Search for the chiral magnetic effect at the LHC with the CMS experiment

Tu Z., Sirunyan A. M., Tumasyan A., Adam W., Ambrogi F., Asilar E., ...More

NUCLEAR PHYSICS A, vol.982, pp.527-530, 2019 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 982
  • Publication Date: 2019
  • Doi Number: 10.1016/j.nuclphysa.2018.08.032
  • Journal Name: NUCLEAR PHYSICS A
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.527-530
  • Middle East Technical University Affiliated: Yes


Searches for the chiral magnetic effect (CME) using charge-dependent azimuthal correlations with respect to event planes are presented in PbPb collisions at 5.02 TeV and pPb collisions at 5.02 and 8.16 TeV, with the CMS experiment at the LHC. The azimuthal correlations with respect to the second- and third-order event planes are explored as a function of pseudorapidity, transverse momentum, and event multiplicity, which provides new insights into the underlying background correlations. By employing an event-shape engineering technique, a linear dependence of charge-dependent correlations on the second-order anisotropy flow (nu(2)) is observed, and the upper limits on the nu(2)-independent fraction, which is directly related to the CME signal, are obtained at 95% confidence level for both pPb and PbPb collisions. These results provide strong constraints on the search for the chiral magnetic effect at LHC energies, and establish new guidelines for searches in future experiments.