Charmed-baryon production and hadronization studies with ALICE

About

The measurements of the charmed baryons are fundamental to investigate charm-quark production and hadronization mechanisms in different collision systems. Recent measurements of charm-baryon production in small systems at LHC energies show a baryon-over-meson ratio significantly higher than that in e$^{+}$e$^{-}$ and e$^{\pm}$p collisions, and higher than expectations from Monte Carlo generators, tuned to reproduce these measurements, suggesting a violation of the universality of the fragmentation of charm in different collision systems. Various mechanisms are recently being considered in the theory community to describe the measurements, such as multi-parton interactions, colour reconnection, ropes, or statistical hadronization approaches. In nucleus-nucleus collisions, where a hot and dense Quark-Gluon Plasma (QGP) forms and collectively expands, the enhancement of baryon-to-meson ratios is predicted by theoretical models in which heavy quarks hadronize by coalescence with light quarks from the plasma. Measurements of $\Lambda_{\rm c}$ production in nucleus-nucleus collisions hint to a larger ratio to D mesons, with respect to the case of pp collisions. Furthermore, the measurement of open heavy flavours as a function of multiplicity in pp and p-Pb collisions provides important information to understand how the possible presence of collective effects could modify the production of heavy-flavour hadrons. The analysis of different charm baryon species, such as $\Sigma_{\rm c}$ and $\Xi_{\rm c}$, give further insight into the study of the charm hadrons production in all systems.

In this talk, we present measurements of $\Lambda_{\rm c}$, $\Xi_{\rm c}$ and $\Sigma_{\rm c}$ baryons performed with the ALICE detector at mid-rapidity in pp collisions at various collision energies. The $\Lambda_{\rm c}/ {\rm D}^{0}$ ratio measured in different collision systems and its multiplicity dependency from pp to p-Pb and Pb-Pb collisions will be shown. The $R_{\rm pPb}$ and the…