Charm hadrons in pp collisions at LHC energy within a coalescence plus fragmentation approach

Abstract The recent experimental measurements on pp collisions at s = 5.02 TeV have shown a very large production of heavy baryons corresponding to a Λ c / D 0 ratio of about 0.5. This ratio is about one order of magnitude larger than what measured in e + e − , ep collisions, and is larger of about a factor two respect to the forward rapidity ratio in pp collisions at LHC. We apply for the first time to pp collisions a quark coalescence plus fragmentation approach developed for AA collisions, assuming the formation of Hot QCD matter at finite temperature, which was able to correctly predict a Λ c / D ∼ O ( 1 ) in AA collisions at RHIC energy. We calculate the heavy baryon/meson ratio and the p T spectra of charmed hadrons with and without strangeness content: D 0 , D s , Λ c + , Ξ c and Ω c in pp collisions at top LHC energies, finding a satisfactory result for the measured Λ c + / D 0 and the Ξ c / D 0 . At variance with other approaches a coalescence approach predicts also a significant production of Ω c such that Ω c / D 0 ∼ O ( 10 − 1 ) .