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Michel GONIN. Lecture 2 on J/ suppression. 1. Charmonium bound states. 2. Screening effects in the plasma. 3. Experimental results. 4. Life (for physicist) is tough. l D depends on the temperature. . quarkonia. q. q. Lattice QCD. ’. . T > T c. . = 0. - PowerPoint PPT Presentation
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Lecture 2 on J/ suppression
1. Charmonium bound states
2. Screening effects in the plasma
3. Experimental results
4. Life (for physicist) is tough
Michel GONIN
D depends on the temperature
r
rZer D )/exp(
)(
204 en
kTD
qq quarkonquarkoniaia
Satz et al.Satz et al.
Successive (vs. temperature) melting for the Successive (vs. temperature) melting for the quarkoniaquarkonia
T > TT > Tcc = 0
Lattice QCD
’
Signals for the DeconfinementSignals for the Deconfinement
Satz et al.
1 32 4 5
Suppression
ψ’ χ ψ
’
Quakonia Quakonia ScreeningScreening
ψ’
40 Tc 1.0
χ 240 Tc 1.0
ψ 670 1.4 Tc 3.8
’ 640 1.4 Tc 3.8
1100 3.2 Tc 100
Bounding Energy Bounding Energy (MeV)(MeV)
Screening Screening TemperatureTemperature
Energy densityEnergy density (GeV/fm3)(GeV/fm3) ε
ε
NA50 at CERNNA50 at CERN
Electromagnetic Electromagnetic desintegrationdesintegration
cc
cc
J/J/ e e++ee–– identified in RICH
and EMCal– || < 0.35
– p > 0.2 GeV
J/J/μμ++μμ––
identified in 2 fwd spectrometers– 1.2 < || < 2.4
– p > 2 GeV
How does PHENIX see the J/How does PHENIX see the J/ ? ?
Cathode-strip chambers = 24000 voies analogiques / bras Pistes = 1cm (barycentre) = 100m Bruit/Signal ~ 1% ADC 11 bits, 4 échantillons temporels à 100 ns
d-Au d-Au samplesample
Mass Resolution ~ 100 MeV
Di-electron analysis Di-muons analysis
Mass Resolution ~ 150 MeV
peripheral
central
NA50 at CERN …NA50 at CERN …
Short history of RHICYear Ions sNN Luminosity Detectors J/
2000 Au-Au 130 GeV 1 b-1 Central (electrons)
0
2001 Au-Au 200 GeV 24 b-1
Central 13 + 0 [1]
2002 p-p 200 GeV 0.15 pb-1 + 1 muon arm 46 + 66 [2]
2002 d-Au 200 GeV 2.74 nb-1
Central 300+800+600
2003p-p 200 GeV 0.35 pb-1 + 2 muon arms
100+300+120
2004 Au-Au 200 GeV 300 nb-1 ! taking data ! ~400+2x1600
NA5NA500
Ordinary Ordinary absorptionabsorption
ANOMALOUS
J/SUPPRESSION
EZDC (GeV)
Beam
With E T With EZCD
Satz et al.
Suppression
1 32 4 5
ψ’ χ ψ
’
ε
Satz et al.
Suppression
1 32 4 5
ψ’ χ ψ
’
ε
NA50NA50
ψ’ χ ψEvidence forEvidence for
Screening Screening EffectsEffects
NA50NA50
Satz et al.
Suppression
1 32 4 5
ψ’ χ ψ
’
ε
ψ’
DECONFINEMENT !!DECONFINEMENT !!!!
Heavy Ion Heavy Ion PhysicsPhysics
High High Energy Energy PhysicsPhysics
Heavy Ion
Physicists
Life is Life is toughtough
ψ’
40 Tc 1.0
χ 240 Tc 1.0
ψ 670 1.4 Tc 3.8
’ 640 1.4 Tc 3.8
1100 3.2 Tc 100
not exactely not exactely ……
t = 0
J/ψ J/ψ 10 fm/c t 20 fm/c
- Screening effects
- hard gluon scattering
Deconfinement
WITH PLASMA
Hadronization
c c
t 2 fm/c mixed
phasec d
c d
Hadronic gas
Freeze-out
D D t 5 fm/c
c c
Regeneration : answer from Regeneration : answer from RHIC RHIC
R.Rapp
S-UPb-Pb
Satz et al.
Suppression
1 32 4 5
ψ’ χ ψ
’
ε
ψ’
Heavy Ion
Physicists
Life is Life is toughtough
J/ ++ protons (neutrons) open charm
D-
D+
CHARMONIA DISSOCIATIONCHARMONIA DISSOCIATION
J/J/
pp
Glauber absorption Glauber absorption modelmodel
Rarely produced (no multi-production)Rarely produced (no multi-production)
Uniforme (inside the nucleus) production Uniforme (inside the nucleus) production probabilityprobability Short (Short ( 1fm/c) formation time 1fm/c) formation time
L = path lengthL = path length
abs.
straight line trajectoriesstraight line trajectories
model
data
Does it Does it work ??work ??
Yes
J/
Glauber absorption Glauber absorption modelmodel
Glauber absorption Glauber absorption modelmodel
antiproton
CERN :CERN : abs. = 21.4 = 21.4 2 2 mbmb
BNL :BNL : abs. = 24.8 = 24.8 3 3 5 5 mbmb
Glauber absorption Glauber absorption modelmodel
Drell-Yan
no no absorption absorption
abs. 0 0
Drell-YanDrell-Yan
J/
J/
Ordinary Ordinary dissociatiodissociationn
p-A p-A p-p p-p
Heavy Ion
Physicists
Life is Life is toughtough
t = 0
10 fm/c t 20 fm/c
- Screening effects
- hard gluon scattering
Deconfinement
WITH PLASMA
Hadronization
c c
t 2 fm/c mixed
phasec d
c d
Hadronic gas
Freeze-out
D D t 5 fm/c
c c
t = 0
0.3 fm/c t 0.9 fm/c J/ψ
c c
1.5 fm/c t 2 fm/c
10 fm/c t 20 fm/c
c c + nucleons
J/ψ + nucleons
J/ψ + ,,,…
Nucleons
Comovers
WITHOUT PLASMA
produced hadrons
Freeze-out
Failure of the comover calculations to reproduce the data
Satz et al.
Failure of the comover calculations to reproduce the data
Gale et al.
640 MeV
-135 MeV
385 MeV
comvabsσ Comover
s
UrQMD
Wong et al.
comvabsσnucl
absσ = 6.2 mb = 0.6 mb
A. Capella
comvabsσnucl
absσ
6.2 mb 0.6 mb
5.0 mb 1.2 mb
4.0 mb 2.0 mb
Failure of the comover calculations to reproduce the data
20020033
The comover calculations to reproduce the data
comvabsσnucl
absσ = 4.0 mb 1.0 mb
Capella
Cassing
S+U
Capella 2002Capella 1998
the comover calculations can reproduce the data
the comover calculations to reproduce the data
20022002
THE THE COSTCOST
comvabsσ 1.0 mb ncomv 1 / fm3
the comover calculations to reproduce the data
20022002
THE THE COSTCOST
comvabsσ 1.0 mb
the comover calculations to reproduce the data
20022002
THE COSTTHE COSTncomv 1 / fm3
Cassing et al
B.Muller et al
Heavy Ion
Physicists
Life is Life is toughtough
Structure functions of the proton or Structure functions of the proton or neutronneutron
Diffusion cross sectionDiffusion cross section
dd A A FF11(x(x) + B ) + B FF22(x)(x)
FF11(x)(x) = 0.5 = 0.5 ii eeii22 n ni i (x(x) ) i = partonsi = partons
FF22(x)(x) = = 2x 2x
FF11(x)(x)
Cross section for Drell-Yan Cross section for Drell-Yan productionproduction
dd22 D [ D [FFqq(x(x11))FFqq (x(x22) ) + + FFqq(x(x22))FFqq
(x(x11)])]
F(x)F(x) F(x,F(x,Q2)) for low for low Q2 (QCD non-(QCD non-perturbative)perturbative)
gluogluonsns
Inside a proton ….
Influence of the « cold » nuclear medium on Influence of the « cold » nuclear medium on the quark (gluon) momentum distribution the quark (gluon) momentum distribution within a nucleon ?within a nucleon ?
PP11
,, DD xx11 PP11
xx22 PP11PP22
gg
gg, , BB
xxgluongluon m m (m(m))//ss
xxgluongluon == fraction of total fraction of total momentummomentum
s s xx EnergEnergyy
Kimber et Kimber et al.al.
Gluon shadowing dans A Gluon shadowing dans A = 208= 208
Gluons distribution Gluons distribution
inside the nucleus inside the nucleus ????
xxgg
xxgg
Eskola et al.Eskola et al.
Structure fonctionsStructure fonctionsratio pp/pAratio pp/pA
Influence of the « cold » nuclear medium on Influence of the « cold » nuclear medium on the quark (gluon) momentum distribution the quark (gluon) momentum distribution within a nucleon ?within a nucleon ?
RHICRHICCERNCERN
x
LHCLHC
Deuteron Gold
• In PHENIX, J/ mostly produced by gluon fusion, and thus sensitive to gluon pdf
• Three rapidity ranges probe different momentum fraction of Au partons
– South (y < -1.2) : large X2 (in gold) ~ 0.090
– Central (y ~ 0) : intermediate X2 ~ 0.020
– North (y > 1.2) : small X2 (in gold) ~ 0.003
d
Au
X1 X2
J/ inNorthy > 0
X1X2
J/ inSouthy < 0
rapidity y
ppdAR 1972/
Low x2
High x2
1972 ppdA
High x2
~ 0.09
Low x2
~ 0.003
Broadening comparable to lower energy (s = 39 GeV in E866)
RdA
• Total cross section (preliminary)
BR pp = 159 nb ± 8.5 % (fit) ± 12.3% (abs)J
Vogt, PRL 91:142301,2003 Kopeliovich, NP A696:669,2001
Low x2 ~ 0.003(shadowing region)
compared to lower s
Data favours (weak) shadowing + (weak) absorption ( > 0.92)With limited statistics difficult to disentangle nuclear
effects
RdA
XF = Xd - XAu
• Not universal versus X2 : shadowing is not the whole story.
• Same versus XF for diff s. Incident parton energy loss ? (high Xd = high XF)
• Energy loss expected to be weak at RHIC energy.
X2 (in gold)E866: PRL 84, 3256 (2000)NA3: ZP C20, 101 (1983)
NA5NA500
Ordinary Ordinary absorptionabsorption
ANOMALOUS
J/SUPPRESSION
3232S - S - 238238UU
208208Pb - Pb - 208208PbPb
5858Fe - Fe - 5858FeFe
197197Au - Au - 197197AuAu
1616O - O - 1616OO
4040Ar - Ar - 4040ArAr
208208Pb – Pb – 208208PbPb
RH
ICR
HIC
LH
CLH
CS
PS
SP
S
11001100
640640 ’ ’
670670J/J/4040 ’’
Binding Binding Energy Energy (MeV)(MeV)
déconfinement«screening » of J/Psi et Upsilon-prime
QUARKONIA SUPPRESSION