Abstract
The production cross section of prompt $\mathrm{\Lambda_{c}^{+}}$ charm baryons was measured with the ALICE detector at the LHC at midrapidity in proton-proton (pp) and proton-lead (p-Pb) collisions at a centre-of-mass energy per nucleon pair of $\sqrt{s_\mathrm{NN}} = 5.02$ TeV. The $\mathrm{\Lambda_{c}^{+}}$ and $\rm {\overline{\Lambda}{}_c^-}$ baryons were reconstructed in the hadronic decay channels $\rm \Lambda_{c}^{+} \rightarrow p K^{-}\pi^{+}$ and $\rm \Lambda_{c}^{+}\to p K^{0}_{S}$ and respective charge conjugates. The measured differential cross sections as a function of transverse momentum ($p_{\rm T}$) and the $p_{\rm T}$-integrated $\mathrm{\Lambda_{c}^{+}}$ production cross section in pp and in p-Pb collisions are presented. The $\mathrm{\Lambda_{c}^{+}}$ nuclear modification factor ($R_\mathrm{pPb}$), calculated from the cross sections in pp and in p-Pb collisions, is presented and compared with the $R_\mathrm{pPb}$ of D mesons. The $\mathrm {\Lambda_{c}^{+}}/\mathrm {D^0}$ ratio is also presented and compared with the light-flavour baryon-to-meson ratios p$/\pi$ and $\Lambda /\mathrm {K^0_S}$, and measurements from other LHC experiments. The results are compared to predictions from model calculations and Monte Carlo event generators.
Highlights
In hadronic collisions, heavy quarks are created predominantly in hard scattering processes, and the measurement of charm and beauty hadron production is a powerful test of perturbative quantum chromodynamics calculations
This paper presents the measurement of the pT -differential production cross section of charm
The particle identification (PID) selections for all analyses were performed utilising the Bayesian method for combining the time projection chamber (TPC) and TOF signals, as described in Ref. [90]
Summary
Heavy quarks (charm and beauty) are created predominantly in hard scattering processes, and the measurement of charm and beauty hadron production is a powerful test of perturbative quantum chromodynamics (pQCD) calculations. Theoretical predictions based on the QCD factorization approach describe the heavy-flavor hadron production cross section as a convolution of parton distribution functions, parton hard-scattering cross sections, and fragmentation functions. B-meson production cross sections in pp collisions at centerof-mass energies between 200 GeV and 13 TeV at RHIC [1], Tevatron [2,3,4], and the LHC [5,6,7,8,9] are generally described within uncertainties by perturbative calculations at next-toleading order with next-to-leading-log resummation, such as the general-mass variable-flavor-number scheme + c production cross section relative to D mesons provide insight into the hadronization of charm quarks into baryons.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have