Multiplicity dependence of charged pion, kaon, and (anti)proton production at large transverse momentum in p–Pb collisions at √sNN=5.02 TeV

Abstract

The production of charged pions, kaons and (anti)protons has been measured at mid-rapidity (−0.5 <y <0) in p–Pb collisions at √sNN=5.02TeVusing the ALICE detector at the LHC. Exploiting particle identification capabilities at high transverse momentum (pT), the previously published pTspectra have been extended to include measurements up to 20GeV/cfor seven event multiplicity classes. The pTspectra for pp collisions at √s=7TeV, needed to interpolate a pp reference spectrum, have also been extended up to 20GeV/cto measure the nuclear modification factor (RpPb) in non-single diffractive p–Pb collisions. At intermediate transverse momentum (2 <pT<10GeV/c) the proton-to-pion ratio increases with multiplicity in p–Pb collisions, a similar effect is not present in the kaon-to-pion ratio. The pTdependent structure of such increase is qualitatively similar to those observed in pp and heavy-ion collisions. At high pT(>10GeV/c), the particle ratios are consistent with those reported for pp and Pb–Pb collisions at the LHC energies. At intermediate pTthe (anti)proton RpPbshows a Cronin-like enhancement, while pions and kaons show little or no nuclear modification. At high pTthe charged pion, kaon and (anti)proton RpPbare consistent with unity within statistical and systematic uncertainties.