Speaker
Marek Chojnacki
(University of Copenhagen (DK))
Description
The ALICE detector features multiple particle identification systems including: the Time Projection Chamber (TPC), the Inner Tracking System (ITS), a time-of-flight system (TOF) and a Ring-imaging Cherenkov detector (HMPID).
This combination of detectors along with the excellent tracking capabilities of ALICE provides us with the opportunity to measure the production of pi/K/p over a broad transverse momentum (pT) range, from 100 MeV/c up to 20 GeV/c.
Particle identification at low pT (below 1GeV/c) is performed using the energy loss of particles in the ITS and the TPC. The TOF contributes to the identification for the pT range between 0.5 GeV/c and 3-5 GeV/c (depending on the particle type and the colliding system). For high pT (up to 20 GeV/c), particles are identified with the HMPID or the relativistic rise of the energy loss in the TPC.
In this talk an overview of the ALICE results on the production of pi/K/p in pp collisions at
sqrt(s) = 0.9, 2.76 and 7 TeV, and Pb-Pb collisions at sqrt(s_NN) = 2.76 TeV will be presented. The ALICE results from pp collisions provide constraints for the commonly used event generators and are the baseline for the Pb-Pb measurement. The Pb-Pb results will be compared to statistical models and hydrodynamic calculations at low pT and recombination models at intermediate pT. The high pT region provides constraints on models describing parton
energy loss in the hot and dense medium.
Primary author
Marek Chojnacki
(University of Copenhagen (DK))