$\Lambda_c^+$ production and baryon-to-meson ratios in pp and p-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV at the LHC

The prompt production of the charmed baryon $\Lambda_c^+$ and the $\Lambda_c^+$/D$^0$ production ratios were measured at midrapidity with the ALICE detector in pp and p-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV. These new measurements show a clear decrease of the Λ+c /D0 ratio with increasing transverse momentum ($p_{T}$) in both collision systems in the range 2 < $p_{T}$ < 12 GeV/$c$, exhibiting similarities with the light-flavour baryon-to-meson ratios p/$\pi$ and $\Lambda$/K$_S$. At low $p_{T}$, predictions that include additional colour-reconnection mechanisms beyond the leading-colour approximation; assume the existence of additional higher-mass charmed-baryon states; or include hadronisation via coalescence can describe the data, while predictions driven by charm-quark fragmentation processes measured in e$^+$e$^−$ and e-p collisions significantly underestimate the data. The results presented in this letter provide significant evidence that the QCD factorisation scheme, with the assumption of universal (colliding system independent) fragmentation, is not sufficient to describe charmed-baryon production in hadronic collisions at LHC energies.