Heavy Heavy Flavors at FAIRFlavors at FAIR

EElenalena Bratkovskaya Bratkovskaya

28.06.2008 , WE-Heraeus-Seminar 28.06.2008 , WE-Heraeus-Seminar „„Characterization of the Quark Characterization of the Quark Gluon Plasma with Heavy Quarks‘‘,Gluon Plasma with Heavy Quarks‘‘,

Bad Honnef (Germany)Bad Honnef (Germany)

IntroductionIntroduction

FAIR energiesFAIR energies are well suited to study are well suited to study dense and hot nuclear matterdense and hot nuclear matter – – a phase transition to QGP ,a phase transition to QGP , chiral symmetry restoration, chiral symmetry restoration, in-medium effectsin-medium effects

Observables for CBM:Observables for CBM: Excitation function of Excitation function of

particle yields and ratiosparticle yields and ratios Transverse mass spectraTransverse mass spectra Collective flowCollective flow DileptonsDileptons Open and hidden charm Open and hidden charm Fluctuations and Fluctuations and

correlationscorrelations ......

The way to study:The way to study:Experimental Experimental energy scanenergy scan of of different different observablesobservables in order to in order to find an find an ‚anomalous‘‚anomalous‘ behaviour in behaviour in comparison with comparison with theorytheory

Microscopic transport models Microscopic transport models provide a unique dynamical provide a unique dynamical description of nonequilibrium effects in heavy-ion collisions description of nonequilibrium effects in heavy-ion collisions

HSDHSD – – HHadron-adron-SString-tring-DDynamics transport approachynamics transport approach

•for each particle species for each particle species ii ( (i i = = NN, , RR, , YY, , , , , K, …) the phase-space density , K, …) the phase-space density ffi i followsfollows the the transport equations transport equations

with collision termswith collision terms IIcoll coll describing:describing: elastic and inelastic elastic and inelastic hadronic reactions: hadronic reactions:

baryon-baryon, meson-baryon, meson-mesonbaryon-baryon, meson-baryon, meson-meson formation and decay of formation and decay of baryonic and mesonicbaryonic and mesonic resonancesresonances stringstring formation and decay formation and decay ((for inclusive particle production:for inclusive particle production:

BB BB X , mB X , mB X, X =many particles)X, X =many particles)

• implementation of implementation of detailed balance detailed balance on the level of 1on the level of 122

and 2and 22 reactions (+ 22 reactions (+ 2n n multi-particle reactionsmulti-particle reactions in HSD) in HSD)

•off-shell dynamicsoff-shell dynamics for short-lived states for short-lived states

Basic concept of HSD Basic concept of HSD

),...,f,f(fI,t)p,r(fHHt M21colliprrp

BB BB B´B´, BB B´B´, BB B´BB´B´m´m

mB mB m´B´, mB m´B´, mB B´B´Baryons: Baryons:

B=(p, n, B=(p, n, , ,

N(1440), N(1535), ...)N(1440), N(1535), ...)

Mesons: Mesons:

m=(m=(, , , ,

• very good description of particle production invery good description of particle production in pp, pA reactions pp, pA reactions

• unique description of nuclear dynamicsunique description of nuclear dynamics fromfrom low low (~100 MeV)(~100 MeV) to to ultrarelativistic ultrarelativistic (~20 TeV) energies(~20 TeV) energies

HSD – a microscopic model for heavy-ion reactionsHSD – a microscopic model for heavy-ion reactions

HSDHSD1999 predictions1999 predictions

AGS NA49 BRAHMS

10-1 100 101 102 103 10410-6

10-4

10-2

100

102

104

AGS SPS RHIC HSD ' 99

__

D(c)

J/D(c)

KK+

+

Mul

tipl

icit

y

Au+Au (central)

Energy [A GeV]

Open and hidden charmOpen and hidden charm

Hidden charm: J/Hidden charm: J/ , , ‘: ‘: Anomalous J/Anomalous J/ suppression in A+A suppression in A+A (NA38/NA50/NA60)(NA38/NA50/NA60)

Heavy flavor sectorHeavy flavor sector reflects the early dynamics since reflects the early dynamics since heavy hadrons can heavy hadrons can onlyonly be formed in the very early be formed in the very early phasephase of heavy-ion collisions at FAIR/SPS! of heavy-ion collisions at FAIR/SPS!

J/ ‚normal‘ absorption by nucleons

(Glauber model) ||

Experimental observation:Experimental observation:extra suppression in A+A collisions; increasing with centrality

Quarkonium dissociation temperatures:Quarkonium dissociation temperatures:

I.-II. Scenarios for charmonium suppression in A+AI.-II. Scenarios for charmonium suppression in A+AI.-II. Scenarios for charmonium suppression in A+AI.-II. Scenarios for charmonium suppression in A+A

• I. QGP threshold meltingI. QGP threshold melting[Satz et al’03]

Digal, Fortunato, Satzhep-ph/0310354

Dissociation energy densityDissociation energy densityd d ~ ~ 2(T2(Tdd/T/Tcc))44

0 20 40 60 80 100 120 1400

10

20

30

40

50

NA50 (2000):anal. Aanal. Banal. C

HSD UrQMD

B(

J/)

/(D

Y)| 2.

9-4.

5

Pb+Pb, 160 A GeV

ET [GeV]

J/J/C C meltingmelting

• II. Comover absorptionII. Comover absorption[Gavin & Vogt, Capella et al.`97]:

charmonium absorption by low charmonium absorption by low energy inelastic scattering with energy inelastic scattering with ‚comoving‘ mesons ‚comoving‘ mesons (m=(m= J/J/+m +m D+Dbar D+Dbar

‘‘+m +m D+Dbar D+Dbar

CC+m +m D+Dbar D+Dbar

Charm and Charmonium production and absorption in HSDCharm and Charmonium production and absorption in HSDCharm and Charmonium production and absorption in HSDCharm and Charmonium production and absorption in HSD

Coupled channel problem:Coupled channel problem:J/J/

expexp = = J/J/ + + BB((cc->J/->J/)) cc + + BB((‘‘--

>J/>J/) ) ‘‘

• Charmonium =Charmonium = hard probe hard probe => binary scaling!=> binary scaling!

• ProductionProduction(J/(J/) ) and ((‘ )‘ ) in N+N and in N+N and +N +N collsions:collsions: parametrization of the available exp. parametrization of the available exp. datadata

• Charmonia-baryon dissociation cross Charmonia-baryon dissociation cross sectionssections can be fixed from can be fixed from p+Ap+A data: data:

cc Bcc B ==J/J/ B B== B B= 4.18 mb,= 4.18 mb, ‘‘ B B = 7.6 mb= 7.6 mb

(adopting a Glauber fit from NA50)(adopting a Glauber fit from NA50)

JJ//((cc,,‘)‘) + + BB --> --> D+Dbar D+Dbar

+X+X

10 10010-1

100

101

102

103

104

105

106

10 100

10-1

100

101

102

103

104

105

106

107

D+Dbar +N

J/

/

all xF

N(s

) [

nb]

s1/2 [GeV]

PHENIX

PHENIX

STAR

J/

/

p+N

all xF

D+Dbar

pN(s

) [

nb]

4.0 4.5 5.0 5.5100

101

s1/2 [GeV]

D*+Dbar*

D+Dbar*, D*+Dbar

D+Dbar

[m

b]

II. Modelling of the comover scenario in HSDII. Modelling of the comover scenario in HSD

4.0 4.5 5.0 5.510

-1

100

101

J/+K*

J/+K

J/+

J/+

[m

b]

s1/2

[GeV]

• Phase-space model for Phase-space model for charmonium + meson dissociation:charmonium + meson dissociation:

PRC 67 (2003) 054903PRC 67 (2003) 054903

2.2. JJ// recombinationrecombination cross sections cross sections by D+Dbarby D+Dbar annihilation:annihilation:

D+DbarD+Dbar -> -> JJ//((cc,,‘)‘) + + meson meson ((, , K , K*)K , K*) areare determined bydetermined by detailed balance!detailed balance!

20

2

Ψ

2χ

2J/Ψ

'C

6

432i

43214isospin4321

|M||M||M||M|

ΨJ/Ψ,χi

s

mm|M|

s

EEEE2gsσ

'C

,

constant matrix constant matrix elementelement

1.1. Charmonia Charmonia dissociationdissociation cross sections with cross sections with formedformed ,,KK andand K*K* mesonsmesons

JJ//((cc,,‘)‘) + + meson meson ((, , K , K*)K , K*) D+DbarD+Dbar

Note:Note: comover dissociation as well as DDbar comover dissociation as well as DDbar recombination can occure only if the recombination can occure only if the local energy local energy densitydensity at the collision point at the collision point < 1GeV/fm< 1GeV/fm33

5 10 15 20

10-8

10-7

10-6

10-5

10-4

10-3

time [fm/c]

J/+m->D+Dbar D+Dbar->J/+m

Pb+Pb, s1/2=17.3 GeV, central

dN/d

t

At SPS recreation of J/ by D+Dbar annihilation is negligible

5 10 15 20

10-4

10-3

10-2

10-1

time [fm/c]

J/+m->D+Dbar D+Dbar->J/+m

Au+Au, s1/2=200 GeV, central

dN/d

t

but at RHIC recreation of J/ by D+Dbar annihilation is strong!

(II.) Charmonium recombination by D-Dbar annihilation(II.) Charmonium recombination by D-Dbar annihilation

NNDDDD~16~16

PRC 67 (2003) 054903PRC 67 (2003) 054903

I. Modelling of the QGP melting scenario in HSDI. Modelling of the QGP melting scenario in HSDI. Modelling of the QGP melting scenario in HSDI. Modelling of the QGP melting scenario in HSD

Olena Linnyk et al., Olena Linnyk et al., nucl-th/0612049, NPA 786 (2007) 183; nucl-th/0612049, NPA 786 (2007) 183; arXiv:0801.4282, NPA 807 (2008) 79 arXiv:0801.4282, NPA 807 (2008) 79

Threshold energy densities:Threshold energy densities:

JJ melting: melting: (J(J )=16 GeV/fm)=16 GeV/fm33

cc melting: melting:((c c ) =2 GeV/fm) =2 GeV/fm33

‚‚melting:melting:(( ‚‚) =2 GeV/fm) =2 GeV/fm33

0

5

10

15

1

2

3

4

5

-10-5

05

10

Pb+Pb, 160 A GeVb=1 fm

(0,0

,z)

[GeV

/fm

3]

Energy densityEnergy density (x=0,y=0,z;t) from HSD(x=0,y=0,z;t) from HSDfor Pb+Pb collisions at for Pb+Pb collisions at 160 A GeV160 A GeV

Energy densityEnergy density (x=0,y=0,z;t) from HSD(x=0,y=0,z;t) from HSDfor Au+Au collisions at for Au+Au collisions at 21300 A GeV21300 A GeV

(I.) ‚Local‘ energy density(I.) ‚Local‘ energy density versus Bjorken energy density versus Bjorken energy density BjBj(I.) ‚Local‘ energy density(I.) ‚Local‘ energy density versus Bjorken energy density versus Bjorken energy density BjBj

• transient time for central Au+Au at 200 GeV: transient time for central Au+Au at 200 GeV: ttr r ~ 2R~ 2RAA//cmcm ~ ~ 0.13 fm/c0.13 fm/c

• c-cbar formation time: c-cbar formation time: CC ~ 1/M~ 1/MT T ~ 1/4GeV ~ 0.05 fm/c ~ 1/4GeV ~ 0.05 fm/c < < ttrr

• c-cbar pairs are produced in the c-cbar pairs are produced in the initial hard NNinitial hard NN collisions in time period collisions in time period ttr r

0 100 200 300 4000

1

2

3

4

5

0 100 200 300 4000

1

2

3

4

5

6

7

PHENIX HSD

Au+Au, 200 GeV

dET/d/

0.5N

part [

GeV

]

Npart

PHENIX HSD

Au+Au, 200 GeV

B

j* [

GeV

/fm

2 /c]

Npart

dy

dE

A

1

τ

1ε T

Bj

• Bjorken energy density:Bjorken energy density:

JJ

cc

‚‚

• at RHICat RHIC BjBj ~ 5 GeV/fm~ 5 GeV/fm22/c/c

AAis the nuclei transverse overlap areais the nuclei transverse overlap area is the formation time of the mediumis the formation time of the medium

‚‚Local‘ energy densityLocal‘ energy densityduring during

transient time transient time ttrr GeV/fmGeV/fm22/c] / [0.13 fm/c]/c] / [0.13 fm/c] ~ 30 GeV/fm~ 30 GeV/fm33

accounting accounting CC : :~ 28 GeV/fm~ 28 GeV/fm33

HSD reproduces PHENIX data for Bjorken energy density very wellHSD reproduces PHENIX data for Bjorken energy density very well HSD results are consistent with simple estimates for the energy density HSD results are consistent with simple estimates for the energy density

J/J/and and ´ suppression in In+In and Pb+Pb at SPS: ´ suppression in In+In and Pb+Pb at SPS: (II.) Comover absorption (+ recombination by D-Dbar (II.) Comover absorption (+ recombination by D-Dbar

annihilation)annihilation)

J/J/and and ´ suppression in In+In and Pb+Pb at SPS: ´ suppression in In+In and Pb+Pb at SPS: (II.) Comover absorption (+ recombination by D-Dbar (II.) Comover absorption (+ recombination by D-Dbar

annihilation)annihilation)

• Exp. data (NA50/NA60) for Exp. data (NA50/NA60) for J/J/and and

´ suppression´ suppression for Pb+Pb and for Pb+Pb and In+In at 160 A GeV are consistent In+In at 160 A GeV are consistent with the with the comover absorption model comover absorption model for the same set of parameters!for the same set of parameters!

0 25 50 75 100 125 150

0 50 100 150 2000

10

20

30

40

0 100 200 300 400

HSD

NA50 1997 NA50 1998-2000 Baryon absorption Comover absorption

ET [GeV]

0 50 100 150 2000.000

0.005

0.010

0.015

HSD

Baryon absorption Comover absorption

B

(')

' /

B

(J/

) J/

Npart

HSD

In+In, 158 A GeV

B(

J/)

/(D

Y)| 2.

9-4.

5

Npart

NA60 2005 Glauber model Baryon absoprtion Comover absorption .

HSD

Pb+Pb, 158 A GeV

Npart

NA50 2004 Glauber model Baryon absorption Comover absorption

[Olena Linnyk et al., [Olena Linnyk et al., nucl-th/0612049, NPA 786 (2007) 183 ]nucl-th/0612049, NPA 786 (2007) 183 ]

0 50 100 150 200 250 300 350 4000.4

0.6

0.8

1.0

1.2

NA60, In+In, 158 A GeV (2007)HSD

NA60, In+In, 158 A GeV Comover absorption NA50, Pb+Pb, 158 A GeV Comover absorption

((J

/)/(

DY

)) /

((J

/)/(

DY

))G

laub

er

Npart

J/J/and and ´ suppression in In+In and Pb+Pb at SPS: ´ suppression in In+In and Pb+Pb at SPS: (I.)(I.) QGP threshold melting scenarioQGP threshold melting scenario

J/J/and and ´ suppression in In+In and Pb+Pb at SPS: ´ suppression in In+In and Pb+Pb at SPS: (I.)(I.) QGP threshold melting scenarioQGP threshold melting scenario

• J/J/ suppression is qualitatively suppression is qualitatively ddescribed,escribed, butbut QGP threshold melting scenario showsQGP threshold melting scenario shows

a too strong a too strong ‚‚ absorption, absorption, whichwhich contradicts the NA50 data! contradicts the NA50 data!

0 25 50 75 100 125 150

0 50 100 150 2000

10

20

30

40

0 100 200 300 400

HSD

NA50 1997 NA50 1998-2000 QGP threshold melting

J/=16, c

=2, '=2 GeV/fm3

ET [GeV]

0 50 100 150 2000.000

0.005

0.010

0.015

HSD

QGP threshold melting

J/=16, c

=2, '=2 GeV/fm3

B

(')

' /

B

(J/

) J/

Npart

HSD

In+In, 158 A GeV

B(

J/

)/(

DY

)| 2.9-

4.5

Npart

NA60 2005 QGP threshold melting

J/=16, c

=2, '=2 GeV/fm3

HSD

Pb+Pb, 158 A GeV

Npart

NA50 2004 QGP threshold melting

J/=16, c

=2, '=2 GeV/fm3

Dissociation energy densityDissociation energy density::(J(J )=16 GeV/fm)=16 GeV/fm33, , ((c c ) =2 GeV/fm) =2 GeV/fm33, , (( ‚‚) =2 GeV/fm) =2 GeV/fm33

[Olena Linnyk et al., [Olena Linnyk et al., nucl-th/0612049, NPA 786 (2007) 183 ]nucl-th/0612049, NPA 786 (2007) 183 ]

0 50 100 150 200 250 300 350 4000.4

0.6

0.8

1.0

1.2

NA60, In+In, 158 A GeV (2007)HSD

NA60, In+In, 158 A GeV QGP threshold melting NA50, Pb+Pb, 158 A GeV QGP threshold melting

((J

/)/(

DY

)) /

((J

/)/(

DY

))G

laub

er

Npart

0.0

0.5

1.0 PHENIX, |y|<0.35 PHENIX, 1.2<|y|<2.2

Au+Au, s1/2=200 GeV,comover absorption

HSD |y|<0.35 1.2<|y|<2.2

RA

A(J

/)

0 100 200 300 400

0.000

0.005

0.010

0.015

D+Dbar J/ +m

B

(')

'

/ B

(J/

) J/

Npart

J/J/and and ´ suppression in Au+Au at RHIC: ´ suppression in Au+Au at RHIC: (II.) Comover absorption (+ recombination by D-Dbar annihilation) (II.) Comover absorption (+ recombination by D-Dbar annihilation)

In the comover scenario the In the comover scenario the J/J/suppression at suppression at mid-rapiditymid-rapidity is is strongerstronger thanthan at at forwardforward rapidity, rapidity, unlike unlike the data!the data!

Pure comover scenario is ruled out by Pure comover scenario is ruled out by PHENIX dataPHENIX data!!

-3 -2 -1 0 1 2 3

10-4-3 -2 -1 0 1 2 3

10-4

central, 0-20%

B

dN

(J/

)/dy

-3 -2 -1 0 1 2 310-5

10-4

comover PHENIX

Au+Au, s1/2=200 GeV

HSD

semi-central, 20-40%

semi-peripheral, 40-60%

B

dN

(J/

)/dy

y-3 -2 -1 0 1 2 3

10-6

10-5

y

peripheral, 60-90%

Olena Linnyk et al., Olena Linnyk et al., nucl-th/0612049, NPA 786 (2007) 183; nucl-th/0612049, NPA 786 (2007) 183; arXiv:0801.4282, NPA 807 (2008) 79 arXiv:0801.4282, NPA 807 (2008) 79

0.0

0.5

1.0

PHENIX, |y|<0.35 PHENIX, 1.2<|y|<2.2

HSD |y|<0.35 1.2<|y|<2.2

RA

A(J

/)

Au+Au, s1/2=200 GeV, QGP threshold scenario

+ recombinationD+Dbar J/ +m

without recombination

0 100 200 300

0.000

0.005

0.010

0.015

B

(')

'

/ B

(J/

) J/

Npart

0 100 200 300 400

Npart

QGP threshold melting scenario is ruled out by QGP threshold melting scenario is ruled out by PHENIX dataPHENIX data!!

J/J/and and ´ suppression in Au+Au at RHIC: ´ suppression in Au+Au at RHIC: (I.)(I.) QGP threshold melting scenarioQGP threshold melting scenario

Satz’s model:Satz’s model: complete dissociation of complete dissociation of initial initial J/J/and and ´́ due to the huge local due to the huge local energy densities ! energy densities !

Charmonia Charmonia recombinationrecombination by D-Dbar annihilationby D-Dbar annihilation is important, however, it can not generate enough is important, however, it can not generate enough charmonia, especially for peripheral collisions! charmonia, especially for peripheral collisions!

[Olena Linnyk et al.,[Olena Linnyk et al., arXiv:0705.4443, arXiv:0705.4443, PRC 76 (2007) 041901 PRC 76 (2007) 041901 ]]

Summary (I.-II. )Summary (I.-II. )Summary (I.-II. )Summary (I.-II. )

I. QGP ‚threshold melting‘I. QGP ‚threshold melting‘

versus experimental dataversus experimental data

SPS SPS RHICRHIC

J/J/survivalsurvival:: ++

‚‚/ J// J/ratio :ratio : ??

II. Comover absorption II. Comover absorption

(+ recombination by D-Dbar (+ recombination by D-Dbar annihilation)annihilation)

versus experimental dataversus experimental data

SPS SPS RHICRHIC

J/J/survivalsurvival:: + +

‚‚/ J// J/ratio :ratio :

??ComoverComover absorption absorption and threshold melting and threshold melting scenarios are ruled out scenarios are ruled out by experimentalby experimental data data

evidence for non-hadronic interaction ?!evidence for non-hadronic interaction ?!

III. Scenarios for charmonium suppression in A+AIII. Scenarios for charmonium suppression in A+AIII. Scenarios for charmonium suppression in A+AIII. Scenarios for charmonium suppression in A+A

• III. Pre-hadronic interaction scenario :III. Pre-hadronic interaction scenario : early interactionsearly interactions of charmonium (ccbar) and D-mesons of charmonium (ccbar) and D-mesons with unformed with unformed (i.e. under formation time t = (i.e. under formation time t = F F , , FF ~0.8 fm/c in the hadron rest frame) ~0.8 fm/c in the hadron rest frame) baryons and mesons baryons and mesons - pre-hadrons- pre-hadrons + + comover absorption with recombination by D-Dbar annihilationcomover absorption with recombination by D-Dbar annihilation

Dissociation cross sections of charmonium by pre-hadrons:Dissociation cross sections of charmonium by pre-hadrons: disdis

cc pre-Baryoncc pre-Baryon = = 5.8 mb,5.8 mb,

disdiscc pre-mesoncc pre-meson = = 2/32/3 disdis

cc pre-Baryoncc pre-Baryon

Elastic cross sections with prehadrons:Elastic cross sections with prehadrons: Charmonium - prehadrons:Charmonium - prehadrons: D-meson - prehadrons:D-meson - prehadrons:

elelcc pre-Baryoncc pre-Baryon = = 1.9 mb,1.9 mb, elel

D pre-BaryonD pre-Baryon = = 3.9 mb, 3.9 mb,

elelcc pre-mesoncc pre-meson = 2/3 = 2/3 elel

cc pre-Baryoncc pre-Baryon elelD pre-mesonD pre-meson = = 2/32/3 elel

cc pre-Baryoncc pre-Baryon

Pre-hadronic Pre-hadronic interaction scenariointeraction scenario only ‚simulates‘ the interactions in the QGP only ‚simulates‘ the interactions in the QGP in the Hadron-String model without in the Hadron-String model without (!)(!) explicit partonic interactions and phase explicit partonic interactions and phase transition transition => NOT (yet!) a consistent description !=> NOT (yet!) a consistent description ! => PHSD=> PHSD

Fitted to PHENIX data

Fitted to PHENIX data

J/J/and and ´ suppression in Au+Au at RHIC: ´ suppression in Au+Au at RHIC: (III.) Pre-hadronic interaction scenario(III.) Pre-hadronic interaction scenario

In the prehadronic interaction scenario the J/In the prehadronic interaction scenario the J/rapidityrapidity distributiondistribution has the right has the right shape shape like the PHENIX data! => like the PHENIX data! => can can describe the describe the RHIC RHIC datadata at at s s1/21/2=200 GeV =200 GeV for Au+Aufor Au+Au at at mid- and forward-rapidities simultaneouslymid- and forward-rapidities simultaneously..

Olena Linnyk et al., Olena Linnyk et al., arXiv:0801.4282, NPA 807 (2008) 79 arXiv:0801.4282, NPA 807 (2008) 79

-3 -2 -1 0 1 2 3

10-4-3 -2 -1 0 1 2 3

10-4

central, 0-20%

B

dN

(J/

)/dy

-3 -2 -1 0 1 2 310-5

10-4

comover prehadron interactions PHENIX

Au+Au, s1/2=200 GeV

HSD

semi-central, 20-40%

semi-peripheral, 40-60%

B

dN

(J/

)/dy

y-3 -2 -1 0 1 2 3

10-6

10-5

y

peripheral, 60-90%0 100 200 300 4000.0

0.5

1.0

Au+Au, s1/2=200 GeVPrehadron interactions

PHENIX |y|<0.35 1.2<|y|<2.2

Npart

HSD |y|<0.35 1.2<|y|<2.2

RA

A(J

/)

J/J/and and ´ suppression in Au+Au at RHIC´ suppression in Au+Au at RHIC

PHENIX dataPHENIX data: : evidence for non-hadronic interactions of charm evidence for non-hadronic interactions of charm degrees of freedom !degrees of freedom !

Olena Linnyk et al., Olena Linnyk et al., arXiv:0801.4282, NPA 807 (2008) 79 arXiv:0801.4282, NPA 807 (2008) 79

0 50 100 150 200 250 300 350 4000.0

0.5

1.0

1.5

2.0

2.5

Au+Au, s1/2=200 GeV

HSD

RA

A(f

orw

ard

y)

/ RA

A(m

id-y

)

Npart

PHENIX comover absorption threshold melting prehadron interactions

•Comover Comover reactions in the hadronic phase give almost a constant suppression; reactions in the hadronic phase give almost a constant suppression; pre-hadronic reactions lead to a larger recreation of charmonia with Epre-hadronic reactions lead to a larger recreation of charmonia with Ebeambeam

•The J/The J/ melting scenariomelting scenario with with charmonia charmonia recombination by DDbar recombination by DDbar annihilationannihilation shows a shows a maximum suppressionmaximum suppression at E at Ebeambeam = 1 A TeV; = 1 A TeV;

exp. data ?exp. data ?

J/J/excitation functionexcitation function

100 1000 100000.0

0.2

0.4

0.6

0.8

1.0

Central

S

(J/

)

Ebeam

, A GeV

Comover QGP threshold

100 1000 100000.0

0.2

0.4

0.6

0.8

1.0

Minimum bias

HSD

J/ excitation function

S(J

/)

Ebeam

, A GeV

[Olena Linnyk et al., [Olena Linnyk et al., arXiv:0801.4282, NPA 807 (2008) 79 arXiv:0801.4282, NPA 807 (2008) 79 ]]

FAIRFAIR

FAIRFAIR

100 1000 100000.000

0.004

0.008

0.012

Central

B

( ')

'

/ B

(J

/) J/

Ebeam

, A GeV

Comover QGP threshold

100 1000 100000.000

0.004

0.008

0.012

B

( ')

'

/ B

(J

/) J/

Minimum bias

HSD

' to J/ ratio

Ebeam

, A GeV

´ suppression´ suppression provides independent information provides independent information on absorption versus recreation mechanisms ! on absorption versus recreation mechanisms !

´ excitation function´ excitation function

[Olena Linnyk et al., [Olena Linnyk et al., arXiv:0705.4443, PRC 76 (2007) 041901 arXiv:0705.4443, PRC 76 (2007) 041901 ]]

FAIRFAIR

FAIRFAIR

[Olena Linnyk et al., [Olena Linnyk et al., arXiv:0801.4282, NPA 807 (2008) 79 arXiv:0801.4282, NPA 807 (2008) 79 ]]

HSD predictions for J/HSD predictions for J/and and ´ suppression in Au+Au at CBM energies´ suppression in Au+Au at CBM energiesHSD predictions for J/HSD predictions for J/and and ´ suppression in Au+Au at CBM energies´ suppression in Au+Au at CBM energies

Different scenarios can be distinguished already Different scenarios can be distinguished already at FAIR energies:at FAIR energies:

´ over J/´ over J/ratioratio is lower in the comover is lower in the comover absorption model since the average comover absorption model since the average comover density decreases only moderately with lower density decreases only moderately with lower bombarding energy whereas the energy bombarding energy whereas the energy density decreases rapidlydensity decreases rapidly

0 50 100 150 200 250 300 350 4000.0

0.2

0.4

0.6

0.8

1.0

HSD

S(J/)

Npart

Baryon absorption Comover absorption QGP threshold melting

J/=16,

c

=2, '=6.55 GeV/fm3

0 50 100 150 200 250 300 350 4000.000

0.002

0.004

0.006

Au+Au, 25 A GeV

HSD

Comover absorption QGP threshold melting

J/=16,

c

=2, '=6.55 GeV/fm3

QGP threshold melting

J/=16,

c

=2, '=2 GeV/fm3

B

(')

' /

B

(J/

) J/

Npart

0 50 100 150 200 250 300 350 4000.0

0.2

0.4

0.6

0.8

1.0

Comover absorption

Pb+Pb

HSD

S

Npart

Energy A GeV 20 30 40 160

[Olena Linnyk et al., [Olena Linnyk et al., arXiv:0705.4443, PRC 76 (2007) 041901 arXiv:0705.4443, PRC 76 (2007) 041901 ]]

HSD: vHSD: v22 of D+Dbar and J/ of D+Dbar and J/ from Au+Au versus p from Au+Au versus pTT and y at RHIC and y at RHIC HSD: vHSD: v22 of D+Dbar and J/ of D+Dbar and J/ from Au+Au versus p from Au+Au versus pTT and y at RHIC and y at RHIC

• Pre-hadronic interactionsPre-hadronic interactions lead to an lead to an increase increase of the of the elliptic flow v elliptic flow v2 2

• The The pre-hadronic interaction scenario is pre-hadronic interaction scenario is ~consistent~consistent with the with the preliminary PHENIX data on the D-mesons vpreliminary PHENIX data on the D-mesons v22

=> strong initial flow of non-hadronic nature! => strong initial flow of non-hadronic nature!

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0-0.3

-0.2

-0.1

0.0

0.1

0.2

0.3

PHENIX preliminary |y|<0.35, 20%-60% centrality

J/, Au+Au, s1/2=200 GeV, |y|<1min bias, HSD

comover prehadron interactions

v 2 (p

T)

pT [GeV/c]

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5-0.05

0.00

0.05

0.10

0.15Au+Au, s1/2=200 GeV

HSD, D-mesons comover(+recombination) + prehadron interactions PHENIX PHENIX, QM'08

v 2 (p T

)

pT [GeV/c]

[Olena Linnyk et al., [Olena Linnyk et al., arXiv:0801.4282, NPA 807 (2008) 79 arXiv:0801.4282, NPA 807 (2008) 79 ]]

HSD predictions for CBM - elliptic flow at 25 A GeVHSD predictions for CBM - elliptic flow at 25 A GeV

Challenge for CBM!Challenge for CBM!

0.0 0.5 1.0 1.5 2.0-0.05

0.00

0.05

0.10

0.15

0.20

v 2

Au+Au, 25 A GeV b=7 fm, |y|<1

charged hadrons D+Dbar

HSD

pT [GeV/c]

•HSD:HSD: D-mesons and D-mesons and J/J/follow the charged particle follow the charged particle

flow flow small vsmall v2 2

Possible observation at CBM:Possible observation at CBM: strong initial flow strong initial flow of D-mesons of D-mesons and J/and J/ due to due to partonic partonic interactions!interactions!

• J/J/ probes early stages probes early stages of fireball and HSD is the tool to model it. of fireball and HSD is the tool to model it.

• Comover absorption and threshold meltingComover absorption and threshold melting:: both reproduce J/ both reproduce J/ survival in Pb+Pb as well as in In+Insurvival in Pb+Pb as well as in In+In at at SPSSPS, while , while ´́/J//J/datadata appear appear to be in conflict with the ‚melting scenario‘to be in conflict with the ‚melting scenario‘..

• Comover absorption and threshold meltingComover absorption and threshold melting fail to fail to describe the describe the RHIC RHIC datadata at at s s1/21/2=200 GeV for Au+Au=200 GeV for Au+Au at mid- and forward-rapidities at mid- and forward-rapidities simultaneouslysimultaneously

• Prehadronic interaction scenarioPrehadronic interaction scenario can can describe the describe the RHIC RHIC datadata at at ss1/21/2=200 GeV for Au+Au=200 GeV for Au+Au at at mid- and forward-rapidities simultaneouslymid- and forward-rapidities simultaneously

• STAR data on STAR data on vv22 of of high phigh pTT charged hadrons and charm D mesons are charged hadrons and charm D mesons are not reproduced in the hadron-string picture not reproduced in the hadron-string picture => evidence for a plasma => evidence for a plasma pressure ?!pressure ?!

SummarySummary

• FAIRFAIR is anis an excellent facilityexcellent facility toto study the properties of the sQGP study the properties of the sQGP (strongly interacting ‚color liquid‘) (strongly interacting ‚color liquid‘) as well as hadronic matter as well as hadronic matter

Outlook

• Transport theory Transport theory is theis the general basisgeneral basis for an for an understanding of nuclear understanding of nuclear dynamics on a microscopic leveldynamics on a microscopic level

UrQMD: U+U, 25 A GeVUrQMD: U+U, 25 A GeV

ThanksThanks toto

Olena Linnyk Olena Linnyk

Wolfgang Cassing Wolfgang Cassing

Horst StöckerHorst Stöcker

- More slides -- More slides -

D+Dbar transverse pD+Dbar transverse pTT spectra from Au+Au – HSD predictions spectra from Au+Au – HSD predictions

• InteractionsInteractions (inelastic (inelastic and elastic) of D/Dbar and elastic) of D/Dbar and J/and J/withwith hadronic hadronic mediummedium change the change the shape of the initial shape of the initial spectra (i.e. at the spectra (i.e. at the production point).production point).

However, a full However, a full thermalizationthermalization of of charm (charmonium) charm (charmonium) ppTT spectra is spectra is NOTNOT

achieved achieved in the hadron-in the hadron-string model string model

[E. B., W. Cassing, H. Stöcker, N. Xu, PRC 71 (2005) 044901][E. B., W. Cassing, H. Stöcker, N. Xu, PRC 71 (2005) 044901]

0.0

0.5

1.0

1.5

2.0

0 1 2 3 4 5 60.0

0.5

1.0

1.5

0 1 2 3 4 5 6 7

Au+Au, s1/2=200 GeV, |y|<1

(1/p

TdN

fina

l /dp T

) / (

1/p T

dNpr

oduc

tion

/dp T

)

D+Dbar J/

b=5 fm

b=7 fm

b=1 fm

pT [GeV/c]

b=12 fm

pT [GeV/c]

(II.) Comover absorption (+ recombination by D-Dbar annihilation)(II.) Comover absorption (+ recombination by D-Dbar annihilation)

-2 -1 0 1 20.0

0.5

1.0

s1/2=200 GeV

RdA

y

PHENIX HSD

Supression in cold nuclear matter

Charmonium is absorbed by scattering on baryons

[OL et al., arXiv:0801.4282 ]