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V. GrecoUniversità di Catania, ItalyINFN-LNS
Quark-Gluon Plasma Dynamics in ultra-Relativistic Heavy-Ion Collisions-II
Scuola Di Fisica Nucleare “Raimondo Anni” (IV corso)
Otranto, 1-5 giugno 2009
Hadronization Modified RAA-RCP-V2 for baryon and mesons
Ou
tlin
eHadronization and Open Heavy Flavor
Basic Theory of coalescence (phase –space) coal. vs fragm. - application to RHIC RAA – v2 and B/M in the coalescence mechanism
Heavy Quark interaction in the plasma problematic relation between RAA and v2 presence of heavy-light Qq resonances (lQCD) relevance of Hadronization mechanism
Surprises…
In vacuum p/ ~ 0.3 due to Jet fragmentation
Hadronization has been modifiedHadronization has been modified ppTT < 4-6GeV !? < 4-6GeV !?
PHENIX, PRL89(2003)
Baryon/MesonsBaryon/Mesons
Protons not suppressed
QuenchingQuenching
Au+Au
p+p
Jet quenching should affect both
suppression: evidence of jet quenching before fragmentation
)()(
)()()(
xx
xxx
DD
DD
E791 beam: - hard cc production;- c recombine with d valence from - D enhancement
Braaten, Jia, Mehen: Phys. Rev. Lett. 89, 122002 (2002)
Quark-Antiquark Recombination in the Fragmentation Region K.P. Das & R.C. Hwa: Phys. Lett. B68, 459 (1977):
Rapp and Shuryak, Phys. Rev. D67, 074036 (2003)
Leading Particle EffectReservoir of partons modifies hadronization
Similarly for
at ISR/Fermilab (late ‘70)
In HIC the resorvoir is the thermal bulk!
)(
)(
ucD
dcD
)( ud
=0 from LO fragmentation
beam
Hadronization in Heavy-Ion CollisionsInitial state: no partons in the vacuum but a thermal ensemble of partonsNo direct QCD factorization scale for the bulk: dynamics much less violent (t ~ 4 fm/c)dense parton systems no need for creation and splitting
Parton spectrum
H
Baryon
Meson
Coal.
Fragmentation
V. Greco et al./ R.J. Fries et al., PRL 90(2003)
Fragmentation: energy needed to create quarks from vacuum hadrons from higher pT
partons are already there $ to be close in phase space $
ph= n pT ,, n = 2 , 3 baryons from lower momenta (denser)
Coalescence:
ReCo pushes out soft ReCo pushes out soft physicsphysicsby factors x2 and x3 !by factors x2 and x3 !
Basic TheoryDiscard details of dynamics -> adiabatic approximation:instantaneous projection of initial state onto final cluster
- Go in the momentum frame- Neglect the transverse momentum- Neglect r,p correlations
Wab two parton distribution function
ababMbbaaba
abM qrprprWPd
dN,),,,(
,3
M(r,q) Meson wave function
All fairly good approximationsAt pT > 2 GeV/cxi light con momentum fraction
ababMbbbaaba
aM qrprfprfPd
dN,),(),(
,3
Approximation in FMNB (Hwa-Yang)
CM spin-isospin color factor
fragmenting parton:ph = z p, z<1
recombining partons:p1+p2=ph
Fries, QM’04
baMbbaabaMM xxPxfPxfdxdxVCPd
dN,)()(
3
Specific features of Reco in HICSpecific features of Reco in HICTp
th Aef /
Bpf jet
Tn
pn
nth eAC
1
nnjet pBC BpFjet
Tjet
nTjet
pF
pC )1(n
TpF
CSo eventually Fragmentation takes over …
Need of Coalescence + Fragmentation modelNeed of Coalescence + Fragmentation model
For baryons you will get the same as for mesonsOpposite to the suppression from fragmentation
P-> ∞ or m=0
1 ba xx
TPTPxTxPTp eeee //)1(// Parton Meson
ReCo is very effective for ReCo is very effective for thermal spectrathermal spectra::
More effective than Reco
ReCo is very effective for ReCo is very effective for power law power law spectraspectra::
Coalescence Fragmentation
“The best physicist in the USSR is Yakov Frenkel, who uses in his papers only quadratic equations. I am slightly worse,I sometimes use differential equations.”
L.D.Landau, quoted in BULLETIN OF THE American Mathematical Society 43, Number 4, October 2006, Pag. 563−565
Is coalescence ”too simple”?Is coalescence ”too simple”?
R.J. Fries, V. Greco, P. Sorensen - Ann. Rev. Nucl. Part. Sci. 58, 177 (2008)R.J. Fries, V. Greco, P. Sorensen - Ann. Rev. Nucl. Part. Sci. 58, 177 (2008)
Phase-Space Coalescence (GKL)
)(δ)...,...(),()π2(
σ 111
3
3
i2 iTTnnH
n
iiiq
iiH
T
H ppppxxfpxfpd
dpgpd
dN
)(δ)...,...(),()π2(
σ 111
3
3
i2 iTTnnH
n
iiiq
iiH
T
H ppppxxfpxfpd
dpgpd
dN
fq invariant parton distribution function thermal with radial flow (=0.5r/R) quenched minijets (GLV- L/ = 3.5)
fH hadron Wigner function 2
21
2
21
22
21
2 )()()(2
π9mmppxxf pxM 2
21
2
21
22
21
2 )()()(2
π9mmppxxf pxM
x =p (real free parameter different)
3D-geometry with radial flow space-momentum correlation
npQCD also encoded inquark masses (gluon dressing), mq=0.3 GeV, ms=0.475 GeV.
gH statistical factor color-spin-isospin
gg qq , suppressed by mass(g->qq no dire effects)
If <r2> is fixed results are nearly indipendent on the w.f. shape
ET ~ 740 GeV
T ~ 170 MeV(r)~ 0.5 r/R
GeVfm-3
dS/dy ~ 4800
Bulk matter consistent with hydro, experiments,
lQCD
Bulk matter consistent with hydro, experiments,
lQCD
Parton bulk matter parametersParton bulk matter parametersParton distributions
Experiments
lQCD Tc
like Hydro
L/
T=170 MeV
P. Levai et al., NPA698(02)
quenchedsoft hard
REALITY: one spectrum with correlation kept also at pT < 2 GeV
Hadron from coalescence may follow jet structure (away suppr.)
Coalescence at Coalescence at QCD QCD
phase transitionphase transition
Meson & Baryon Spectra
V. Greco et al., PRL90 (03)202302 PRC68(03) 034904R. Fries et al., PRL90(03)202303 PRC68(03)44902R. C. Hwa et al., PRC66(02)025205
Au+Au @200AGeV (central)ππρ
Proton suppression hidden by coalescence!
sh
GKL FMNB
ReCo dominates up to 4 (meson)6(baryon) GeV/c; Fragmentation + energy loss takes over above.
Baryon/Meson ratio
TAMU
FMNB Hwa-Yang
Strange particlesfrom a common
quark flow
Yields for baryon and mesons were not the only surprise at RHIC
Mass-dependence of v2(pT) suggests common transverse velocity field large
At higher pT v2 for Baryon=Mesons in both - hydrodynamics - jet fragmentation
Again surprise Baryon Again surprise Baryon ≠≠ Mesons : vMesons : v22 larger for Baryons larger for Baryons
Elliptic flow from Hydro
Coalescence carries another features …Coalescence carries another features …
/3)(p3v)(pv
/2)(p2v)(pv
Tq2,TB2,
Tq2,TM2,
Enhancement of vEnhancement of v22Coalescence scalingCoalescence scaling
n
p
nT
2V1
baryons
mesons
Molnar and Voloshin, PRL91 (2003)
2
22)2()(
T
T
q
T
T
M ppd
dNαp
pd
dN
3
22)3()(
T
T
q
T
T
B ppd
dNp
pd
dN
)2cos(v21φ 2
TT
q
TT
q
dpp
dN
ddpp
dN
Considering only momentum spacex - p correlation neglected
narrow wave function
v2 for baryon is larger and saturates at higher pT
(more baryons in plane)
v2q fitted from v2
GKL
Quark number scaling!
Again agreement with Again agreement with unexpected observationunexpected observation
No free parameter !No free parameter !
Better scaling vs KET/nq
0mmKE TT
It is related with energy conservation
- Mass of the hadrons is not relevant- rules out explanations blaming collective motion
- Confirmation v2 develops during partonic phase
Mass or quark number? (1020)
Confirmed also by K*(892) measurements
nq - not a mass effect
Most of flow is partonic
PHENIX, PRL (07)
Rcp~1 with large v2
Coalescence reverts the correlationBetween RAA & v2: both are enhanced
This rules out other explanations:Baryon junctions, hydro+jets
This effect is essential also for thestudy of charm quark interaction
P.Sorensen
RAA–RCP and v2 Correlation
Take home messages from the light sectorTake home messages from the light sector
Hadronization from 2-3 body phase SPACE (pT< 5-6 GeV):
dense medium decrease vacuum role massive quarks close in phase space
hadrons at pt comes from quarks pt/n (shift of soft scale)
Universal elliptic flow (dynamical quarks “visible”): carried by quarks enhanced by coalescence
R.J. Fries, V. Greco, P. Sorensen - Ann. Rev. Part. Sci. 58, 177 (2008)
Result are robust againstUncertainty in resonance,Wave function,higher Fock states. Energy conservation
Ok, but this is really too naive… !?Ok, but this is really too naive… !?1)1)Resonances Resonances (included in GKL)(included in GKL)
2)2)Wave function finite width Wave function finite width
3)3)GluonsGluons ALCOR, GKL : mass suppressed, quark dressing,
splitting Fries-Muller-Bass, PLB618 (05): Higher Fock States
4) 4) Energy ConservationEnergy Conservation not large 17% in GKL, resonances decay & v2
Ravagli-Rapp PLB655(2007) for v2(KET)
5) Entropy Conservation5) Entropy Conservation 15% like energy – mass, resonances, expansion
6) Relation to jet-like correlations6) Relation to jet-like correlations Consistent with ReCo- Fries et al., PRL94, but need
of a transport description
7) Space-momentum correlations affect v7) Space-momentum correlations affect v22
scalingscaling Pratt-Pal PRC71, Molnar nucl-th/0408044 , Greco-Ko
nucl-th/0505061,
Rapp-Ravagli arXiv:0806.2055
Less important at high pT
Stability of Reco results respect
uncertainties in their treatment
high pT the problem suppressed
by m/pT
but even at low pT
is not so drammatic
What happens What happens
to heavy quarks?to heavy quarks?
SPS
LHC
Zhu et al. (2006)
RHIC
Specific of Heavy QuarksSpecific of Heavy Quarks
mmc,bc,b >> >> QCDQCD produced by pQCD processes (out of equil.)
00~~ 1/m1/mc,bc,b << << QGPQGP they go through all the QGP lifetime
mmc,bc,b >> T >> T00 no thermal production no thermal production
eq eq >>QGPQGP >> >> q,gq,g sensitive to interaction (even at low pT)
m >>Tm >>T transport reduced to a Fokker-Planck
lQCD calculation of spectral function(quark loop damped)
Concept of potential V(r) <-> lQCD (also nrEFT) :
QGP <-> lQCDQGP <-> lQCD study sQGPstudy sQGP
Comparing mComparing mHQHQ to to QCD QCD and Tand T
Heavy Quarks in the Quark Gluon PlasmaHeavy Quarks in the Quark Gluon Plasma
2. Open Heavy FlavorD(cq) B(bq) because mq<<mc,b study their spectra means study the scattering of c,b in the medium
-> Spectra: RAA, v2(pT) of open heavy flavor
-> Quarkonium suppression
H. Satz
In the vacuum a potentialmodel gives very good result
Energy Loss for Heavy QuarksEnergy Loss for Heavy Quarks
Elastic Collisional energy loss - till now neglected in the light quark sector
Induced gluon emission - mass effect (“dead cone”)
In perturbative plasma physics:In perturbative plasma physics:
v=p/m >>1/g radiative (bremsstrahlung) is dominantAt 2TC it means p>>1 GeV for charm
pfpi
k
×
Scattering on resonant statesScattering on resonant states - suggestion from lQCD (spectral function & potential model)
pi pf
kac
g
c
What is measured till now is the single e What is measured till now is the single e
Single-Electron Decays D-Mesons
• bottom crossing at 5GeV !? • strategy: fix charm with D-mesons, adjust bottom in e±-spectra
llKD llDB
b/c similar to pQCD Cacciari, Nason, Vogt, PRL95(2005)
the lepton can be reconstructed
N. Armesto et al., PLB637(2006)362S. Wicks et al., nucl-th/07010631(QM06)
lQCD resonant (bound) states persistlQCD resonant (bound) states persistfor QQ and qq -> Qq (D-like) resonant scatteringfor QQ and qq -> Qq (D-like) resonant scattering
lQCD resonant (bound) states persistlQCD resonant (bound) states persistfor QQ and qq -> Qq (D-like) resonant scatteringfor QQ and qq -> Qq (D-like) resonant scattering
RRAA AA , v, v22 of single e – Jet Quenching of single e – Jet Quenching
Radiative energy loss not sufficient
sQGP: non perturbative effect qq
Main Challenge is the in-medium quark interactionMain Challenge is the in-medium quark interaction
A() 2()Asakawa
J/
J/ (p 0) disappearsbetween 1.62Tc and 1.70Tc
“Light”-Quark Resonances
1.4Tc
[Asakawa+ Hatsuda ’03]
Spectral function in lQCDSpectral function in lQCD
Studied in Potential model for J/
- Mannarelli, Rapp - PRC72 (Bruckner-like)
- Alberico, Beraudo, De Pace,
Molinari - PRD 72 & 75
t eq down to 5 fm/c at RHIC !
t eq down to 5 fm/c at RHIC !
Open-Charm Resonances in QGPOpen-Charm Resonances in QGP
• effective model with pseudo/scalar + axial/vector “D-like” mesons [chiral + HQ symmetry]
• cross section ISOTROPICISOTROPIC
Ok, but can it describe ROk, but can it describe RAAAA and v and v22??Ok, but can it describe ROk, but can it describe RAAAA and v and v22??
55 ,,,1
h.c.2
)v1(
cqG DDDcq L
pQCD
“D”QGP- RHIC
Equilibration time
As first test we used an effective model:
2 parameters: GD , mD
The modelThe modelHQ scattering in QGPHQ scattering in QGP
Langevin simulationin Hydro bulk
HadronizationHadronization
Coalescence + Fragmentation
Semileptonic decaySemileptonic decay
RAA & v2 of “non-photonic” e
(with b contamination )
sQGP
c,b quarks
K (D)
e
e
2
,2
,, )(
p
fD
p
pf
t
f bcbcbc
ppkwkdp ),(3
BDbcbcMqbcBDBD DfffC
Pd
Nd,,,,,3
,3c,bc,b
D (B)
23 ),(2
1ppkwkdD
Fromscattering
matrix
• Elastic pQCD
• LDcq
• T-matrix V(r)-lQCD
2Mw
T<<mHQ
Reson.
pQCD
frag)()(|)(|)2(
23
33
ccqqDDD pfpfqqd
pdg
pd
dNE
Prediction forPrediction for vv22 andand RRAAAA with resonance modelwith resonance model fq from , K
Greco,Ko,Levai - PRL90
coalescence+ fragment.
Hees, Greco, Rapp - PRC73(06)
• Simple upscaling of pQCD scattering cannot get
RAA-v2 (Teaney)
• coalescence increases both RAA and v2 (anti-
correlation)• It is worth to pursue the in-medium
resonance idea!
• Simple upscaling of pQCD scattering cannot get
RAA-v2 (Teaney)
• coalescence increases both RAA and v2 (anti-
correlation)• It is worth to pursue the in-medium
resonance idea!
QM’06
Diffusion coefficient from V(r) lQCDDiffusion coefficient from V(r) lQCD
Are there really Are there really hadronic-like resonances?hadronic-like resonances?
dT
dFTFV 1
11
Scattering states included:Singlet + Octet –triplet -sextet
Kaczmarek et al., PPS 129,560(2004)
VGTVT
qg
Q TS
• Equation closed with the equivalent equation in the light sector,here simplified with a constant m and
• Solve in partial wave expansion
VVlQCDlQCD gives resonance states! gives resonance states!
QQQQQ SSSS 0
Brueckner calculation
““Im T”Im T” dominated by meson and diquark channel
V(r) parametrizionby Wong, PRC72(2005)
•RAA is built in the early stage
•V2 in the later stage
• With lQCD- V(r):
less RAA and more V2
v2 generation delayed
lQCD
pQCD
Opposite T-dependence of Opposite T-dependence of F
rictio
n co
effic
ient
Drag and Diffusion from lQCD-Drag and Diffusion from lQCD-V(r)V(r)
ImT increase with temperature compensates
for decreasing scatterer density
One can get both RAA and v2
with no free tunable parameters:
Uncertainties:Uncertainties:- in the parametrizationof V(r)
-in the extraction of V(r) (U vs F)
B suppression larger than the first
expectation from LqbB
T-matrix calculation vs revised PHENIX dataT-matrix calculation vs revised PHENIX data
Essential ALICE (LHC) that will disentangle the two contributions
Hees-Mannarelli-Greco, PRL100 (2008)
Impact of hadronization mechanismImpact of hadronization mechanism
Hees-Mannarelli-Greco, PRL100 (2008)
Impact of hadronization
Improved RAA - V2 correlation
• toward a better agreement with data
• naturally merging into
a coalescence mechanism
Successful model so be more careful:Successful model so be more careful:
-Critical the choice between U=F-TS and F
- Improve consistency between coalescence and fireball evolution
- include radiative energy loss
- disentangle B and D contribution for a safe comparison
(ALICE-LHC)
From the point of view of the shear viscosity
lQCD-quenched
From RHIC to LHC?From RHIC to LHC?For min. bias.For min. bias.
Hydro bulk dN/dy=1100 (dN/dy=2200 for central)
Tinit= 3 Tc
Radial flow max=0.68
V2q light quark =7.5 % (hydro or numerology)
v2q(pT) from a cascade [ Ferini,Colonna, Di Toro,VG]
dN/d2pT of b,c from PYTHIA (ALICE PPR-JPG32)
Resonances off T>2TResonances off T>2Tcc
Calculation not done with lQCD, but h.c.2
)v1(
cqG DDDcq L
Borghini-Wiedemann,JPG3508)
From RHIC to LHC - RFrom RHIC to LHC - RAAAA
RHIC LHC
Suppression: RAA similar at RHIC and LHC!
Harder initial spectra at LHCResonance ineffective (“melted” T>2Tc) at early stage!
bottom
charm charm
bottom
For 3-body scattering opposite behavior !For 3-body scattering opposite behavior !
From RHIC to LHC – vFrom RHIC to LHC – v2 electrons2 electrons
v2 similar at RHIC and LHC!
Resonance effective when anisotropy is reduced Strong drag with the bulk flow at later stage! v2 slightly higher at low pt
RHIC LHC
from D only
ALICE
For 3-body scattering opposite behavior !For 3-body scattering opposite behavior !
Ideal Hydrodynamics works wellIdeal Hydrodynamics works well: good description of dN/dpT , v2(pT) mass-ordering & v2(pT)/ scaling
Jet-quenching (gluon-radiation) observedJet-quenching (gluon-radiation) observed: hadrons RAA <<1 and flat in pT
photons no quenching
Hadronization modifiedHadronization modified: B/M ratio consistent with quark coalescence v2(pT) scales with the number of quarks
pT <2 GeV
Heavy QuarksHeavy Quarks: not expected small RAA and large v2
RAA and v2 not accounted by jet quenching
2<pT <6 GeV
pT >6 GeV
Picking-up 3+1 results at Picking-up 3+1 results at RHIC RHIC
Perfect fluidPerfect fluid
Quarks degreesQuarks degreesof freedomof freedom
mT >1.5 GeV
Hadronic-likeHadronic-likeresonancesresonances
High opacityHigh opacity
We have not just a bunch of particles, but a We have not just a bunch of particles, but a transient state of high energy plasma withtransient state of high energy plasma with - Strong collective phenomena- Strong collective phenomena in conditions in conditions
similar to those 10similar to those 10-5-5 s after the Big Bang s after the Big Bang~~15 GeV/fm15 GeV/fm33 >> >> c c ~ ~ 350 MeV 350 MeV /s /s ~0.1 (lQCD)~0.1 (lQCD)
- Hadronization is modified - Hadronization is modified and thereand there
evidences ofevidences of quark degrees of freedom quark degrees of freedom
- Very opaque to jets- Very opaque to jets
-sQGP-sQGP
Picking-up four main results at RHIC Picking-up four main results at RHIC Viscous Hydrodynamics works well Hydrodynamics works well ((pptt<1.5 GeV<1.5 GeV)):
good description of dN/dpT , v2(pT) what’s the value of shear viscosity /s ? Bulk viscosity?
Jet-quenching (gluon-radiation) observed Jet-quenching (gluon-radiation) observed ((pptt>6 GeV>6 GeV)): all hadrons RAA <<1 and flat in pT, suppression is jet-like Mach-cone like correlation observed at pt<4 GeV What is the nature of the double peak structure? Elastic contribution, time dependendence, flavor changing…
Hadronization is modified Hadronization is modified ((1.5<p1.5<ptt<6 GeV<6 GeV)): B/M anomalous ratio and v2(pT) quark number scaling
is the v2(pt) consistent with the /s of sQGP?
Heavy quarks strongly interactingHeavy quarks strongly interacting: small RAA large v2 (hard to get both) pQCD fails
presence of hadronic-like resonances + need of coalescence need of lQCD spectral function, measurement of D and B
separately
What we have found and what we expect at LHC!What we have found and what we expect at LHC!
Develop a transport to control viscosities effect,
study the jet-bulk cone, chiral mass generation lQCD spectral function with widths for heavy hadrons Microscopic structure of sQGP (for HQ it’s closer) Determine shear viscosity and its temperature dependence (->LHC J/ suppression-regeneration is not clear (->LHC Mechanism of jet quenching is not clear (->LHC color effect) Scaling with quark number should persist Measure of d.of. By mean of thermal radiation
-> direct probe of lQCd equation of state new universal QCD phase at high energy CGC ? (-> LHC …
It will take a lot of other Raimondo Anni Nuclear Physics School…It will take a lot of other Raimondo Anni Nuclear Physics School…
Back-up
Energy ScanEnergy Scan
p+/ increase by 20%p/ decrease slight decrease
@62GeV without changing any @62GeV without changing any coalescence parameter!coalescence parameter!
LHCDepends on the balanceBetween jet-quenchingAnd radial flow
A wider range for Recois envisaged
Fries et al, EPJ(2005)
GKV,PRC71
Open Heavy FlavorOpen Heavy Flavor
to see Hidden Flavorto see Hidden Flavor
J/J/ & Y & Y D,B common underlying HQ distribution D,B common underlying HQ distribution
JJ// suppressionsuppression
cc bound state, M = 2.9 GeV
ee
Quarkonium suppression In a QGP enviroment:In a QGP enviroment: (Matsui-Satz ‘86)• Color charge is subject to screening of the medium
qq interaction is weakened (short range)• Linear string term vanish in the confined phase (T) 0 deconfinement (long range)
Coulomb Yukawa
D
r
effeff err
V
0 doesn’t mean no bound !
rrVconf )(
CTV /
CTr
Tc
4Tc
Screening Effect
• Abelian
• Non Abelian
r
TgV cc
4
)(
4
2
One loop pQCD
13/2 TgD)(
2
)(
2
1 T
r
eff Der
T
rH
0)(
dr
rdEBohr
eff
D r2.12.1
Bound state
Bound is not Tc !
MeVT eff
Bound 2109
2
84.0
MeV150
Associated suppression of charmonium resonances ’c , …
as a “thermometer”, like spectral lines for stellar interiors
NUCLEAR ABSORBTIONNUCLEAR ABSORBTION pre-equilibrium cc formation time and absorbtion by comoving hadrons
HADRONIC ABSORBTIONHADRONIC ABSORBTION rescattering after QGP formation
DYNAMICAL SUPPRESSIONDYNAMICAL SUPPRESSION (time scale, g+J/ cc,…)
pA (models)abs ~ 6 mb
DDhJ ,...),,(/
J/
J/
J/
J/ J/
J/
’
’
J/
J/
J/
J/ J/
J/
’
’
J/
J/
J/
J/…
…
…
…
…
J/
J/
J/
J/ J/
J/
Il mezzo (confinato/deconfinato) influisce in Il mezzo (confinato/deconfinato) influisce in modo diverso sui differenti stati del charmonio.modo diverso sui differenti stati del charmonio.
Proprieta` diverse (energia di legame, raggio) Proprieta` diverse (energia di legame, raggio) implicanoimplicano
sezioni d’urto diverse per interazioni con adroni e sezioni d’urto diverse per interazioni con adroni e diverse temperature di dissociazione nel plasma. diverse temperature di dissociazione nel plasma.
dirdirdirJJ SSSS '// 1.03.06.0
Spiegazioni ?Spiegazioni ? Sono stati proposti modelli che riescono a Sono stati proposti modelli che riescono a
riprodurre piuttosto bene la soppressione riprodurre piuttosto bene la soppressione osservata assumendo la formazione di una fase osservata assumendo la formazione di una fase deconfinata in urti centrali Pb-Pb e In-In.deconfinata in urti centrali Pb-Pb e In-In.
Nel 2005 sono stati pubblicati anche i dati Nel 2005 sono stati pubblicati anche i dati sperimentali di RHIC (PHENIX)sperimentali di RHIC (PHENIX)
Una grossa sorpresa e` stata l’osservare una Una grossa sorpresa e` stata l’osservare una soppressione confrontabile con quella misurata ad soppressione confrontabile con quella misurata ad SPS e praticamente indipendente dall’energia !SPS e praticamente indipendente dall’energia !
(NB: A RHIC attenzione alla rigenerazione !)(NB: A RHIC attenzione alla rigenerazione !)
Comparison to theory (II)Comparison to theory (II)
Models that were successful in describing SPS datafail to describe data at RHIC
- too much suppression -
Comparison to theory (III)Comparison to theory (III)
Adding recombination: much better agreement with the data
2
ψ/ ccJ NN
Spiegazione con il QGPSpiegazione con il QGP La soppressione osservata a SPS e RHIC e` dovuta esclusivamente La soppressione osservata a SPS e RHIC e` dovuta esclusivamente
alla rimozione delle componenti alla rimozione delle componenti ’ e ’ e cc , perche’ la densita` di , perche’ la densita` di
energia raggiunta non e` ancora sufficiente a dissolvere la J/energia raggiunta non e` ancora sufficiente a dissolvere la J/ diretta:diretta:
La soppressione della J/La soppressione della J/ si vedra` a LHC ! si vedra` a LHC !
Or now recombination is large at RHIC and at LHC we will see Or now recombination is large at RHIC and at LHC we will see J/J/enhancementenhancement
dirdirdirJJ SSSS '// 1.03.06.0
Spectral function from lQCD and improvement of potential models Will be essential together with the LHC data
Regeneration is revealed in : - pt spectra - elliptic flow
Quarkonium Heavy-Quark
Till now we have looked only at J/ yieldyield, but thanks to such a strong collective dynamics …
Greco, Ko, Rapp PLB595(2004)
Jcoal.
No feed-downNo direct contr.
pT- Quarkoniafrom regeneration
consistent with Open!?
Suppression only
v2Y from v2D :measure of
Ncoal/NINI
Coalecence only
Summary about heavy flavorSummary about heavy flavor
RAA - v2e correlation for HQ entails:
- no pQCD T dependence of c and b diffusion - presence of Q-q resonances (start link to lQCD) - Relevance of hadronization by coalescence
Similar RAA & v2 at RHIC- LHC:
- if from RHIC to LHC a new QGP phase is
created !
New stage of Quarkonium probe : - Consistency of D and J/Y @ RHIC:
dN/dpT & v2 (pT) decisive contribution to
J/ issues
Charm close to thermalization (th ~ QGP) at RHIC energy
Greco, Ko, Rapp-PLB595
Open FlavorOpen Flavor
HiddenHidden
)(v
/
,2
,
Tbc
Tbc
p
dpdN
LHCLHCALICEALICE
This will be one of the field that will develope more at LHC!