Production of Charged Pions, Kaons, and Protons at high pT in Pb-Pb
collisions measured with ALICE at the LHC
Dr. Antonio Ortiz
Universidad de Lund, Suecia
The main tracking detector in the central barrel ($|\eta|<1$) of the ALICE
experiment is the Time Projection Chamber. In addition to charged particle
tracking it provides particle identification (PID) through the measurement
of the specific energy loss, $dE/dx$. At low momentum ($p < 1$ GeV/c),
pions, kaons, and protons can be cleanly separated. Thanks to the
relativistic rise of the $dE/dx$, the relative yield of pions, kaons, and
protons can also be extracted statistically at higher momenta, $p > 3$
GeV/c. In this talk, spectra for charged pions, kaons, and protons from pp
collisions at $\sqrt{s} = 2.76$ TeV and Pb-Pb collisions at $\sqrt{s_{NN}}$
= 2.76 TeV will be presented, and the nuclear modification factor $R_{AA}$
will be derived. The evolution of $R_{AA}$ with collision centrality and
transverse momentum will be discussed, and compared to unidentified charged
particles, $K_{s}^{0}$ , $\Lambda$, and theoretical predictions.