Spectra of identified hadrons with the ALICE detector in pp and Pb-Pb collisions at the LHC

Abstract

The measurement of identified charged-hadron production at mid-rapidity ($|y| < 0.5$) performed with the ALICE experiment at the LHC is presented for pp collisions at $\sqrt{s}$ = 900 GeV and 7 TeV and for Pb--Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV. Transverse momentum spectra of $\pi^{\pm}$, K$^{\pm}$, p, $\rm \bar{p}$ and multi-strange baryons are measured over a wide momentum range using the $dE/dx$, the time-of-flight and topological particle-identification techniques. In this report, the particle-identification detectors and techniques, as well as the achieved performance, are shortly reviewed. Proton-proton results on particle production yields, spectral shapes and particle ratios are presented as a function of the collision energy and compared to previous experiments and commonly-used Monte Carlo models. Particle spectra, yields and ratios in Pb--Pb are measured as a function of the collision centrality and the results are compared with published RHIC data in Au--Au collisions at $\sqrt{s_{NN}}$ = 200 GeV and predictions for the LHC.