CMS logoCMS event Hgg
Compact Muon Solenoid
LHC, CERN

CMS-PAS-HIN-21-004
Study of charm hadronization with prompt $ \Lambda_c^+ $ baryons in proton-proton and lead-lead collisions at $ \sqrt {\smash [b]{s_{_{\mathrm {NN}}}}}= $ 5.02 TeV
Abstract: The production of prompt $ \Lambda_c^+ $ baryons is measured via the exclusive decay channel $ \Lambda_c^+ \to \mathrm{p} \mathrm{K}^- \pi^+ $ at a center-of-mass energy per nucleon pair of 5.02 TeV using 252 nb$^{-1}$ proton-proton (pp) and 0.607 nb$^{-1}$ lead-lead (PbPb) collisions collected at the CERN LHC in 2017 and 2018, respectively. The measurements are performed within the $ \Lambda_c^+ $ rapidity interval $ |y| < $ 1.0 with transverse momentum ($ p_\mathrm{T} $) ranges of 3-30 and 6-40 $ \mathrm{GeV}/c $ for pp and PbPb collisions, respectively. Compared to pp collisions scaled by the number of nucleon-nucleon interactions, the observed yields of $ \Lambda_c^+ $ with $ p_\mathrm{T} > $ 10 GeV/$c$ are strongly suppressed in PbPb collisions. The level of suppression depends significantly on both the collision centrality and the $ p_\mathrm{T} $ of the $ \Lambda_c^+ $ baryon. The $ \Lambda_c^+/\mathrm{D}^0 $ production ratio in PbPb collisions is consistent with the result in pp collisions for $ p_\mathrm{T} > $ 10 GeV/$c$, suggesting that the coalescence process of hadronization is not significant for PbPb collisions in the higher $ p_\mathrm{T} $ region.
CMS Publications
Compact Muon Solenoid
LHC, CERN