1 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

Kollektive Eigenschaftenin Kern-Kern Kollisionen

bei hohen Energien

Kai Schweda, Physikalisches Institut/ GSI Darmstadt

2 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

Quantum Chromodynamics

1) Quantum Chromodynamics (QCD) is the established theory of strongly interacting matter.

2) Gluons hold quarks together to from hadrons:

3) Gluons and quarks, or partons, typically exist in a color singlet state: confinement.

baryonmeson

3 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

http://www.lbl.gov/Publications/Nobel/

COBE: Discovery `baby photo’ of the universeRHIC: Live history of the universe

LHC RHIC COBE

George SmootJohn Mather

10 –6 sec 10 –4 sec 3 min 15 Mil Jahre

Quark-GluonPlasma Nukleonen Kerne Atome Heute

Natur

Experiment

Urknall

4 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

Quark Gluon Plasma

Source: Michael Turner, National Geographic (1996)

Quark Gluon Plasma:

(a) Deconfined and

(b) thermalized state of quarks and gluons

Study partonic EOS at RHIC and LHC(?) Probe thermalization using heavy-quarks

5 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

Peripheral Event

STARSTAR

Au + Au Collisions at RHICAu + Au Collisions at RHIC

(real-time Level 3)

6 Symposium, Heidelberg, 12 Dec 2006 Kai SchwedaSTARSTAR

Mid-Central Event

Au + Au Collisions at RHICAu + Au Collisions at RHIC

(real-time Level 3)

7 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

Au + Au Collisions at RHICAu + Au Collisions at RHIC

STARSTAR

Central Event

(real-time Level 3)

8 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

Pressure, Flow, …Pressure, Flow, …

pdVdUd Thermodynamic identity

– entropy p – pressureU – energy V – volume= kBT, thermal energy per dof

In A+A collisions, interactions among constituentsand density distribution lead to: pressure gradient collective flow

number of degrees of freedom (dof) Equation of State (EOS) cumulative – partonic + hadronic

9 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

Protons From RHIC

Mor

e ce

ntra

l col

lisio

ns

1) In central collisions, spectrum becomes more concave

collective flow !2) Flow velocity <> = 0.60 ± 0.05 in most central collisions

Anisotropy Parameter v2

y

x

py

px

coordinate-space-anisotropy momentum-space-anisotropy

y 2 x 2y 2 x 2

v2 cos2 , tan 1(py

px

)

Initial/final conditions, EoS, degrees of freedom

11 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

v2 at Low Momentum

P. H

uo

vi ne

n, p

r ivate

com

mu

nica

t i on

s, 20

04

- Mass hierarchy collective flow !- Hydro-dynamical model : acces to equation of state !

12 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

-meson Flow: Partonic Flow

-mesons:

- little hadronic interactions

- strong collective flow

- formed via coalescence of

thermal s-quarks

Collectivity at

quark level !

STAR Preliminary: SQM06, S. Blyth

Hwa and Yang, nucl-th/0602024; Chen et al., PRC73 (2006) 044903

13 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

Collectivity, Deconfinement at RHIC

- v2 of light hadrons and multi-strange hadrons - scaling by the number of quarks

At RHIC: number-of-constituent

quark scaling

De-confinement

PHENIX: PRL91, 182301(03) STAR: PRL92, 052302(04), 95, 122301(05) nucl-ex/0405022, QM05

S. Voloshin, NPA715, 379(03)Models: Greco et al, PRC68, 034904(03)Chen, Ko, nucl-th/0602025Nonaka et al. PLB583, 73(04)X. Dong, et al., Phys. Lett. B597, 328(04).

i ii

14 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

EoS Parameters at RHIC

In central Au+Au collisions at RHIC - partonic freeze-out:

*Tpfo = 165 ± 10 MeV weak centrality dependence

vpfo ≥ 0.2 (c)

- hadronic freeze-out:*Tfo = 100 ± 5 (MeV) strong centrality

dependence

vfo = 0.6 ± 0.05 (c)

Systematic studies are needed to understand the centrality dependence of the EoS parameters * Thermalization assumed

Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

Quark Masses

1) Higgs mass: electro-weak symmetry breaking. (current quark mass)

2) QCD mass: Chiral symmetry breaking. (constituent quark mass)

Strong interactions do not

affect heavy-quark masses.

Important tool for studying properties of the hot/dense medium at RHIC.

Test pQCD predictions at RHIC and LHC.

Total quark mass (MeV)

16 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

J/Enhancement at LHC Statistical hadronization

strong centrality dependence

of J\ yield at LHC

Need total charm yields !

Measure D0, D±, c

Probe deconfinement

and thermalization

Calculations: P. Braun Munzinger, K. Redlich, and J. Stachel, nucl-th/0304013.

cc

Number of participants

More central collisions

J/: c c

17 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

Pb+Pb

ccc / D :

p+p

c

c c

Multiply Heavy-flavored Hadrons

F. Becattini, Phys. Rev. Lett. 95, 022301 (2005);P. Braun Munzinger, K. Redlich, and J. Stachel, nucl-th/0304013.

Statistical hadronization

- de-confined heavy-quarks

- equilibrated heavy-quarks

Enhancement up to x1000 !

Measure cc, cc, Bc, (ccc)

Need total charm yields

Probe deconfinement and

thermalization @ LHC

Quark Gluon Plasma !

Quarks and gluons hadrons

x1000

18 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

The key point is to idenitfy and measure

Heavy-Flavor CollectivityD0, D, D+

s, +C, J/, B0, B±, , …

19 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

Energie in einer Blei-Blei Kollision

1150 TeV = 0.18 mJ

Faktor 300 höher als in SPS Experimenten

sehr heisser Feuerball!

T = 1000 MeV

Large Hadron Collider

LHC am CERN

20 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

ITS

TPCTRD

ALICE beim LHC

Bis zu 60000 geladene Teilchen

Faktor 25 höher als beim SPS

~ PetaByte (1015) pro Jahr

21 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

22 Symposium, Heidelberg, 12 Dec 2006 Kai Schweda

J/ e+ + e- Reconstruction

J/ e+ + e-

(BR = 6%)

Reconstruct

invariant mass

TRD identifies

electrons

Identify

quarkonia

J/: c c : b b

Ta

ken

fr om

P. S

en

ge

r

1) LHC heavy-flavor program:

2) FAIR / CBM program:

- Study medium properties- pQCD in hot and dense medium - Search for phase boundary.- Chiral symmetry restoration

Start: 2007

Start: ~2012