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

Abstract

The recent experimental measurements on pp collisions at s=5.02TeV have shown a very large production of heavy baryons corresponding to a Λc/D0 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 Λc/D∼O(1) in AA collisions at RHIC energy. We calculate the heavy baryon/meson ratio and the pT spectra of charmed hadrons with and without strangeness content: D0, Ds, Λc+, Ξc and Ωc in pp collisions at top LHC energies, finding a satisfactory result for the measured Λc+/D0 and the Ξc/D0. At variance with other approaches a coalescence approach predicts also a significant production of Ωc such that Ωc/D0∼O(10−1).