mathrm{\Xi }}_b^0$ baryon to the ${\mathrm{\Xi }}_c^{+}{\pi }^{-}{\pi }^{+}{\pi }^{-}$ final state is observed and exploited for the first time in these measurements.