Forward-central two-particle correlations in p–Pb collisions with ALICE at the LHC

Abstract

We present the results of measurements of two-particle angular correlations between trigger particles reconstructed in the ALICE Forward Muon Spectrometer (−4.0<η<−2.5) and associated particles reconstructed in the central barrel detectors (|η|<1.0) in p–Pb collisions at a nucleon-nucleon center-of-mass energy of 5.02 TeV. At low transverse momentum (pT), the reconstructed trigger particles mainly originate from weak decays of primary pions and kaons, whereas at high pT, they originate mainly from the decay of heavy-flavor particles. The ridge structure elongated in the η-direction, discovered recently in p–Pb collisions, is found to persist to the pseudorapidity ranges studied here. The second-order Fourier coefficients of muons are extracted after subtracting the correlations obtained in low-multiplicity events from those in high-multiplicity events. The ratio of coefficients in the Pb-going and p-going directions is presented as a function of pT, and the coefficients are observed to have a similar pT dependence in both directions with the Pb-going coefficients larger by 16±6%. The results are compared with calculations from a multi-phase transport model.