Φ-Meson production at forward rapidity in p-Pb collisions at sNN=5.02 TeV and in pp collisions at s=2.76 TeV

The first study of Φ-meson production in p-Pb collisions at forward and backward rapidity, at a nucleon-nucleon centre-of-mass energy √sNN=5.02 TeV, has been performed with the ALICE apparatus at the LHC. The Φ-mesons have been identified in the dimuon decay channel in the transverse momentum (pT) range 1<pT<7 GeV/c, both in the p-going (2.03<y<3.53) and the Pb-going (-4.46<y<-2.96) directions - where y stands for the rapidity in the nucleon-nucleon centre-of-mass - the integrated luminosity amounting to 5.01±0.19 nb-1and 5.81±0.20 nb-1, respectively, for the two data samples. Differential cross sections as a function of transverse momentum and rapidity are presented. The forward-backward ratio for Φ-meson production is measured for 2.96<|y|<3.53, resulting in a ratio ~0.5 with no significant pT dependence within the uncertainties. The pT dependence of the Φ nuclear modification factor RpPb exhibits an enhancement up to a factor 1.6 at pT=3-4 GeV/c in the Pb-going direction. The pT dependence of the Φ-meson cross section in pp collisions at √s=2.76 TeV, which is used to determine a reference for the p-Pb results, is also presented here for 1<pT<5 GeV/c and 2.5<y<4, for a 78±3 nb-1integrated luminosity sample.