Search for the doubly charmed baryon $Ξ_{cc}^{+}$
A search for the doubly charmed baryon $Ξ_{cc}^{+}$ is performed through its decay to the $Λ_c^+ K^- π^+$ final state, using proton-proton collision data collected with the LHCb detector at centre-of-mass energies of 7, 8 and 13$\mathrm{\,Te\kern -0.1em V}$. The data correspond to a total integrated luminosity of $9\,\mathrm{fb}^{-1}$. No significant signal is observed in the mass range from 3.4 to 3.8$\mathrm{\,Ge\kern -0.1em V}/c^2$. Upper limits are set at $95\%$ credibility level on the ratio of the $Ξ_{cc}^{+}$ production cross-section times the branching fraction to that of $Λ_c^+$ and $Ξ_{cc}^{++}$ baryons. The limits are determined as functions of the $Ξ_{cc}^{+}$ mass for different lifetime hypotheses, in the rapidity range from 2.0 to 4.5 and the transverse momentum range from 4 to 15$\mathrm{\,Ge\kern -0.1em V}/c$.