Particle-Yield Modification in Jetlike Azimuthal Dihadron Correlations in Pb-Pb Collisions at √sNN=2.76  TeV

The yield of charged particles associated with high-pt trigger particles (8<pt<15  GeV/c) is measured with the ALICE detector in Pb-Pb collisions at √sNN=2.76  TeV relative to proton-proton collisions at the same energy. The conditional per-trigger yields are extracted from the narrow jetlike correlation peaks in azimuthal dihadron correlations. In the 5% most central collisions, we observe that the yield of associated charged particles with transverse momenta pt>3  GeV/c on the away side drops to about 60% of that observed in pp collisions, while on the near side a moderate enhancement of 20%–30% is found.