Charm production and hadronisation in pp and p--Pb collisions at $\sqrt{s_{\rm NN}} = $ 5.02 TeV at the LHC with ALICE

TL;DR

This paper presents measurements of charm hadron production and ratios in pp and p--Pb collisions at 5.02 TeV, providing insights into charm hadronisation mechanisms and potential nuclear matter effects at the LHC.

Contribution

It reports the first baryon-to-meson yield ratio measurements for $ m \Lambda^{+}_{c}/ m D^{0}$ at low transverse momentum in p--Pb collisions, advancing understanding of charm hadronisation.

Findings

Charm production cross sections are measured at midrapidity.

First $ m \Lambda^{+}_{c}/ m D^{0}$ ratio at low $p_T$ in p--Pb collisions.

Comparison with Monte Carlo models highlights hadronisation effects.

Abstract

Production measurements of charm hadrons, particularly the yield ratios of different hadron species as a function of the transverse momentum, are important to study the charm hadronisation mechanism. In this contribution, measurements of $\rm D^{0}$, $\rm D^{+}$, and $\rm D^{+}_{\rm s}$ meson production, as well as $\Lambda^{+}_{\rm c}$-baryon production at midrapidity in pp and p--Pb collisions at $\sqrt{s_{\rm NN}} = $ 5.02 TeV with ALICE will be discussed. The measurements will be compared with predictions from Monte Carlo event generators and theoretical calculations. In addition, the first baryon-to-meson yield ratio measurements for $\Lambda^{+}_{\rm c}/\rm D^{0}$ down to $p_{\rm T}$ = 0 in p--Pb collisions will be discussed. In such collisions, a modification of the hadronisation mechanisms could be present due to cold nuclear matter effects and possible collective phenomena. Finally, measurements of charm fragmentation fractions and the total charm production cross section per unit of rapidity at midrapidity, in pp and p--Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV at the LHC, will be presented.