Transcript Heavy Ions @ LHC  Heavy Ion Physics Heavy Ion Physics at LHC

Heavy Ions @ LHC
 Heavy Ion Physics
 (in VERY general terms)
Heavy Ion Physics at LHC
 ALICE
 Collaboration
 Detector
 Performance
Geneva June 2004
HI@LHC J. Schukraft
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Pretty Messy …
2
NA35 streamer chamber picture, ca 1990
Geneva 2004 J. Schukraft
The QCD Phase transition
 QGP = true ground state of QCD
 melting matter => deconfinement
 melting vaccum (gluon condensate)
=>chiral symmetry restoration
 dynamical origin of constituent mass
 Phase transitions involving
elementary quantum fields
 phase transitions and spontaneous
symmetry breaking central to HEP
 QCD transition is the only one
accessible dynamically
 Cosmology & Astrophysics
 early Universe at ~ 1 ms
 interior of neutron stars
 new domain of hot & dense QCD
 surprises ?
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Melting Matter
4
 Deconfinement in QGP
 long range QCD potential
screened by high parton density
 partons move freely over long
distance
‘colour conductor’
 no bound states possible
‘resonance melting’
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The Dark Mystery of Matter
What stuff is the Universe made of ??
 Elementary Particles
0.1%
 12 matter particles (quarks, leptons)
 only 4 relevant today (u, d, e, n)
 13 force particles (3 massive, 10 massless)
 Composite Particles (hadrons)
4%
 Dark Matter
 made of unknown particles
 Dark Energy
73%
 vacuum energy
 of completely unknown origin
 should be infinite or exactly 0
 hundreds…
 only 2 are relevant (p,n), making nuclei
 luminous normal matter (stars, galaxies) 0.05%
 dark normal matter (gas, planets, ..)
3.95%
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23%
We don’t know how and why for ~ 5%
We don’t even know what for the other 95%
 EW Higgs mechanism
 symmetry breaking => Higgs VeV
 H coupling to particles => ‘true’ mass
for ‘elementary’ particles u,d,s,c,t,b,W,Z, ….
 QCD ‘Higgs’ mechanism
 chiral symmetry breaking
 gluon condensate
<0|gg|0> ~ 200 MeV/fm3
 coupling to partons => ‘effective’ mass
for hadrons (p,K,p,n,….)
Quark condensate <YY> in lattice QCD
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Lattice QCD Results
 recent progress
Tc ~ 175 ± 8 ± 8 MeV  improved actions
 improved symmetries
 larger lattices
 crit. temperature
 energy density
 EOS
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ec ~ (6±2) Tc4
(e-3P) 0
Heavy Ion Collision
t = - 3 fm/c
t =0
hard collisions
t = 10 fm/c
t = 1 fm/c
pre-equilibrium
t = 40 fm/c
hadron gas
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freeze-out
t = 5 fm/c
QGP
?
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11
Jet
Quenching
Soft Probes: Elliptic Flow
 Flow: Correlation between coordinate and momentum space
SCIENCE Vol: 298
 close particles move at similar velocity and direction
2179 (2002) 7Li
 flow builds up in an interacting medium with pressure gradients
 for given boundary conditions, flow profile depends on
 Equation of State EoS and viscosity h of ‘fluid’
 Hydrodynamics of perfect fluid: h= 0, l= 0 (‘strongly interacting’)
Dpx > Dpy
Elliptic Flow reduces spatial
anisotropy -> acts at early times
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Geneva 2004 J. Schukraft
Flow at RHIC
Momentum space

d 3N
1 d 2N 

E 3 
1

2
v
cos
n


Y




 n
r

d p 2p pt dpt dy  n 1

v2  cos 2(  Y r ) ,   tan (
1
py
px
)
STAR PRL 86, (2001)
402
|h| < 1.3
0.1 < pt < 2.0
 matter at RHIC: ~ perfect fluid with ~ zero mean free path !
 huge effect (almost 2:1 at high pt)
 almost perfect agreement with hydro f(impact parameter, pt, particle mass)
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Geneva 2004 J. Schukraft
Closing in on the EoS
 Good agreement with Lattice EoS
 agreement with hydro at RHIC (coincidence ? => LHC !)
 quantitative analysis (incl systematic errors) in progress
 Hydro = zero mfp => fluid, gas ! (sQGP, s >> few mb)
 almost ideal fluid, h/s ~ 0.1 (much better than water !)
 h/s = 1/4p from N=4 conformal susy FT
in the strong coupling limit
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Geneva 2004 J. Schukraft
Hard Probes : Jet Quenching
Vacuum
beams of
hard probes:
jets, J/y ….
leading
particle NOT
suppressed
hadrons
q
QGP
q
hadrons
leading
particle NOT
suppressed
peripheral
central
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 high pt partons:
jet quenching measures
‘radiation ‘ length of QGP
dE ~ mD2 x L2
mD = Debye screening mass
 Vacuum: fragment into hadrons => JETS
 Matter: additional scattering => more gluon radiation
 normal ‘cold’ matter: small effect
 QGP: strong effect (up to several 10 GeV)
 observables of ‘jet quenching’
 leading parton looses energy
 energy shows up in soft partons around jet axis
Geneva 2004 J. Schukraft
Experimental Facilities
 AGS
 Beam:
 Users:
 SPS
 Beam:
 Users:
 RHIC
(1986 - 1998)
Elab < 15 GeV/N, s ~ 4 GeV/N
400
Experiments: 4 big, several small
X5
(1986 - 2003)
Elab < 200 GeV/N, s < 20 GeV/N
600
Experiments:
6-7 big, several small
X 10
(>2000)
 Beam:
s < 200 GeV/N
 Users:
1000
 Experiments:
2 big, 2 small
X 30
 LHC
(>2007)
 Beam:
s < 5500 GeV/N
 Users:
1000
 Experiments:
1 dedicated HI, 3 pp expts
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Geneva 2004 J. Schukraft
NA44
NA49
ls 
2 ss
uu  dd
factor ~2
SPS Experiments
‘Nucleo-synthesis’
‘Hubble Flow’
NA49/Ceres
mass generation
Deconfinement
NA50
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Current hunting ground for
Quark Gluon Plasma
The Relativistic Heavy Ion Collider
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RHIC Experiments
4 Experiments,
~ 1000 people from ~ 100 Institutes
in ~ 20 Countries
 STAR
 ~ 400 people, ~ 33 Institutes
 hadronic probes
 particle spectra/ratios, HBT, jets
 large acceptance TPC, solenoid
 BRAHMS
 ~ 70 people, ~ 12 Institutes
 single inclusive hadrons
 central and forward region
19  2 spectrometer arms (tracking+PID)
 PHENIX
 ~ 500 people, ~ 50 Institutes
 e.m. probes
 e,m,g,small area hadrons
 several special purpose spectrometer arms
 PHOBOS
 ~ 50 people, ~ 14 Institutes
 very low pt hadrons
 down to ~ 20 MeV
 Silicon telescope + TOF array
Geneva 2004 J. Schukraft
STAR
parton energy loss
RHIC Experiments
Jet Quenching
PHENIX
BRAHMS
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small angle particles
PHOBOS
Particle Production
Geneva 2004 J. Schukraft
Future place for studying the
Quark Gluon Plasma
The Large Hadron Collider
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Physics at LHC
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Heavy Ions in LHC
 energy


Ebeam = 7 x Z/A
s = 5.5 TeV/A (Pb-Pb),
[TeV]
14 TeV (pp)
 beams
 possible combinations: pp, pA, AA
 constant magnetic rigidity/beam ('single magnet')
 expected heavy ion running
 ~ 6 weeks heavy ion runs, typically after pp running (like at SPS)
 initial emphasis on Pb-Pb
 pp and pA comparison runs
 intermediate mass ion (eg Ar-Ar) to vary energy density
 later options: different ion species, lower energy AA and pp
 luminosity
 low L runs:
L [cm-2s-1]
 avoid pile-up in TPC
 high L runs:
Rate [kHz]
 max rate in muon arm
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Pb-Pb
Ar-Ar
pp
1027
3x1027 to 1029
1029 to 3x1030
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8 to 250
7 to 200
Geneva 2004 J. Schukraft
H.I. Physics@LHC: Caveat
BIG Step ahead: SPS
x 12
RHIC
x 28 LHC
 long distance QCD is difficult to predict
Predictions are notoriously difficult,
in particular if they concern the future..
 Theory well known, not so its consequences or manifestation
 HEP@LHC: Theory unknown, but each candidate makes precise predictions
 the fate of 'expectations' at SPS and RHIC
 some expectations turned out right:
 SPS: strangeness enhancement
 some turned out wrong:
 SPS: large E-by-E fluctuations
 a number of unexpected surprises:
 SPS: J/Psi suppression
RHIC: particle ratios, jet-quenching
RHIC: multiplicity dN/dy
RHIC: elliptic flow, 'HBT-puzzle'
 lesson when preparing ALICE at LHC
 guided by theory and expectations, but stay open minded !
 'conventional wisdom'
 soft physics: smooth extrapolation of SPS/RHIC
 hard physics: new domain at LHC
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necessary, but boring ???
Geneva 2004 J. Schukraft
Hard Processes at the LHC
 Main novelty of the LHC: large hard cross section
s
hard
/s
tot
~2% at SPS
~50% at RHIC
~98% at LHC
X 2000
 Hard processes are extremely useful tools
 happen at t = 0 (initial stage of the collision)
 have large virtuality Q and small “formation time” Dt  1/Q
 probe matter at very early times (QGP) !!!
hard processes can be calculated by pQCD  predicted
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Jets in ALICE |h|<0.9
 ideal energy for jet-quenching:
around 100 GeV
 pQCD applicable
 jets measurable above soft background
 energy loss still relatively large effect
 DE/E ~ O(10%), decreasing with E !
pp
L = 1030cm-2s-1
Pb Pb rates:
Reasonable
rate up to ET
~300 GeV
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pt jet >
(GeV/c)
jets/event
accepted
jets/month
5
3.5 102
4.9 1010
50
7.7 10-2
1.5 107
100
3.5 10-3
8.1 105
150
4.8 10-4
1.2 105
200
1.1 10-4
2.8 104
Geneva 2004 J. Schukraft
Heavy Quarks & Quarkonia
 copious heavy quark production
 charm @ LHC ~ strange @ SPS
 hard production => 'tracer' of
QGP dynamics (statistical hardonization ?)
 2 mc ~ saturation scale => change in production ?
 jet-quenching with heavy quarks visible in inclusive spectra ?
RHIC
LHC
 Y ds/dy LHC ~ 20 x RHIC
 Y will probably need
higher Lumi at RHIC
 even at LHC Y'' is difficult
Y production
R. Vogt, hep-ph/0205330
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Initial Conditions
 my pre-RHIC guess (QM2001)
 still expect conditions to be significantly different
 only LHC will give the final answer on dn/dy!
Central collisions
Significant gain in e, V, t
x 10 SPS -> LHC
x 3-5 RHIC -> LHC
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SPS
RHIC
LHC
s1/2(GeV)
17
200
5500
dNch/dy
430
700-1500
2-8 x103
e (GeV/fm3)t0=1fm
2.5
3.5-7.5
15-40
Vf(fm3)
103
(?)7x103
2x104
tQGP (fm/c)
<1
1.5-4.0
4-10
t0 (fm/c)
~1
~0.5
<0.2
Geneva 2004 J. Schukraft
The Soft Stuff
 changes in expansion dynamics & freeze-out ARE expected
 will the measured transverse HBT volume (finally) increase ?
 thermal freeze-out temperature ?
 how will charm fit into particle ratios ?
AGS
 will anisotropic flow stay on hydro prediction ?
 Event-by-Event fluctuations ?
 measurement accuracy increases ~ #particles
RHIC
LHC ?
Freeze-out Hyper surface
SPS
Biggest surprise
would be none..
LHC
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ALICE Collaboration
CROATIA
MEXICO
CHINA
ARMENIA
USA
UKRAINE
INDIA
~ 1000 Members
(63% from CERN MS)
~30
Countries
~80
Institutes
ROMANIA
S. KOREA
ITALY
JINR
FRANCE
RUSSIA
SWITZERLAND
FINLAND
DENMARK
GREECE
NETHERLANDS
UK
PORTUGAL
SWEDEN
CERN
NORWAY
GERMANY
SLOVAKIA
POLAND
CZECH REP.
HUNGARY
1200
1000
ALICE
Collaboration statistics
TRD
800
MoU
600
TP
400
200
0
1990
30
LoI
1992
1994
1996
1998
2000
2002
2004
Geneva 2004 J. Schukraft
ALICE Design Philosophy
 General Purpose Heavy Ion Detector
 one single dedicated HI expt at LHC
 ATLAS/CMS will contribute, but priority is pp physics
 AGS/SPS: several (6-8) 'special purpose expts'
 RHIC: 2 large multipurpose + 2 small special purpose expts
 cover essentially all known observables of interest
 comprehensive study of hadrons at midrapidity
 large acceptance, excellent tracking and PID
 state-of-the-art measurement of direct photons
 excellent resolution & granularity EM calo (small but performing !)
 dedicated & complementary systems for di-electrons and di-muons
 cover the complete spectrum: from soft (10's of MeV) to hard (100's of GeV)
 stay open for changes & surprises
 high throughput DAQ system + powerful online intelligence ('PC farm‘, HLT)
 flexible & scalable: minimum design prejudice on what will be most interesting
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TOF
HMPID
TRD
TPC
PMD
ITS
Muon Arm
PHOS
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ALICE Set-up
Geneva 2004 J. Schukraft
Central tracking system
•
•
•
•
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ITS
TPC
TRD
TOF
Geneva 2004 J. Schukraft
MUON Spectrometer:
dipole
filter wall
absorbers
trigger chambers
tracking stations
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Forward detectors:
• FMD, T0, V0, ZDC
• PMD
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Specialized detectors:
Cosmic rays trigger
• HMPID (RICH)
• PHOS High Resolution EM Calorimeter
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ALICE Acceptance
 central barrel -0.9 < h < 0.9
 tracking, PID
 single arm RICH (HMPID)
 single arm em. calo (PHOS)
-6
 forward muon arm 2.4 < h < 4
 multiplicity -5.4 < h < 3
 including photon counting in PMD
 trigger & timing dets
 Zero Degree Calorimeters
 T0: ring of quartz window PMT's
 V0: ring of scint. Paddles
-4
FMD -5.4 < h < -1.6
-3
PMD -2.3 < h < -3.5
-1
0
ITS+TPC+TRD+TOF:
-0.9 < h < 0.9
1
ITS multiplicity -2 < h < 2
2
FMD 1.6 < h < 3
3
Muon arm 2.4 < h < 4
4
Azimuth
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HMPID
-.45 < h < 0.45
D
-2
Rapidity
 absorber, dipole magnet
tracking & trigger chambers
PHOS
-.12 < h < 0.12
D
90o
180o
270o
360o
Geneva 2004 J. Schukraft
 still largest magnet
 magnet volume: 12 m long, 12 m high
 0.5 T solenoidal field
The ALICE
Magnet:
ready for the experiment to move in!
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Geneva 2004 J. Schukraft
ALICE R&D
1990-1996:Strong, well organized, well funded R&D activity
 Inner Tracking System (ITS)
 Silicon Pixels (RD19)
 Silicon Drift (INFN/SDI)
 Silicon Strips (double sided)

 low mass, high density interconnects
 low mass support/cooling

 TPC
 gas mixtures (RD32)
 new r/o plane structures

 advanced digital electronics
V
 low mass field cage
 em calorimeter

 new scint. crystals (RD18)
40
 PID
 Pestov Spark counters V
 Parallel Plate Chambers
V
 Multigap RPC's (LAA)
 low cost PM's
V
 solid photocathode RICH (RD26)
 DAQ & Computing
 scalable architectures with COTS
 high perf. storage media
?
 GRID computing
?
?
 misc
 micro-channel plates V
 rad hard quartz fiber calo.
 VLSI electronics

• R&D made effective use of long (frustrating) wait for LHC
• was vital for all LHC experiments to meet LHC challenge !

Geneva 2004 J. Schukraft
Time of Flight Detectors
 aim: state-of-the-art TOF at ~1/10 current price !
 requirements: area > 150 m2, channels ~ 150,000, resolution s < 100 ps
 existing solution: scintillator + PM, cost > 120 MSF !
 R&D on cheaper fast PM's in Russia failed to deliver
 gas TOF counters + VLSI FEE
 Pestov Spark Counter (PSC)
100 mm gap, > 5 kV HV, 12 bar, sophisticated gas
 s < 50 ps, some 'tails' (?), but only (!) ~ 1/5 cost
 technology & materials VERY challenging

 Parallel Plate Chamber (PPC)
 1.2 mm gap, 1 bar, simple gas & materials
1/10 cost, but only s = 250 ps
 unstable operation, small signal

 Multigap Resistive Plate Chambers (MRPC)
 breakthrough end 1998 after > 5 years of R&D !
many small gaps (10x250 mm), 1 bar, simple gas & materials
 ~ 1/10 cost, s < 100 ps , simple construction & operation,..

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Geneva 2004 J. Schukraft
Time Of Flight
DOUBLE STACK OF 0.5 mm GLASS
cathode pick up pad
Edge of active area
5 gaps
Resistive layer (cathode)
Resistive layer (anode)
160 m2, 160 k channels
r = 3.7 m, s < 100 ps
anode pick up pad
5 gaps
Resistive layer (anode)
Resistive layer (cathode)
cathode pick up pad
Multigap Resistive Plate Chambers
for p, K, p PID
p, K <2 GeV/c; p <4GeV/c
96 readout
pads per
strip
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Inner Tracking System (ITS)
SSD
SDD
SPD
Lout=97.6 cm
 6 Layers, three technologies (keep occupancy ~constant ~2% for max mult)
Rout=43.6 cm
 Silicon Pixels (0.2 m2, 9.8 Mchannels)
 Silicon Drift (1.3 m2, 133 kchannels)
 Double-sided Strip (4.9 m2, 2.6 Mchannels)
43
Material Budget: < 1% X0 per layer !
Major
technological
challenge!
Geneva 2004 J. Schukraft
(all full-custom designs in rad. tol., 0.25 mm process)
Analogue
memory
ADC
ALICE SDD FEE
Pascal chip:
64 channel preamp+ 256-deep
analogue memory+ ADC
Ambra chip:
64 channel
derandomizer
chip
s
ALICE SSD FEE
HAL25 chip:
128 channels
Preamp+s/h+
serial out
Preamplifiers
ALICE PIXEL CHIP
50 µm x 425 µm pixels
8192 cells
Area: 12.8 x 13.6 mm2
13 million transistors
~100 µW/channel
ITS Electronics Developments
And extreme lightweight interconnection techniques:
SSD tab-bondable
Al hybrids
44
Strip module
assembly
Pixel ladder
Drift cooling system
45
System testing and setting up of series production
ITS Support Acceptance Test
Deformation < 200 mm under load of 1 kg
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Tracking Challenge
ALICE 'worst case' scenario:
dN/dych = 8000
NA49
STAR
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TPC
 largest ever
 88 m3, 570 k channels
drift gas
90% Ne - 10%CO2
Central Electrode Prototype
25 µm aluminized Mylar on Al frame
Field Cage
48 diameter
~3m
Inner Vessel
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TPC Field Cage
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50
TPC R/O chambers
 production finished in
Bratislava and GSI
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Photon Spectrometer
for photons, neutral mesons
and g-jet tagging
 single arm em calorimeter
PbW04: Very dense: X0 < 0.9 cm
Good energy resolution (after 6 years R&D):
stochastic 2.7%/E1/2
noise
2.5%/E
constant 1.3%
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 dense, high granularity crystals
 novel material: PbW04
 ~ 18 k channels, ~ 8 m2
 cooled to -25o
PbW04 crystal
Geneva 2004 J. Schukraft
Dimuon Spectrometer
 Study the production of the J/Y, Y', U, U' and
U'’ decaying in 2 muons, 2.4 <h < 4
 Resolution of 70 MeV at the J/Y and 100 MeV
at the U
RPC Trigger Chambers
5 stations of high
granularity
pad tracking chambers,
over 800k channels
Complex absorber/small
angle shield system to
minimize background
(9053cm from vertex)
Dipole Magnet: bending power 3Tm
Geneva 2004 J. Schukraft
Muon Chambers
Station 3-4: Slats
Station 1&2: Quadrants
Trigger RPC
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Muon Magnet
 Dipole Magnet
 0.7 T and 3 Tm
 4 MW power, 800 tons
 World’s largest warm dipole
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Computing Phase Transition
The Problem:
 Online: storing up to 1.2 Gbyte/s
 whole WWW in few hours on tape !
 ~ 10 x RHIC !
 Offline: 18 MegaSI2000
 100,000 PC's in 2000 (500 Mhz)
 ~ 100 x RHIC !!
The Answer:
cheap mass market components
Industry & Moore's law
The Challenge:
ALICE DC III
make 100,000 mice do the
work of one elephant
new computing paradigm:
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The GRID
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Data Challenges
reduced number of components (PC’s etc.) available in 2003
reliability of new equipment imperfect
MByte/s
3000
DAQ bw
2500
DAQ bw ALICE traffic
DAQ bw flat traffic
2000
MByte/s
800
1500
700
M.S. bw milestone
600
M.S. bw achieved
1000
500
500
400
0
1998 1999 2000 2001 2002 2003 2004 2005 2006
300
200
100
0
1998 1999 2000 2001 2002 2003 2004 2005 2006
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ALICE GRID is there: ALIEN
OSU/OSC
LBL/NERSC
Dubna
Birmingham
NIKHEF
Saclay
GSI
CERN
Merida
Padova
IRB
Bologna
Lyon
Torino
Bari
Cagliari
Yerevan
Catania
Kolkata, India
Capetown, ZA
 The CORE GRID functionality exists
 Distributed production working, distributed analysis to be done...
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Geneva 2004 J. Schukraft
Tracking
 robust, redundant tracking from 60 MeV to 100 GeV
 modest soleniodal field (0.5 T) => easy pattern recognition
 long lever arm => good momentum resolution
 silicon vertex detector (ITS)
4 cm < r < 44 cm
 stand-alone tracking at low pt
 Time Projection Chamber (TPC)
90 cm < r < 250 cm
 Transition Radiation Detector (TRD) 290 cm < 370 cm
Dp/p (%) for
B=0.4T
TPC
Tracking efficiency
in TPC vs. multiplicty
59
TPC+ITS+TRD
Dp/p ~ 9% at 100 Geneva
GeV
2004 J. Schukraft
Particle Identification
 stable hadrons (p, K, p): 100 MeV < p < 5 GeV (few 10 GeV)
 dE/dx in silicon (ITS) and gas (TPC) + Time-of-Flight (TOF) + Cerenkov (RICH)
 decay topology (K0, K+, K-, L)
 K and L decays up to at least 10 GeV
 leptons (e, m), photons, h,p0
Alice uses ~ all
known techniques!
 electrons in TRD: p > 1 GeV, muons: p > 5 GeV, p0 in PHOS: 1 < p < 80 GeV
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Geneva 2004 J. Schukraft
Heavy Quarks
Hadronic charm: D -> Kp
 uses sec. vertex & PID
 acceptance to ~ 0 pt => stot
 full kinematic reconstruction
 => 'quark quenching'
 under study: D*, D, Bc, Lb, ...
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Energy Loss of Jets
 jet quenching = energy loss of leading particle
 lost energy appears in soft particles => change of jet fragmentation function !
 total jet-energy does not change ! => calorimeter only is insufficient
 ALICE handles on ‘jet quenching’
 leading hadrons
(0 - > 50 GeV)
 inclusive pt spectra & correlations
 identified hardons (p, p0, h,L, K)
 leading heavy quarks
(0 -> 20 GeV)
 inclusive b, c, D, B
 b, c tagging in jets (high pt electrons in TRD)
 hadron correlations
(5 –> 50 GeV)
 ‘same’ side, ‘opposite’ side
 jet fragmentation function
(40 -> 200 GeV)
 TPC,TRD,emcal
 jet correlations
( -> 50 GeV)
 g-jet (PHOS-emcal-TPC)
 jet1(emcal)-jet2(TPC)
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Past-Present-Future
 AGS/SPS: 1986 – 1994
 existence & properties of hadronic phase
 chemical & thermal freeze-out, collective flow,…
RHIC
 SPS: 1994 – 2003
 ‘compelling evidence for new state of matter
with many properties predicted for QGP’
 J/Y suppression (deconfinement ?)
 low mass lepton pairs (chiral restoration ?)
•
 RHIC: 2000 - ?
 compelling evidence -> establishing the QGP ?
 parton flow, parton energy loss
 however: soft ~ semihard; lifetime hadron ~ parton phase
 LHC: 2007 - ??
 (semi)hard >> soft, lifetime parton >> hadron phase
 precision spectroscopy of ‘ideal plasma ‘QGP
 heavy quarks (c,b), Jets, Y, thermal photons
LHC: will open the next chapter in HI physics
significant step over & above existing facilities
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THE place to do frontline research after 2007
Geneva 2004 J. Schukraft
Summary
 LHC is the ultimate machine for Heavy Ion Collisions
 very significant step beyond RHIC
 excellent conditions for experiment & theory (QCD)
 not only latest, but possibly last HIC at the energy frontier
 ALICE is a powerful next generation detector
 first truly general purpose HI experiment
 addresses most relevant observables: from super-soft to ultra-hard
 many evolutionary developments
 SSD, SDD, TPC, em cal, …
 some big advances in technology
 electronics, pixels, TOF, computing
Heavy Ion Community can look forward to
eventually
exploit this unique combination !
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