Weak Decays of Doubly Charmed Baryons

The existence of doubly heavy baryons have not been well established in experiments so far. Searching for them is one of the important purposes at the Large Hadron Collider (LHC) where plenty of heavy quarks have been generated. In this Letter we study the weak decays of doubly charmed baryons, $\Xi_{cc}^{++}$ and $\Xi_{cc}^{+}$, using the light-front quark model to calculate the transition form factors and firstly considering the rescattering mechanism for the long-distance contributions to predict the corresponding branching fractions. Considering the predicted larger lifetime of $\Xi_{cc}^{++}$ than that of $\Xi_{cc}^{+}$, we find the processes of $\Xi_{cc}^{++}\to \Lambda_c^+K^-\pi^+\pi^+$, $\Xi_c^+\pi^+$ and $p D^0\pi^+$ are accessible with more possibilities at LHCb.