文摘
Two-particle angular correlations between trigger particles in the forward pseudorapidity range (rc">rmulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0370269315009533&_mathId=si2.gif&_user=111111111&_pii=S0370269315009533&_rdoc=1&_issn=03702693&md5=50991944959a5ad100c5360a61869b8d" title="Click to view the MathML source">2.5<|η|<4.0r hidden">) and associated particles in the central range (rc">rmulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0370269315009533&_mathId=si103.gif&_user=111111111&_pii=S0370269315009533&_rdoc=1&_issn=03702693&md5=b01ed631e008a411b364a8e6e4139d2d" title="Click to view the MathML source">|η|<1.0r hidden">) 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 (rc">rmulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0370269315009533&_mathId=si104.gif&_user=111111111&_pii=S0370269315009533&_rdoc=1&_issn=03702693&md5=f4ce2793cefb176f0b90ceb0fcccb1da" title="Click to view the MathML source">pTr hidden">) dependence in p-going (p–Pb) and Pb-going (Pb–p) configurations, with the Pb-going coefficients larger by about rc">rmulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0370269315009533&_mathId=si5.gif&_user=111111111&_pii=S0370269315009533&_rdoc=1&_issn=03702693&md5=10f74ce3ddd1cfa42ebdb4609bf9e05c" title="Click to view the MathML source">16±6%r hidden">, rather independent of rc">rmulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0370269315009533&_mathId=si104.gif&_user=111111111&_pii=S0370269315009533&_rdoc=1&_issn=03702693&md5=f4ce2793cefb176f0b90ceb0fcccb1da" title="Click to view the MathML source">pTr hidden"> within the uncertainties of the measurement. The data are compared with calculations using the AMPT model, which predicts a different rc">rmulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0370269315009533&_mathId=si104.gif&_user=111111111&_pii=S0370269315009533&_rdoc=1&_issn=03702693&md5=f4ce2793cefb176f0b90ceb0fcccb1da" title="Click to view the MathML source">pTr hidden"> and η dependence than observed in the data. The results are sensitive to the parent particle rc">rmulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0370269315009533&_mathId=si6.gif&_user=111111111&_pii=S0370269315009533&_rdoc=1&_issn=03702693&md5=a35fbe0e8280b9de20a9c07b54c2d804" title="Click to view the MathML source">v2r hidden"> and composition of reconstructed muon tracks, where the contribution from heavy flavour decays is expected to dominate at rc">rmulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0370269315009533&_mathId=si101.gif&_user=111111111&_pii=S0370269315009533&_rdoc=1&_issn=03702693&md5=ca005e5855bf7c0f4b342410a3237bb5" title="Click to view the MathML source">pT>2 GeV/cr hidden">.