Potential of discovering ${\mathrm{\Xi }}_{cc}^{+}$ in ${\mathrm{\Lambda }}_b$ decays

We propose to search for ${\mathrm{\Xi }}_{cc}^{+}$ in the decay ${\mathrm{\Lambda }}_b\to {\mathrm{\Xi }}_{cc}^{+}{D}^{-}$, which serves as a tagged and reconstructible source of ${\mathrm{\Xi }}_{cc}^{+}$, providing an experimentally clean environment for its discovery. A possible fully charged final state is $[(p{K}^{-}{K}^{-}{\pi }^{+}{)}_{{\mathrm{\Xi }}_c^0}{\pi }^{+}{]}_{{\mathrm{\Xi }}_{cc}^{+}}(K^{+}{\pi }^{-}{\pi }^{-}{)}_{D^{-}}$, where the subscripts indicate the parent hadron in the decay chain. We estimate the branching fraction to be $\mathcal{B}({\mathrm{\Lambda }}_b\to {\mathrm{\Xi }}_{cc}^{+}{D}^{-})=(5.1\pm 3.9)\times {10}^{-4}$, while the fully charged final state corresponds to an effective branching fraction of order ${10}^{-8}$. These results indicate that LHCb has the potential to discover the ${\mathrm{\Xi }}_{cc}^{+}$. The prospects for observing ${\mathrm{\Omega }}_{cc}^{+}$ are also briefly discussed.