Long-range two-particle correlations with K0S and Lambda in pPb and PbPb collisions

Collaboration
2014
19 pages
Report number:
  • CMS-PAS-HIN-14-002
Experiments:

Citations per year

20122013201401
Abstract:
Measurements of two-particle angular correlations between identified strange hadrons (KS0\text{K}_{\text{S}}^{0} and Λ\Lambda/Λ\overline{\Lambda}) and unidentified charged particles, emitted in pPb collisions, are presented over a wide range in pseudorapidity and full azimuth. The data, corresponding to an integrated luminosity of approximately 35nb1^{-1}, were collected during the 2013 LHC pPb run at a nucleon-nucleon center-of-mass energy of 5.02TeV by the CMS experiment. The results are compared to 2.76TeV semi-peripheral PbPb collision data, collected during the 2011 PbPb run, covering a similar range of particle multiplicities. The KS0\text{K}_{\text{S}}^{0} and Λ\Lambda/Λ\overline{\Lambda} are reconstructed via their topological secondary decays. The observed long-range correlations are characterized by the second-order (v2v_2) and third-order (v3v_3) anisotropy harmonics of KS0\text{K}_{\text{S}}^{0} and Λ\Lambda/Λ\overline{\Lambda}, which are studied as a function of particle multiplicity and transverse momentum. For high-multiplicity pPb events, a particle-species dependence of v2v_2 and v3v_3 is observed. Divided by the number of constituent quarks, the v2v_2 and v3v_3 harmonics of KS0\text{K}_{\text{S}}^{0} and Λ\Lambda/Λ\overline{\Lambda} as a function of kinetic energy per quark fall on the same curve within 10--15%\% for each multiplicity class. This scaling is better than that observed in peripheral PbPb collisions.
Note:
  • Preliminary results
  • Data
  • particle: multiplicity
  • correlation: long-range
  • angular correlation: two-particle
  • quark: constituent
  • transverse momentum dependence
  • correlation function: (charged particle strange particle)
  • CERN LHC Coll
  • anisotropy
  • rapidity dependence