The ALICE detector setup consists of a central barrel, which measures hadrons, electrons, and photons, a forward muon spectrometer, and other specialized detectors. The central part covers polar angles from 45°C to 135°C and is embedded in a large solenoid magnet.
ALICE detectors during LHC Run1 and Run-2 (2009 to 2018):
From the inside out, the central barrel contains an Inner Tracking System (ITS), a cylindrical Time-Projection Chamber (TPC), three particle identification arrays of Time-of-Flight (TOF), Ring Imaging Cherenkov (HMPID) and Transition Radiation (TRD) detectors, and two electromagnetic calorimeters (PHOS and EMCal). All detectors except HMPID, PHOS, and EMCal cover the full azimuth. The forward muon arm consists of a complex arrangement of absorbers, a large dipole magnet, and fourteen planes of tracking and triggering chambers. Other detectors include: Forward Multiplicity Detector (FMD), Photon Multiplicity Detector (PMD), T0, V0, Zero Degree Calorimeter (ZDC), and ALICE Cosmic Ray Detector (ACORDE) on top of the L3 magnet to trigger cosmic rays. The FMD, PMD, and ACORDE were decommissioned after Run-2.
ALICE upgrade during LHC Long Shutdown-2 (2019 to 2021):
ALICE went through major upgrades of ITS, TPC and installed a new Muon Forward Tracker (MFT) and a new Fast Interaction Trigger (FIT). New readout electronics were installed in muon spectrometer, TOF, TRD, PHOS, EMCAL, and ZDC.
Now ALICE is ready for Run-3 starting from March 2022.
Details of the different ALICE detectors