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Future of Heavy Ions@LHC. SPS/RHIC programs Initial LHC Program 2008 - ~ 2017 Long Term Options > 2017. History. AGS (1986 - 1998) Beam : E lab < 15 GeV/N, Ö s ~ 4 GeV/N Users : 400 Experiments : 4 big , several small SPS (1986 - 2003)
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Future of Heavy Ions@LHC SPS/RHIC programs Initial LHC Program 2008 - ~ 2017 Long Term Options > 2017 HI@LHC J. Schukraft
History • AGS (1986 - 1998) • Beam: Elab < 15 GeV/N, Ös ~ 4 GeV/N • Users: 400 Experiments: 4 big, several small • SPS (1986 - 2003) • Light Ions(O, S) : 1986 – 1992 Heavy Ions (In, Pb): 1994 - 2003 • Beam: Elab =40, 80, 160, 200 GeV/N, Ös < 20 GeV/N • Users: 600 Experiments: 6-7 big, several small, 3 ‘generations’ • RHIC I (2001 – 2012 ?) • Beam: Ös < 200 GeV/N • Users: 1000 • Experiments: 2 big, 2 small
Summary of RHIC Runs 1-5 Delivered Luminosity (Physics Weeks) 3 runs Au-Au 1 run d-Au 1 run Cu-Cu Energies: 22, 62, 130, 200 GeV Quark Matter 2005, Budapest 3 2006: pp (spin) physics
RHIC – a Uniquely Flexible High Luminosity Collider (Nucleon-pair luminosity A1A2L allows comparison of different species) RHICnucleon-pair luminosity delivered to PHENIX Luminosity increased by 2 orders of magnitude in 4 years. Luminosity increased by 2 orders of magnitude in 4 years. Quark Matter 2005, Budapest 4
Near and mid term: 2006-2012 Strawman schedule: depends on funding (TBD)* EBIS construction RHIC II: construction operation RHIC Accelerator & Detector R&D TOF and VTX construction; Muon trigger + “Small” upgrades: HBD, FMS, DAQ STAR HFT & PHENIX FVTX Next Generation Detector Upgrades STAR Forward/Inner Tracker System PHENIX Inner Tracker and Nosecone Cal Other approaches? Machine improvements, modest L upgrade Many detector upgrades R&D for RHIC II (eRHIC) LHC Heavy Ion Program Quark Matter 2005, Budapest 5
RHIC Upgrade: overview A. Drees X upgrade critical for success O upgrade significantly enhances program Quark Matter 2005, Budapest 6
Long term: 2013-2020 • eRHIC • Added e+A and polarized e+p capabilities • New detector, augmented user community • A+A, p+A, polarized p+p still available • Construction possible 2012-2014 RHIC II Luminosity ~ 10 x current L (40 x design L) Quark Matter 2005, Budapest 7
ALICE Baseline program • expect ~ 10 year ‘baseline’ program 2008 – 2017 • pp: after few years diminishing return in terms of running time <-> statistics • HI: 3 D phase space to cover: statistics – beam type – beam energy • first 5 years • initial Pb-Pb run in 2008 (1/20th design L, i.e. ~ 5 x 1025 ) • 2 Pb-Pb runs (medium -> design Luminosity L ~ 1027), integrate ~ 1nb-1 • 1 p A run (measure cold nuclear matter effects, e.g. shadowing) • 1 low mass ion run (energy density & volume dependence) • continuous running with pp (comparison data, some genuine pp physics) • following ~ 5 years • program and priorities to be decided based on results • lower energies (energy dependence, thresholds, RHIC, pp at 5.5 TeV) • additional AA & pA combinations • increased statistics • expect modest detector modifications & upgrades • discussion has started, R&D to follow after 2007, decisions ~ 2009
ALICE on the medium term • finish baseline detector by ~ 2010 • PHOS and TRD have ‘late funding’, expected to be complete by 2009/2010 • new jet calorimeter (very important for jet-quenching) • US project, approved by DOE (CD-1 level) and LHCC • to be installed by 2010 (very aggressive schedule) • Other ideas for > 2010 • PID for pt 5 – 20 GeV (based on RHIC results) • 2nd generation vertex detector (smaller beampipe) -> improve heavy quark physics • detectors for forward physics (low-x on pA and AA) • improved DAQ & HLT (more sophisticated and selective triggers) • increased rate capability of TPC (faster gas, increased R/O speed) • ALICE pp running • expect to collect the needed pp statistics early (order 5 years ?) • exceptions: • setting-up period prior to HI running (order few weeks every year) • some comparison data with new detectors (several weeks spread over several years ??)
Long Term Prospects • Impossible to predict before first LHC results … • Possible directions • increased energy:Unlikely • need at least factor of 10; energy density e ~ ln (√s) • currently no physics justification ( e sufficient, hard probes abundant at LHC) • however, I may be wrong… • increased luminosity: Quite likely • some signals at LHC severely statistics limited (eg Y production, g-jets correlations) • factor 4-5 may be possible, but by no means trivial • factor > 10 very challenging & expensive (eg electron cooling ?) • better detector • as the physics requires…. • change of direction • electron-nucleus scattering (eRHIC, eLHC?), high nuclear density (FAIR), .. ???
HI Luminosity increase • LHC Pb design Lumi • design L = 1027 cm-2 s-1, <L> ~ 0.3 – 0.5 Lmax (depends also on # expts) • ALICE assumption: integrated L/year(106s) ~ 0.5 nb-1 • design L close to several LHC limitations => could be optimistic !!! • Examples for statistics limited Signals • Y suppressions: • order 7000 Y, 1000 Y’’ per standard year in ALICE • NA60: order 105 or more J/Psi !!! • g-jet correlations (‘golden channel’ to study jet quenching) • order 1000 g-jet events/year with pt > 30 GeV • need order 104 for fragmentation functions at high z (most sensitive to quenching) • Detector modifications to benefit from increase L • current limitation is TPC (pile-up, possibly space charge) • TPC designed for up to dNch/dy = 8000, expectation is more like 2000 – 4000 • significant rate increase possible (faster gas, accept pile-up for high pt physics) • muon spectrometer needs no modifications 3 – 4 years running at 4-5 x design L would give the needed order of magnitude increase in statistics !!
Quarkonia -> mm B -> J/Y + X Normalization on open b Statistics for 0.5 nb-1 • J/Y: excellent • Y’: marginal • Y: ok (7000) • Y’: low (2000) • Y’’: very low (1000)
J/Psi statistics ~ 30 k for NA60 J/Psi statistics ~ few 1000 for PHENIX Quarkonia Suppression • New results indicate that J/Psi may not be suppressed at RHIC (or SPS) • Y may not melt even at LHC ! • J/Psi, Y’ and Y’’ are more important than anticipated => need for more Luminosity • > 104 Y’ (Y’’) would require > 5(10) years at 0.5nb-1/year at LHC
Summary • ALICE Baseline program 2008 to at least 2017 • emphasis will be on Pb-Pb at highest energy to collect ~ 1-2 nb-1 (>3 high L runs ?) • we need at least 10 years to collect sufficient statistics and investigate a minimum of different AA and pA combinations, at least two different energies (incl pp at 5.5 TeV) • we need to run about 5 full years with pp at 14 TeV • we need few weeks/year pp running after that • we expect to have some smaller detector upgrades > 2010 • LHC Luminosity upgrade to order 5x1027 cm-2s-1 • factor 5 to 10 above ‘baseline’, depending on ‘current LHC’ limitations • could come as early as possible (eg together with ‘super LHC’) • significant physics benefits for hard probes • ALICE detector should be able to run with some ‘modest’ upgrades