Charge separation relative to the reaction plane in Pb-Pb collisions at \(\sqrt{s_{NN}}\)= 2.76 TeV

Abstract

Measurements of charge dependent azimuthal correlations with the ALICE detector at the LHC are reported for Pb-Pb collisions at \(\sqrt{s_{NN}}\) = 2.76 TeV. Two- and three-particle charge-dependent azimuthal correlations in the pseudo-rapidity range \(|\eta | < 0.8\) are presented as a function of the collision centrality, particle separation in pseudo-rapidity, and transverse momentum. A clear signal compatible with the expectation of a charge-dependent separation relative to the reaction plane is observed, which shows little or no collision energy dependence when compared to measurements at RHIC energies. Models incorporating effects of local parity violation in strong interactions fail to describe the observed collision energy dependence.