Particle identification plays a key role in the complete understanding of heavy ions collisions in ALICE at the CERN/LHC. The  High Momentum Particle IDentification (HMPID) system will enhance the PID capability of ALICE beyond the momentum range allowed by  the energy loss measurements (ITS and TPC) and by the TOF. The HMPID detector has been designed to extend the useful range for the identification of p/K and K/p, on a track-by-track basis, up to 3 GeV/c and 5 GeV/c respectively.

It will provide inclusive particle ratios and transverse-momentum spectra in the region relevant for the study of phenomena connected with the pre-equilibrium stage of the nucleus–nucleus collisions.

The low yield of high-momentum particles in Pb–Pb collisions at the LHC energy regime justifies the single-arm geometry of the HMPID covering about 5% of the central barrel phase space.