Heavy Ion physics with the ALICE experiment at the CERN LHC

Abstract

After close to 20 years of preparation, the dedicated heavy ion experiment ALICE took first data at the CERN LHC accelerator with proton collisions at the end of 2009 and with lead nuclei at the end of 2010. After a short introduction into the physics of ultra-relativistic heavy ion collisions, this article recalls the main design choices made for the detector and summarizes the initial operation and performance of ALICE. Physics results from this first year of operation concentrate on characterizing the global properties of typical, average collisions, both in pp and nucleus-nucleus reactions, in the new energy regime of LHC. The pp results differ, to a varying degree, from most QCD inspired phenomenological models and provide the input needed to fine-tune their parameters. First results from Pb-Pb are broadly consistent with expectations based on lower energy data, indicating that high density matter created at LHC, while much hotter and larger, still behaves like a very strongly interacting, almost perfect liquid.

Talk given at Royal Society meeting on "Physics at the high energy frontier - the Large Hadron Collider project", London, 16 - 17 May 2011, to be published in "Philosophical Transactions of the Royal Society A"

References in corpus (10)

• Centrality dependence of the charged-particle multiplicity density at mid-rapidity in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV
• Suppression of charged particle production at large transverse momentum in central Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=2.76$ TeV
• Heavy-Quark Kinetics in the QGP at LHC
• Thermal Dileptons at LHC
• Two-pion Bose-Einstein correlations in central Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 2.76 TeV
• Production of pions, kaons and protons in pp collisions at $\sqrt{s}=900$ GeV with ALICE at the LHC
• Strange particle production in proton-proton collisions at $\sqrt{s}=0.9$ TeV with ALICE at the LHC
• First Results from the ALICE experiment at the LHC
• The Future of High Energy Nuclear Physics in Europe
• Status and initial operation of ALICE

Cited by in corpus (11)

• Production of charged pions, kaons and (anti-)protons in Pb-Pb and inelastic pp collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
• Multiplicity dependence of charged pion, kaon, and (anti)proton production at large transverse momentum in p-Pb collisions at $\sqrt{{\text{s}}_{\mathrm{NN}}}$ = 5.02 TeV
• Measurement of $\Lambda$(1520) production in pp collisions at $\sqrt{s}$ = 7 TeV and p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
• Heavy Ion Physics at the LHC: What's new ? What's next ?
• Multiplicity and rapidity dependence of ${\mathrm{K}}^{\ast }(892{)}^0$ and $\varphi (1020)$ production in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV
• ${\mathrm{K}}^{\ast }(892{)}^0$ and $\varphi (1020)$ production in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 8.16 TeV
• Dependence of related parameters on centrality and mass in a new treatment for transverse momentum spectra in high energy collisions
• Strange particle production in jets and underlying events in pp collisions at $\sqrt{s}=7$ TeV with PYTHIA8 generator
• Study of $⟨p_{\mathrm{T}}⟩$ and its higher moments, and extraction of the speed of sound in Pb-Pb collisions with ALICE
• Inclusive photon production at forward rapidities in pp and p$-$Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV
• Light flavor results in p-Pb collisions with ALICE