Abstract: "High-pt azimuthal di-hadron correlations with identified \ associated hadrons"

One of the most striking results from RHIC is the large baryon/meson ratio at intermediate pt (3-6 GeV/c) in central heavy ion collisions. The observed baryon enhancement may indicate that jet fragmentation is not the dominant particle production mechanism at intermediate pt. Alternatively the large baryon/meson ratio could be due to modification of the jet fragmentation process via interactions with the medium. We present measurements of di-hadron azimuthal correlations, with respect to a high-pt pi0 in the Barrel Electromagnetic Calorimeter (BEMC). The analysis is based on a large sample of events, with > 8 GeV of energy deposited in the BEMC, collected in RHIC Run-7. The associated hadrons are identified by the measured energy loss dE/dx in the TPC. The baryon/meson ratio is studied for central and peripheral collisions on both the near and away side of the di-hadron correlation.