Forward-central two-particle correlations in p-Pb collisions at \(\sqrt{s_{\rm NN}}\) = 5.02 TeV

Abstract

Two-particle angular correlations between trigger particles in the forward pseudorapidity range \(2.5 < |\eta| < 4.0\) and associated particles in the central range \(|\eta| < 1.0\) are measured with the ALICE detector in p-Pb collisions at a nucleon-nucleon centre-of-mass energy of 5.02 TeV. The trigger particles are reconstructed using the muon spectrometer, and the associated particles by the central barrel tracking detectors. In high-multiplicity events, the double-ridge structure, previously discovered in two-particle angular correlations at midrapidity, is found to persist to the pseudorapidity ranges studied in this Letter. The second-order Fourier coefficients for muons in high-multiplicity events are extracted after jet-like correlations from low-multiplicity events have been subtracted. The coefficients are found to have a similar transverse momentum \(p_{\rm T}\) dependence in p-going (p-Pb) and Pb-going (Pb-p) configurations, with the Pb-going coefficients larger by about \(16\pm6\)., rather independent of \(p_{\rm T}\) within the uncertainties of the measurement. The data are compared with calculations using the AMPT model, which predicts a different \(p_{\rm T}\) and \(\eta\) dependence than observed in the data. The results are sensitive to the parent particle \(v_2\) and composition of reconstructed muon tracks, where the contribution from heavy flavour decays are expected to dominate at \(p_{\rm T}>2\) GeV/\).\).