Speaker
Description
The study of charm quark hadrons is an important probe to the processes of hadronization of heavy quarks. More specifically, we present results on the production of $\Lambda_\mathrm{c}$ baryon, the nuclear modification factors ($R_\mathrm{AA}$), and the $\Lambda_\mathrm{c}/\mathrm{D}^{0}$ yield ratios at $\sqrt{s_{_{\mathrm{NN}}}} = 5.02$~TeV in proton-proton (pp) collisions and in different centrality regions in lead-lead (PbPb) collisions, using data recorded with the CMS detector in 2017 and 2018, respectively. The reported $R_\mathrm{AA}$ for $\Lambda_\mathrm{c}$ provides useful information regarding the energy loss mechanism of charm quark in the quark-gluon plasma. Its $p_\mathrm{T}$-dependence is similar to that of other charm and beauty hadrons but with its minimum shifted towards higher $p_\mathrm{T}$. Comparing the $\Lambda_\mathrm{c}/\mathrm{D}^{0}$ production ratio in pp and PbPb collisions suggests that coalescence as an hadronization process is not significant for $p_\mathrm{T} > 10$~GeV/c. The ratio becomes comparable to the measurements in $\mathrm{e^{+}e^{-}}$ collisions for $p_\mathrm{T} > 30$~GeV/c. We also present results of the $\Lambda_\mathrm{c}$ baryon and $\mathrm{D}^{0}$ meson production and their ratios in proton-lead (Pb) collisions at $\sqrt{s_{_{\mathrm{NN}}}} = 8.16$~TeV as a function of $p_\mathrm{T}$ and final-state multiplicity using the data recorded by the CMS experiment in 2016. We do not observe any significant multiplicity dependence for the baryon over meson ratio for charm hadrons. The difference between the results from charm quarks and that from light quarks, based on a previous study, suggests coalescence processes of heavy quarks saturate earlier than those of light quarks.
| Category | Experiment |
|---|---|
| Collaboration (if applicable) | CMS |
