Transcript Need for pA collisions at LHC

Future of Heavy Ions@LHC
 SPS/RHIC programs
 Initial LHC Program
 2008 - ~ 2017
 Long Term Options
 > 2017
11 Nov 2005
HI@LHC J. Schukraft
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History
 AGS
 Beam:
 Users:
 SPS
(1986 - 1998)
Elab < 15 GeV/N, s ~ 4 GeV/N
400
Experiments: 4 big, several small
(1986 - 2003)
 Light Ions(O, S) : 1986 – 1992 Heavy Ions (In, Pb): 1994 - 2003
 Beam:
Elab =40, 80, 160, 200 GeV/N, s < 20 GeV/N
 Users:
600
Experiments:
6-7 big, several small, 3 ‘generations’
 RHIC I
(2001 – 2012 ?)
 Beam:
s < 200 GeV/N
 Users:
1000
 Experiments:
2 big, 2 small
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11/11/2005 HI@LHC J. Schukraft
Summary of RHIC Runs 1-5
Delivered Luminosity (Physics Weeks)
Year
2001
Run Plan
Au-Au at 130 GeV/A
Sample
20 b-1 (6 wks)
2001 –
2002
Au-Au at 200 GeV/A
Comm./run pp at 200 GeV
Au-Au at inj. E: 19 GeV/A
260 b-1 (16wks) Global properties; particle spectra; first look at
hard scattering.
-1
1.4 pb (5 wks) Comparison data and first spin run
Global connection to SPS energy range
0.4 b-1 (1 day)
d-Au at 200 GeV/A
74 nb-1 (10wks)
pp at 200 GeV
5 pb-1 (6 wks)
2004
Au-Au at 200 GeV/A
Au-Au at 62 GeV/A
pp at 200 GeV
3740 b-1(12wks) “Long Run” for high statistics, rare events
67 b-1 (3wks) Energy Scan
Spin Development: Commission jet target
100 pb-1 (7wks)
First measurements with longitudinal spin pol.
2005
Cu-Cu at 200 GeV/A
Cu-Cu at 62 GeV/A
Cu-Cu at 22 GeV/A
pp at 200 GeV
pp at 410 GeV
42 nb-1 8wks
1.5 nb-1 12 days
18 b-1 39 hrs
30 pb-1 10 wks
0.1 pb-1 1 day
2003
2006: pp (spin) physics
Physics
First look at RHIC collisions
Comparison data for Au-Au analysis; low-x
physics in cold nuclear matter
Spin Development & Comparison data
Comparison studies: surface/volume & impact
parameter effects; Energy Scan
Spin Development:
Lum., Polarization
3 runs Au-Au
First long data run for spin
1 run d-Au
Quark Matter 2005, Budapest 1 run Cu-Cu
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Energies: 22, 62, Brookhaven
130, 200
GeV
Science Associates
RHIC – a Uniquely Flexible High Luminosity Collider
(Nucleon-pair luminosity A1A2L allows comparison of different species)
RHIC nucleon-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
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Brookhaven Science Associates
Near and mid term: 2006-2012
Strawman schedule: depends on funding (TBD)*
FY 2006
FY 2007
FY 2008
FY 2009
FY 2010
FY 2011
FY 2012
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
Machine improvements, modest L upgrade
Many detector upgrades
R&D for RHIC II (eRHIC)
Next Generation Detector Upgrades
STAR Forward/Inner Tracker System
PHENIX Inner Tracker and Nosecone Cal
Other approaches?
LHC Heavy Ion Program
Quark Matter 2005, Budapest
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Brookhaven Science Associates
RHIC Upgrade: overview
Upgrades
High T QCD…. QGP
e+e-
PHENIX
Hadron blind detector
Vertex Tracker
Muon Trigger
Forward cal. (NCC)
X
X
heavy
flavor
X
jet
tomog.
O
O
Spin
quarkonia
O
O
O
W
Low-x
ΔG/G
X
X
O
O
X
STAR
Time of Flight (TOF)
MicroVtx (HFT)
Forward Tracker
Forward Cal (FMS)
DAQ 1000
RHIC Luminosity
O
X
O
O
X
O
X
X
O
X
X
O
O
O
O
O
X
X
O
O
X upgrade critical for success
Matter 2005, Budapest
O upgradeQuark
significantly
enhances program
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X
O
O
A. Drees
Brookhaven Science Associates
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
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Brookhaven Science Associates
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

8 discussion has started, R&D to follow after 2007, decisions ~ 2009
11/11/2005 HI@LHC J. Schukraft
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 ??)
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11/11/2005 HI@LHC J. Schukraft
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), .. ???
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11/11/2005 HI@LHC J. Schukraft
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)
3 – 4 years running at 4-5 x design L would give the needed
order of magnitude increase in statistics !!
 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)
11muon spectrometer needs no modifications
11/11/2005 HI@LHC J. Schukraft
Quarkonia -> 
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)
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6/2006 Los Alamos J. Schukraft
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
J/Psi statistics ~ 30 k for NA60
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J/Psi statistics ~ few 1000 for PHENIX
11/11/2005 HI@LHC J. Schukraft
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
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11/11/2005 HI@LHC J. Schukraft