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.