Results and Future Plans of ALICE at the LHC

1. Karel Šafařík for the ALICE Collaboration Results and Future Plans ofALICE at the LHC

2. Central Barrel 2 p tracking & PID • Dh ≈± 1 ALICE as of Today ACORDE (cosmics) V0 scintillator centrality |h|:1.7-3.7, 2.8-5.1 T0 (timing) ZDC (centrality) FMD (Nch -3.4<h<5) PMD (Ng, Nch) Muon Spectrometer 2.5 < h < 4 Collaboration: > 1000 Members>100 Institutes > 30 countries Detector: Size: 16 x 26 meters Weight: 10,000 tons

3. TOF TRD TPC ALICE – dedicated heavy-ion experiment at the LHC vertexing HMPID • particle identification (practically all known techniques) • extremely low-mass tracker ~ 10% of X0 • excellent vertexing capability • efficient low-momentum tracking – down to ~ 100 MeV/c ITS

4. LHC had till now two heavy-ion runs • in 2011 – already above nominal instant luminosity! • This year (2012) dedicated to p–Pb run • plan for ~ 30 nb-1 • (but the cross section for rare probes ~ 200 smaller) LHC Heavy-Ion running

5. ALICE Results – Highlights

6. ALICE heavy-ion programme approved for ~ 1 nb-1: • 2013–14 Long Shutdown 1 (LS1) • completion of TRD and CALs • 2015 Pb–Pb at √sNN = 5.1 TeV • 2016–17 (maybe combined in one year) Pb–Pbat √sNN = 5.5 TeV • 2018 Long Shutdown 2 (LS2) • 2019 probably Ar–Ar high-luminosity run • 2020 p–Pb comparison run at full energy • 2021 Pb–Pb run to complete initial ALICE programme • 2022 Long Shutdown 3 (LS3) • this would improve statistical significance of our main results by a factor about 3 • physics reach extended by the new energy and completion of TRD and CALs Order/choice of nuclei may change Approved ALICE programme

7. Precision measurement of the QGP parameters at mb = 0 • to fully exploit scientific potential of the LHC– unique in: • large cross sections for hard probes • high initial temperature • For ALICEthis means: • luminosity upgrade – target 50 kHz minimum bias rate for Pb–Pb • run ALICE at this highrate, inspecting all events • upgrade heavy-ion programme already after LS2 (2018) • collect more than 10 nb-1 of integrated luminosity • implies running with heavy ions few years after LS3 • for core physics programme – factor > 100 increase in statistics • (maximum readout with present ALICE ~ 500 Hz) • for triggered probes increase in statistics by factor > 10 Heavy-Ion Physics @ LHC

8. Main physics topics, at the LHC uniquely accessible with the ALICE detector: • measurement of heavy-flavour transport parameters: • diffusion coefficient – azimuthal anisotropy and RAA • in-medium thermalization and hadronization – meson-baryon • mass dependence of energy loss – RAA • study of QGP properties via transport coefficients (h/s, q) • measurement of low-mass and low-ptdi-leptons • chiral symmetry restoration – vector-meson spectral function • disappearance of vacuum condensate and generation of hadron masses • QGP thermal radiation – low-mass di-lepton continuum • space-time evolution of the QGP – radial and elliptic flow of emitted radiation • J/y , y’, and cc states down to zero pt in wide rapidity range • yields and transverse momentum spectra – RAA, elliptic flow • density dependence – central vs. forward production • statistical hadronization vs. dissociation/recombination ˆ Core physics motivation

9. Jet quenching and fragmentation • jet energy recuperation at very low pt • heavy-flavourtagged jets, gluon vs. quark induced jets • heavy-flavour produced in fragmentation • particle identified fragmentation functions • Heavy-nuclear states • high statistics mass-4 and -5 (anti-)hypernuclei • search for H-dibaryon, Ln bound state, etc. … and more

10. improved vertexing and tracking at low pt • preserve particle-identification capability • high-luminosity operation without dead-time • new, smaller radius, beam pipe • new inner tracker (ITS) (performanceand rate upgrade) • high-rate upgrade for the readout of the TPC, TRD, TOF, CALs, DAQ-HLT, Muon-Arm and Trigger detectors • target for installation and commissioning LS2 (2018) ALICE detector upgrade • additional proposals under considerations to extend the scope of the ALICE upgrade (decision in the fall of this year): • VHMPID – a new high-momentum PID capabilities • MFT – b-tagging for J/ψ, low-mass di-muons • FoCal – low-x physics with identified g/p0

11. New Inner Tracking • seven layers silicon tracker • pointing resolution improved ~ 3 times • very close to the interaction point – innermost layer 22 mm • low material budget – X/X0 ~ 0.3% per layer • substantially improved standalone tracking efficiency • and pt resolution inner barrel new ITS high rate

12. TPC continuous readout without gating grid • minimize ion feedback from amplification region • change MWPC readout to GEM readout • preserving tracking and particle identification capabilities • online calibration and data reduction in HLT • at 50 kHz of Pb–Pbinteraction: reduction factor of ~ 25, event rate tape 25 kHz, throughput to mass storage 20 GB/s TPC upgrade

13. two of the benchmark channels of ALICE upgrade • beauty via non-prompt D0 -> Kp– mass dependence of energy loss • needs precision of the new ITS • Lc– charm in-medium hadronization, baryon–meson ratio • needs both: the new ITS and luminosity ~ 10 nb-1 B/D RAA suppression Lc/D enhancement Pb–Pb 1010 central events New ITS Example: Heavy-flavourproduction Pb–Pb 109 central events New ITS

14. Thermalization of heavy quarks High rate, new ITS No high rate, new ITS ˆ Example: Heavy-flavourv2 • need >> 1 nb-1for precise measurement of charm and beauty v2 • systematic uncertainties and corrections mostly cancel in v2 • Other key measurements: Lb, Xc, B decays, virtual g, y’, cc, tagged jets…

15. ALICE measurements

16. ALICE is obtaining a wealth of physics results from the two first LHC heavy-ion runs • before LS2 (2018): p–Pb and Pb–Pb, higher energy and complete approved ALICE detector • To fully exploit the LHC potential with ALICE : • new inner tracking system – 3 times better vertexing • high-rate capability – x100 statistics • implementing upgrade during LS2 (2018) • integrated luminosity >10 nb-1 – running beyond LS3 (2022) Conclusions