Inhaltszusammenfassung

A measurement of the production of prompt Λ+c baryons in Pb-Pb collisions at sNN‾‾‾‾√=5.02 TeV with the ALICE detector at the LHC is reported. The Λ+c and Λ⎯⎯⎯⎯−c were reconstructed at midrapidity (|y|<0.5) via the hadronic decay channel Λ+c→pK0S (and charge conjugate) in the transverse momentum and centrality intervals 6<pT<12 GeV/c and 0-80%. The Λ+c/D0 ratio, which is sensitive to the charm quark hadronisation mechanisms in the medium, is measured and found to be larger than the ratio meas...A measurement of the production of prompt Λ+c baryons in Pb-Pb collisions at sNN‾‾‾‾√=5.02 TeV with the ALICE detector at the LHC is reported. The Λ+c and Λ⎯⎯⎯⎯−c were reconstructed at midrapidity (|y|<0.5) via the hadronic decay channel Λ+c→pK0S (and charge conjugate) in the transverse momentum and centrality intervals 6<pT<12 GeV/c and 0-80%. The Λ+c/D0 ratio, which is sensitive to the charm quark hadronisation mechanisms in the medium, is measured and found to be larger than the ratio measured in minimum-bias pp collisions at s√=7 TeV and in p-Pb collisions at sNN‾‾‾‾√=5.02 TeV. In particular, the values in p-Pb and Pb-Pb collisions differ by about two standard deviations of the combined statistical and systematic uncertainties. The Λ+c/D0 ratio is also compared with model calculations including different implementations of charm quark hadronisation. The measured ratio is reproduced by models implementing a pure coalescence scenario, while adding a fragmentation contribution leads to an underestimation. The Λ+c nuclear modification factor, RAA, is also presented. The measured values of the RAA of Λ+c, Ds and non-strange D mesons are compatible within the combined statistical and systematic uncertainties. They show, however, a hint of a hierarchy (RD0AA<RDsAA<RΛ+cAA), conceivable with a contribution of recombination mechanisms to charm hadron formation in the medium. » weiterlesen» einklappen

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DDC Sachgruppe:
Physik