The measurement of heavy-flavour baryon production in hadronic collisions provides crucial information on non-perturbative dynamics of charm quark production and hadronisation. The fraction of charm quarks hadronising to baryons and mesons can be probed with ‘baryon-to-meson’ production ratios, and it is often assumed that the fragmentation of charm quarks to charmed hadrons is universal among collision systems. However, a new measurement of charmed baryon production challenges this assumption.
The production of the charmed baryon Λ+c and the baryon-to-meson production ratio Λ+c/D0 has been measured as a function of transverse momentum in pp and p-Pb collisions at √sNN = 5.02 TeV. The Λ+c/D0 ratios show a strong pT dependence and are significantly larger than predictions driven by charmed hadron fragmentation in e+e- and ep collisions, indicating that charmed baryons are produced more frequently produced in hadronic collisions than e+e- and e-p collisions. The similarity between the light flavour and charm baryon-to-meson ratios also provide indications, for the first time, of common hadronization mechanisms for light-flavour and charmed baryons. In addition, these measurements provide a crucial reference for future measurements in Pb-Pb collisions.
ALICE Collaboration 2020 https://arxiv.org/abs/2011.06078
ALICE Collaboration 2020 https://arxiv.org/abs/2011.06079