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

TL;DR

This paper reports on the measurement of identified charged-hadron production in proton-proton and lead-lead collisions at the LHC, analyzing particle spectra, yields, and ratios to understand particle production mechanisms across different energies and collision centralities.

Contribution

It provides detailed transverse momentum spectra and particle ratios using advanced identification techniques, comparing results across energies and collision systems to previous data and models.

Findings

Proton-proton yields and ratios vary with collision energy.

Pb-Pb spectra depend on collision centrality.

Results are consistent with or extend previous RHIC data.

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.