Onset of J/Onset of J/ Melting in Melting in

Quark-Gluon Quark-Gluon Fluid at RHICFluid at RHIC

Taku GunjiTaku GunjiCenter for Nuclear StudyCenter for Nuclear Study

University of TokyoUniversity of TokyoPaper: hep-ph/0703061Collaboration with:Hideki Hamagaki (CNS, Univ. of Tokyo), Tetsuo Hatsuda, Tetsufumi Hirano (Phys. Dept. Univ. of Tokyo)

1International Nuclear Physics Conference 2007@Tokyo, Japan, 2007/6/5

OutlineOutline• Physics Motivation • J/ suppression at RHIC• Hydro+J/ model• Results • Summary and Outlook

2International Nuclear Physics Conference 2007@Tokyo, Japan, T. Gunji

Physics MotivationPhysics Motivation• Quark-Gluon-Plasma (QGP)

– New state of QCD matter expected to be created at high temperature (Tc = 160-190MeV).

• Quarkonia suppression in QGP– Color Debye Screening

• T.Matsui & H. Satz PLB178 416 (1986)

– Suppression depends on temperature (density) and radius of QQbar system.

• TJ/ : 1.6Tc~2.0Tc • T, T’ : ~ 1.1Tc

– Serve as the thermometer in QGP.

Color Screening

cc

3International Nuclear Physics Conference 2007@Tokyo, Japan, T. Gunji

M.Asakawa and T.Hatsuda, PRL. 92, 012001 (2004)A. Jakovac et al. PRD 75, 014506 (2007)G.Aarts et al. arXiv:0705.2198 [hep-lat]. (Full QCD)

R.Rapp et al, EPJC43 (2005) 91 N. Xu et al, nucl-th/0608010

total

dissociation recombination

totalrecombination

dissociation

J/J/ Suppression at RHIC Suppression at RHIC• Two proposed scenarios:

– Gluon dissociation + recombination• Dissociation by thermal gluons supplemented by the regeneration

of J/ from ccbar coalescence – R. Rapp et al. [EPJC34, 91 (2005)], L. Yan et al. [PRL97,232301 (2

006)], R. Thews [NPA783 301(2007)], A.Andronic et al.[nucl-th/0701079], etc

4International Nuclear Physics Conference 2007@Tokyo, Japan, T. Gunji

A. Adare et al. (PHENIX) nucl-ex/0611020M. J. Leitch nucl-ex/0701021T. Gunji (PHENIX) nucl-ex/0703004

J/J/ Suppression at RHIC Suppression at RHIC• Two proposed scenarios:

– Sequential Melting of J/• Absence of the feed down J/ from c and ’ (30-40%) just above

Tc and melt of direct produced J/• F. Karsch et al., PLB 637 (2006) 75 etc

5International Nuclear Physics Conference 2007@Tokyo, Japan, T. Gunji

0 = 1 fm/cused here

SPS overall syst ~17%

PHENIX overall syst ~12% & ~7%

M. J. Leitch QM2006• J/ suppression at SPScan be understood from the melting of ’and c.• Stronger suppression in central Au+Au collisions compared to the feed down from c and ’.

Hydro+J/Hydro+J/ model model• First attempt for the study of sequential suppressio

n of charmonia at RHIC.– Incorporate J/, c and ’ into the evolution of matter.

• Evolution of matter : (3+1)-dimentional relativistic hydrodynamics – T. Hirano and Y. Nara, PRL 91, 082301, (2003)– T. Hirano and Y. Nara, PRC 69, 034908, (2003)– T. Hirano and K. Tsuda, PRC 66, 054905, (2002)– http://tkynt2.phys.s.u-tokyo.ac.jp/~hirano/parevo/parevo.html

• J/, c and ’ : impurity traversing through the matter

6International Nuclear Physics Conference 2007@Tokyo, Japan, T. Gunji

This study is focused on mid-rapidity data since :• hydrodynamical description of various observables is bestestablished in mid-rapidity (dN/dy, v2, pT dist., hard probes).

Modeling of J/Modeling of J/ suppressionsuppression

• Survival Prob. In the medium:

• Decay Width:

• Motion of J/free streaming

• Total Survival Prob.

• Free Parameters:

– (TJ/, T, fFD )

0

))((exp)( /// dxTxS JdisJJ

J/x0

(pT)

7International Nuclear Physics Conference 2007@Tokyo, Japan, T. Gunji

)(0),()( // JJdis TTTTT

0// )( xx JJ

,// )1( SfSfS FDJFDtotJ

• x0(Production point) is distributed according to the spatial Ncol distribution.• pT is distributed according tothe measured J/ distribution.• J/ azimuthal angle, , is flat (0 to 2).

Model resultsModel results• Reproduce experimental

SJ/tot(=RAA/CNM).

– Min. 2 at (TJ/, T, fFD) = (2.02Tc, 1.22Tc, 30%) 2

_

2

)(

)()(

partN partdatastat

parttheorypartdata

N

NSNS

Bar: uncorrelated sys.Bracket: correlated sys.

Onset of J/ suppressionat Npart ~ 160.( Highest T at Npart~160reaches to 2.02Tc.)

Gradual decrease of SJ/tot

above Npart~160 reflects that the transverse areawith T>TJ/ increases.

8International Nuclear Physics Conference 2007@Tokyo, Japan, T. Gunji

Sensitivity for TSensitivity for TJ/J/

• TJ//Tc = 1.9, 1.96, 2.02, 2.08, 2.14

• T = 1.22Tc and fFD=30%

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TJ/ = 2.14TcTJ/ = 2.08TcTJ/ = 2.02TcTJ/ = 1.96TcTJ/ = 1.90Tc

Theoretical SJ/tot

is very sensitive to TJ/

International Nuclear Physics Conference 2007@Tokyo, Japan, T. Gunji

2

1

Min. 2 (=0.86)

22 contour contour 2 contour (TJ/ vs. T) at fFD = 30%.

• Min. 2 = 0.86 at (TJ/, T)=(2.02Tc, 1.22Tc)

TJ/can be determined ina narrow regionaround 2.02Tc.

T is not well determined since it is correlated to fFD.

10T

/T

c

TJ/Tc

International Nuclear Physics Conference 2007@Tokyo, Japan, T. Gunji

SummarySummary• J/ suppression at mid-rapidity at RHIC was investig

ated using hydro+J/ model.– Dynamical and quantitative approach to the sequential char

monia suppression.

• Comparison of the experimental survival probability shows:– Observed suppression is described well with TJ/~2.02Tc.

– TJ/ can be determined in a narrow region.

– In accordance with the lattice QCD results.

11International Nuclear Physics Conference 2007@Tokyo, Japan, T. Gunji

Outlook Outlook • On Going issues:

– Prediction of J/ azimuthal anisotropy – More realistic treatment of Decay width – “Hot Wind” (Relative velocity dependence of TJ/)

• AdS/CFT Correspondence:

– Complete thermalization of J/(Free streaming)

• Will be done:– Study the J/ suppression at forward-rapidity with hydro+J/ mode

l.• Connection with gluon saturation (CGC).• Fine tuning of hydrodynamics at forward-rapidity is on going.

– Application to Cu+Cu system.

12International Nuclear Physics Conference 2007@Tokyo, Japan, T. Gunji

4/12 )1)(0()( vTvT meltmelt H. Liu, K. Rajagopal and U. A. Wiedemann : hep-ph/0607062.

Back Up SlideBack Up SlideMemoMemo

–Forward Suppression–Sudden suppression (v2, SAA vs. pT)–Smearing of Decay width(SAA)–Hot-wind (SAA,v2, SAA vs. pT)–Complete thermalization(SAA, v2)

Temperature fieldTemperature field• Normalized by Tc(=170 MeV)

b=2.1 fm (Npart=351) b=8.5 fm (Npart=114)

14International Nuclear Physics Conference 2007@Tokyo, Japan, T. Gunji

J/J/ Measurement at RHIC Measurement at RHIC• RAA vs. Cold Nuclear Matter effects.

RHIC CNM effects (abs = 0, 1, 2mb at y=0, y=2)R. Vogt et al., nucl-th/0507027

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d+Au data-driven prediction of CNM effects (not shown here):

R. Granier de Cassagnichep-ph/0701222

(dN/dy)AuAu

(dN/dy)pp x<Ncol> RAA =

absabs dependence dependence• Use abs=0,2 mb• Min. 2 at:

(TJ/, Tc, fFD)

=(2.00Tc, 1.02Tc, 35%)

for abs=0mb

=(2.02Tc, 1.02Tc, 15%)

for abs=2mb

TJ/ is insensitive to the nuclear absorptioncross section.

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ppTT dependence of S dependence of SAAAA

• Free Streaming– Survival Prob. Is almost flat as a function of pT

0-10% 10-20%

20-30% 40-50%

Survival Prob. Vs. pT (J/, , total) RAA vs. pT by PHENIX

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Prediction of J/Prediction of J/ v2 v2

0-10% 10-20%

20-30% 40-50%

v2. vs. pT (J/, , total)

v2=3%

v2=3%

J

Total(30% feed down)

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Smearing of Decay WidthSmearing of Decay Width• Decay Width :

decay= 0.5M[1+tanh((T/Tc-Tmelt/Tc))]

Decay Width

T/Tc

Survival Probability

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Hot WindHot Wind• Tmelt(v) = Tmelt(v=0)/sqrt(rel)

H. Lui, K. Rajagopal, U. A. Wiedemannhep-ph/607062-v3 Solid : Free streaming

Dashed : Hot wind

(TJ/, T, fFD) in hot wind =(2.08Tc, 1.36Tc, 35%)

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SSAAAA and v2 vs. pT in Hot and v2 vs. pT in Hot WindWind

• Tmelt(v) = Tmelt(v=0)/sqrt(rel)

0-10% 10-20%

20-30% 40-50%

Survival Prob. Vs. pT (J/, , total)

0-10% 10-20%

20-30% 40-50%

v2. Vs. pT (J/, , total)

v2=5%

v2=5%

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Complete ThermalizationComplete Thermalization• T>Tc: J/ moves according to fluid velocity vecto

r.• T~Tc: J/ freeze-out:

– Re-arrange the J/ px, py and pz using Boltzman Eq (in local fluid coordinate).

– Then boost J/ according to the fluid velocity vector.

322

)exp( pdTc

pmN

22

pT and v2 of flowed J/pT and v2 of flowed J/• J/ participating the flow

dN/dpT [A.U] v2

23

pT and v2 in complete thermalizpT and v2 in complete thermalizationation

• Only Directly produced J/

0-10% 10-20%

20-30% 40-50%

0-10% 10-20%

20-30% 40-50%

dN/dpT flow, non-flow, flow+non-flow flow, non-flow, flow+non-flowv2

24

RAA

(1.2<|y|<2.2) /RAA

(|y|<0.35)

1

RAA

0

1

0

Bar: uncorrelated errorBracket : correlated error

Forward rapidityForward rapidity• Stronger suppressionat forward rapidity.

– Gluon saturation (CGC)?• Leading to suppression of charm production

25

=2

Open charm yield in Au+Au @ 200 GeV

=0 ~60% Suppression patterndue to CGC

K. L. Tuchin hep-ph/0402298

(TJ/,T) = (2.02Tc,1.22Tc)FD = 30% (y=0), FD= (35-50)% (y=2)

Forward RapidityForward Rapidity• Experimental SJ/

tot (y=2)– CNM at y=0 & CGC suppression (y=2/y=0)

• Model SJ/tot (y=2)

– Hydro at y=2

• Need larger feed-down fraction at y=2.• Onset of suppression at Npart ~ 240?

• 2.02Tc is achieved at Npart~240 at y=2?

Further analysis is on going.

26

SJ/(y=0)=RAA/CNM(y=0,abs=1mb)

SJ/(y=2)=RAA/R(CGC)/CNM(y=0,abs=1mb)

Melting temperatureMelting temperature• Spectral analysis in quenched lattice.

J/ c

J/ c

Datta, Karsch, Petreczky & Wetzorke, hep-lat/0312037

Asakawa & Hatsuda, hep-lat/0308034

Tc~270 MeV

J/ may survive up to ~2Tc. c and y’ would melt at ~1Tc.

T. Hatsuda QM2006 (hep-ph/0702293)

27

Melting temperatureMelting temperature• Spectral analysis in full lattice (Nf=2).

T. Hatsuda QM2006 (hep-ph/0702293)

28

Jc

Aarts et al., hep-lat/0610065

Even with the light quarks, J/ may survive up to ~2Tc.

Tc~170 MeV

J/J/ suppression at RHIC suppression at RHIC• PHENIX experiment

– |y|<0.35 (ee) & 1.2<|y|<2.2 (mm)

Au+Au PHENIX Final (nucl-th/0611020)Cu+Cu PHENIX Preliminary

1

RAA

0

(dN/dy)AuAu

(dN/dy)pp x<Ncol> RAA =

29

Suppression by:x4 (y~0)x5 (y~2)

T. Gunji (PHENIX), QM06, nucl-ex/0703004

0 mb

3 mb

Low x2 ~ 0.003(shadowing region)

RdAu

Cold Nuclear Matter Cold Nuclear Matter (CNM) effects(CNM) effects

• Nuclear absorption + Gluon shadowing (anti-shadowing)

– Studied in d+Au collisions.

• Consistent with the shadowing picture.• Weak absorption cross section:

• abs=0-3mbR.Vogt, PRC71 054902 (2005)

• CGC also describes CNM effects.D. Kharzeev et al., NPA770 (2006) 40

30

pT [GeV]

Hydro. calculationHydro. calculation• (3+1) dimensional hydro. (,x,y,s)

– r, T, v(vx,vy) at (,x,y,s) 0 = 0.6 fm/c, Tc=170 MeV– Massless parton gas (u,d,s,g)– Tuned to reproduce dN/dh

31

Hydro data are open to public:http://tkynt2.phys.s.u-tokyo.ac.jp/~hirano/parevo/parevo.html

T.Hirano and Y.Nara, PRL91,082301(2003);T.Hirano and Y. Nara PRC69,034908(2004);T.Hirano and K.Tsuda, PRC66,054905(2002).

Hydro+Jet modelHydro+Jet model• Hydro+“hard probe” works.

– Identified hadron spectrum

– Back-to-back correlation

– Pseudo-y dependence of RAA

32

T. Hirano and Y. Nara PRL91 082301 (2003)

pT [GeV]

T. Hirano and Y. Nara PRC69 034908 (2004)

T. Hirano and Y. Nara PRC68 064902 (2003)

TTJ/J/ comparison comparison• This study shows TJ/~2.02Tc.

• Estimation of TJ/ in 3-falvor QCD from quenched lattice QCD.

3

/4/1

3

/

368/716

16f

f

Nc

qc

qc

J

Nc

J

T

T

T

T

T

T

33

= 1.7 = 270/170Asakawa & Hatsuda, hep-lat/0308034

This coincides with the resultobtained in this study.

05.23

/

fNc

J

T

T

c feed-down fraction

Feed down fractionFeed down fraction• Feed down fraction

– ~40% of J/ from c and ’

34

χ,1,2 J/ ~30%

΄ J/ 5.5%