Λ c + production in pp collisions at √s=7 TeV and in p-Pb collisions at √sNN=5.02 TeV

Research output: Contribution to journalArticle

Abstract

The pT-differential production cross section of prompt Λc + charmed baryons was measured with the ALICE detector at the Large Hadron Collider (LHC) in pp collisions at s=7 TeV and in p-Pb collisions at sNN=5.02 TeV at midrapidity. The Λc + and Λ¯ c ¯ were reconstructed in the hadronic decay modes Λc + → pK−π+, Λc + → pKS 0 and in the semileptonic channel Λc + → e+νeΛ (and charge conjugates). The measured values of the Λc +/D0 ratio, which is sensitive to the c-quark hadronisation mechanism, and in particular to the production of baryons, are presented and are larger than those measured previously in different colliding systems, centre-of-mass energies, rapidity and pT intervals, where the Λc + production process may differ. The results are compared with the expectations obtained from perturbative Quantum Chromodynamics calculations and Monte Carlo event generators. Neither perturbative QCD calculations nor Monte Carlo models reproduce the data, indicating that the fragmentation of heavy-flavour baryons is not well understood. The first measurement at the LHC of the Λc + nuclear modification factor, RpPb, is also presented. The RpPb is found to be consistent with unity and with that of D mesons within the uncertainties, and consistent with a theoretical calculation that includes cold nuclear matter effects and a calculation that includes charm quark interactions with a deconfined medium.[Figure not available: see fulltext.] © 2018, The Author(s).

Details

Authors
Organisations
External organisations
  • University of California, Berkeley
  • Utrecht University
  • Variable Energy Cyclotron Centre
  • Nuclear Physics Institute, ASCR
  • Panjab University
  • CERN
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Subatomic Physics

Keywords

  • Heavy Ion Experiments, Quark gluon plasma
Original languageEnglish
Article number2018:108
JournalJournal of High Energy Physics
Volume2018
Issue number4
Publication statusPublished - 2018 Apr 1
Publication categoryResearch
Peer-reviewedYes

Bibliographic note

Export Date: 2 July 2018