quarkonia production in high energy heavy ion collisions at rhic t. gunji center for nuclear study...

Quarkonia Production in High Energy Heavy Ion Collisions at R

HIC

T. GunjiCenter for Nuclear Study

University of Tokyo

Strangeness in Quark Matter 2008: T. Gunji Title 1/25

Introduction J/ Measurement at RHIC

Fate of J/ in Heavy Ion collisionsJ/ Production in d+Au collisions

Cold nuclear matter effectJ/ Production in A+A collisions

Hot and dense medium effectFuture perspectivesSummary

Strangeness in Quark Matter 2008: T. Gunji Outline 2

Outline

PHENIX|y|<0.35 , di-electron pairs1.2<|y|<2.2, di-muon pairs2002 ~

STAR |y|<1.0, di-electron pairs

Dedicated trigger Single ET Trigger Double electron trigger

2005~

Strangeness in Quark Matter 2008: T. Gunji Introduction 3

J/ Measurement at RHIC

p+p: PRL 92, 051802 (2004), PRL 96, 012304 (2006) PRL 98, 232002 (2007)d+Au: PRL 96, 012304 (2006) , PRC 77, 024912 (2008)Au+Au: PRC 69. 014901 (2004), PRL 98, 232001 (2007)Cu+Cu: PRL 101, 122301 (2008)


J/ Mass spectra 2005 p+p 2008 d+Au

2004 Au+Au 2005 Cu+Cu

Successful operation of RHIC, PHENIX and STAR gain J/ statistics every year!!

M.J. Leitch for the PHENIX collaboration, arXiv:0806.1244 [nucl-ex]


Other Quarkonia Measurement Upsilon

c and ’

PHENIX Preliminaryp+p QM05

p+p QM06

eePHENIX

Run 5 200GeV p+p

STARRun 5 200GeV p+p

=10.24/8

’e+e-

p+p 200GeV, Run-6

PHENIXRun 5 200GeV p+p

c J/+


J/ in p+p from STAR and PHENIX

PHENIX and STAR results are consistent.

•High statistics from PHENIX•High pT from STAR

PHENIX PRL 98, 232002 (2007)

STAR arXiv: 0806.0353 [nucl-ex]

PHENIX PRL 98, 232002 (2007)STAR arXiv: 0806.0347 [nucl-ex]

M. J. Leitch RHIC&AGS Meeting 2008

Source of J/ :c J/ 20-40%’ J/~8%BJ/~4% (@RHIC)


Feed down to J/from higher states

20% ~ 40% from c ~ 8% from ’S. X. Oda QM2008

STAR arXiv: 0806.0347 [nucl-ex]

Strangeness in Quark Matter 2008: T. Gunji Fate of J/y in Heavy Ion Collisions 8

Fate of J/ in Heavy Ion Collisions Initial stage

• Gluon shadowing • Gluon saturation (CGC)

Nuclear Matter •Nuclear absorption •Cronin effect

Hot and dense medium•Color screening•Dissociation by gluon •Regeneration from heavy qqbar pairs

absLe

Color Screening

cc

[Bhanot+Peskin ’79]

ccbar~ 0.06fm,form ~ 1fm/c

Initial + nuclear matter effect = “CNM effect”

Strangeness in Quark Matter 2008: T. Gunji J/ Production in d+Au 9

J/ in d+Au collisions at RHICInitial stage effect

Gluon shadowing depletion of gluon PDF in small x region

Color Glass CondensateGluon saturation from non-linear gluon interactions for the high density at small x.

Nuclear matter effect Nuclear absorption

Dissociation of J/or pre-resonance by spectators.

absLe

σabs = 4.18 ± 0.35 mb at SPS

arXiv:0802.0139

anti-shadowin

gshadowing

J/ in d+Au @ PHENIX:•-2.2<y<-1.2 : x~0.09• y~0 : x~0.02• 1.2<y<2.2 : x~0.003

Strangeness in Quark Matter 2008: T. Gunji J/ Production in d+Au 10

RdAu vs. Rapidity

Tendency is well agreement within shadowing predictions. EKS/NDSG Model (+21 process, g+gJ/) EKS + 22 process (g+gJ/+g, extrinsic), less rapidity dep.

Break up cross section is 2~4mb. Need more statistics to constraint cold matter effects.

PHENIX PRC 77, 024912 (2008)

PHENIX revisits systematic error evaluation.

E. G. Ferreiro et al. arXiv:0809.4684[hep-ph]

Details: L. A. Linden Levy (session 5), Raphaël Granier de Cassagnac (Session 9)

Strangeness in Quark Matter 2008: T. Gunji J/ Production in A+A 11

J/ in A+A collisions at RHIC To extract medium effects

Color screening Dissociation by gluons Recombination

Color Screening attraction between QQbar pairsare reduced in QGP.

no-bound or loosely bound (b⇊) suppression depends on T() and RQQbar

Color Screening

cc

[Bhanot+Peskin ’79]

S. Digal, F. Karsch and H. SatzPotential Model & lattice simulations

TJ/ ~ 1.2Tc [A. Mocsy et al, PRL 99(2007)211602, HP’08]Tc ~ 2Tc [T. Umeda, PRD. 75, 094502 (07)]

Experimental measurementwill be important.


J/ in A+A collisions at RHIC Dissociation by gluons

Gluo-effect : 　 J/+gccbar Quasifree : J/+gccbar+g depends on binding energy inthe medium ( Color screening).

Recombination recombination from uncorrelated ccbar pairs. Enhancement of yield. Negligible at SPS. But not at RHIC. Huge at LHC. Charm production needs to be understood.

R. Rapp et al. arXiv:0807.2470 Eur.Phys.J.C43:91-96,2005

A. Andronic et al. NPA 789 (2007) 334


Back to J/ suppression at SPS

F. Karsch et al., PLB, 637 (2006) 75

Pb-Pb @ 158 GeVR. Rapp et al. Phys.Rev.Lett.92:212301,2004.

Two scenarios to describe J/ suppression at SPS

Dissociation + Recombination a little recombination contribution

Sequential Melting Direct J/ unlikely to melt. c and ’ are screened. Absence associated feed down to J/.


J/ suppression at RHIC (RAA)

RAA (1.2<|y|<2.2) < RAA (|y|<0.35) ~ RAA at SPS (0<y<1)

Recombination compensates stronger suppression? Cold matter effects? Stronger at forward rapidity? +Melting of only higher states (+ small fraction of direct J/?

|y|<0.35

1.2<|y|<2.2PRL.98, 232301 (2007)arXiv:0801.0220

PRL.98, 232301 (2007)PRL 101, 122301 (2008)


First, check CNM effects in A+A

PHENIX PRC 77, 024912 (2008)

PHENIX revisits systematic error evaluation.

Even though error is large, CNM effect is similar between both rapidities Extrinsic treatment (g+gJ/+g) gives stronger CNM at forward. Stronger suppression than expectations from CNM effect

Need more d+Au data to constraint CNM effects.

E.G.Ferreiro et al. arXiv:0809.4684

Extrapolation from d+Au collisions

Details will be talked by Raphaël Granier de Cassagnac (Session 9)


Dissociation + RecombinationX. Zhao, R. Rapp et al. arXiv:0712.2407 A. Andronic et al. NPA 789 (2007) 334, QM08

Stronger suppression is supplemented by recombination. ~x50 larger cross section of charm pairs at RHIC than at SPS.

Less recombination at forward rapidity due to smaller cross section of charm at forward rapidity Need to understand charm production.


Sequential MeltingF. Karsch et al., PLB, 637 (2006) 75

Lattice calculations show TJ/~2Tc ≫ Tc~T’~1.1Tc. J/ suppression at SPS:

melting of c and ’ and associated absence of feed down to J/

J/ suppression at RHIC can be described by sequential melting.direct J/ suppression starts around Npart~160 (T ~ 2Tc in hydro). reflect temperature field of the medium.

Similar suppression at forward. Additional CNM effects at forward?

Hydro + J/T. Gunji et al. PRC 76:051901,2007


CGC for J/ Production in A+A

D. Kharzeev et al. arXiv:0809.2933

dN/dy

Normalization factor is from overall fit to data. can be fixed using high statistic d+Au data.

Rapidity shape can be described by CGC. Final state effect is roughly rapidity independent.

CGC (cold matter effect) can describe hadron production in A+A collisions at forward rapidity at RHIC.


pT dependence of suppression Combining PHENIX & STAR data reach higher pT.

Many effects are here…

Cronin effect enhance higher pT

(anti-)Shadowing enhance pT

Recombination enhance lower pT

Screening & dissociation

suppress lower pT hot-wind scenario

suppress high pT

M. J. Leitch RHIC&AGS 2008

RAA for high pT J/ = 0.9 0.2 but consistent with RAA ~ 0.6 (low pT) Need to have more data to disentangle:

Cronin effect ( Need more d+Au data, First!!) Hot and dense medium effect. Feed down from B decay.

33

J/ v2 at RHICStrangeness in Quark Matter 2008: T. Gunji J/ Production in A+A 20

First J/ flow measurement by PHENIX. v2 = -10% 10 % 2% 3% (mid-rapidity)

J/’s from recombination should inherit large charm-quark flow.but difficult to see flow of J/due to large error bars. Negative to positive v2 Just Mass ordering? Charm collectivity. Need more data and need to understand with charm quark v2.

NA50 HP08PRELIMINARY Run-4Run-7

Rapp & van Hees, PRC 71, 034907 (2005)

minimum-bias

D. Krieg et al. arXiv:0806.0736

33

What we will need?Strangeness in Quark Matter 2008: T. Gunji Future perspectives 21

Understand CNM effects. Shadowing/CGC, Absorption, Cronin effectMore data from d+Au collisions : 2008 d+Au data

Understand recombination contributionCharm production (vs. y, pT) in p+p/d+Au/A+A Detector Upgrade: VTX/FVTX (PHENIX), HFT/MRPC/DAQ (STAR)

Other quarkonia (c, ’ and ϒ family) in A+AFeed down/sequential melting/screeningDetector Upgrade: NCC (PHENIX)

Of course, high statistics of J/in A+AHigh pT/v2Luminosity advance of RHIC, RHIC-2

LHC!!Recombination ≫ complete screening for J/Measurement of ϒ family with higher statistics. ϒ(2S) vs. J/

33

2008 d+Au collisionsStrangeness in Quark Matter 2008: T. Gunji Future perspectives 22

PHENIX Run8 d+Au ~ 30 x Run3 d+Au

57,030 J/ (~73,000 from all

data)

4,369 J/ ee(~6,000 from all data)

59 nb-1

63 nb-1

33

Detector UpgradeStrangeness in Quark Matter 2008: T. Gunji Future perspective 23

VTX/FVTX/NCC (PHENIX)

HFT/MRPC/DAQ(STAR)

’ measurement with reduced combinatorial background + sharper mass resolution• C measurement with photon in NCC• precise open-heavy measurements to constrain regeneration picture

STAR DAQ1000 FEET. Hallman, QM08

33

Luminosity advance of RHIC, RHIC-2

Strangeness in Quark Matter 2008: T. Gunji Future perspectives 24

# x100#J/

max

min

100,000 J/ 250 13,000 J/ ee100 ϒ ee per year at highest RHIC luminosities (Au+Au, MB)

max

min

J/ &

A. D. Frawley et al. arXiv:0806.1013 [nucl-ex]M. Blaskiewicz RHIC&AGS Meeting 2008

33

SummaryStrangeness in Quark Matter 2008: T. Gunji Summary 25

J/ Production at RHIC has been measured in p+p, d+Au, A+A collisions at RHIC.

There are many interesting observations.Similar suppression between at RHIC (y=0) and at SPSStronger suppression at forward than at mid-rapidity.

Dissociation+Recombination/Sequential Melting+gluon saturation

Large uncertainty on cold nuclear matter effects prevents a firm conclusion. More d+Au data.

Other observables (pT dist., v2) with high statistics will be helpful.

First, 2008 d+Au data will open the next door. Stay tuned!! Future will tell us more of J/ story.

Strangeness in Quark Matter 2008: T. Gunji Physics Motivation 2

Back up slides


Initial state effectGluon Shadowing

Depletion of Gluon PDF in nuclei

Color Glass CondensateGluon saturation from non-linear gluon interactions for the high density at small xLarger effect for heavier nuclei

Eskola et al. NPA696 (2001) 729gluons in Pb / gluons in p

x

AntiShadowing

Shadowing


Color Screening

Color Screening

cc

Attraction between ccbar pairs is reduced in QGP

T. Matsui and H. Satz (1986) This leads the suppression of quarkonia yield.

Melting temperaturesS. Digal, F. Karsch and H. SatzPotential Model & lattice simulations T/TC 1/r [fm-1]

(1S)

J/(1S)

c(1P)

’(2S)

b’(2P)

’’(3S)

A.Mocsy HP2008

1.2

2

Difference in melting temperatures between calculations. TJ/ ~ 2Tc, Tc~T~1.1Tc

TJ/ ~ 1.2Tc [A. Mocsy et al, PRL 99(2007)211602, HP’08]

Tc ~ 2Tc [T. Umeda, PRD. 75, 094502 (07)]

Experiment and Measurement will be important.

This is due to Feed down and Different Tmelt

Suppression pattern will tell us: Achieved temperature of the medium Spatial distribution of temperature Feed down fraction.

Nuclear AbsorptionDissociation of J/ or pre-resonance by spectators.

Cronin effectMultiple scattering of partons

11

Cold Matter Effects

J/ψL

σabs = 4.18 ± 0.35 mb

at SPS

absLe



Gluon dissociation Destruction of J/ by (thermal) gluons

This is next stage J/ suffers after ccbar is bound. Two processes which depends on ccbar binding energy.

_

[Grandchamp+RR ‘01][Bhanot+Peskin ’79]

How to distinguish? How to distinguish? • Suppression vs. Enhancement

– Overall J/ survival• Suppression vs. Enhancementat high energy densities.

– Behavior of pT distribution• Initial state parton scatteringvs. final state charm recombination

– In case of recombination, J/ pT distribution is convolution of charm quark pT distribution.

– Elliptic Flow of J/• In case of recombination, J/ has large v2 (10%) if charm flows.

H. Satz, Hard Probe 2006

9


Centrality dependence

quarkonia production in high energy heavy ion collisions at rhic t. gunji center for nuclear study...

Documents

collisions hot

quark matter

rhic fate of j

gunji title125 slide

gunji outline2 slide

introduction j measurement

gunji center

quarkonia production