Big Bang

Roy A. Lacey, Stony Brook University; QM11, Annecy, France 2011

200NNs

p

Big Bang

“The major discoveries in the first five years at

RHIC must be followed by a broad, quantitative

study of the fundamental properties of the quark

gluon plasma …”

The Frontiers of Nuclear Science A Long Range Plan - 2007

T, cs, ˆ, , etc ?q Characterization requires

Quantitative study of the phases of QCD is a central goal of our fieldQuantitative study of the phases of QCD is a central goal of our field


The extraction of transport coefficients is central to the heavy ion programs at RHIC and the LHC

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ηη/s estimates – QM2009/s estimates – QM2009

Remarkable Convergence


4πη/s ~ 1 - 2

Major remaining uncertainty stems from Incomplete

knowledge of the Initial eccentricity

εn – η/s interplay

New constraints required for the initial eccentricity model and η/s

(still 100% uncertainty)

Do higher-order flow harmonics provide such constraints? Implications for decomposition of two-particle correlation functions

Conjectured Lower bound

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The Flow probeThe Flow probe

Odd harmonics ≠ 0Odd harmonics ≠ 0


1

( ) 1 2 cosn nn

f v n

2

0( ) ninin in

ne e f d v e ( )

n , 1, 2,3.., npinv e n

For "lumpy" profile

2 2

2 2

y x

y x

For smooth profile

Odd harmonics = 0Odd harmonics = 0

pairs

1

1 2 cos( )a bn n

n

dNv v n

d

20

3

1 1

~ 5 15

TBj

dE

R dy

GeV

fm

Primary ParametersPrimary Parameters

, , , T,s fc T , , , T,s fc T

s/

P ² Bj

Azimuthal Distribution

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PHENIX MeasurementsPHENIX MeasurementsPHENIX Central Arms (CA) |η’| < 0.35

(particle detection)

RXNRXN

BBC/MPC BBC/MPC

Planes (EP)

Event6 7 8 Planes (EP)

Event6 7 8

∆η’ = 5-7 1

1 2 cos ( )n nn

dNv n

d

n , 1, 2,3..,{ } co sn nv n n

pairs

1

1 2 cos( )a bn n

n

dNv v n

d

Two complimentary analysis methods employed:

Correlate hadrons in central Armswith event plane (RXN, etc)

∆φ correlation function for EPN - EPS

Correlations between sub-event planes (EPN - EPS ) also

studied!

ψn RXN (||=1.0~2.8)

MPC (||=3.1~3.7) BBC (||=3.1~3.9)

Schematic Detector Layout

Sub-event participant plane = ΦN,S

∆φ correlation function for EP - CA

(I)

(II)

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Results: Event planeResults: Event planeCorrelationsCorrelations

Clear 12 correlation well known

Weak 24 correlation well known

Weak 13 correlation Not unexpected

No vis. 23 correlation Fluctuations important

Sub-event correlations give crucial insights on the expected correlations and the role of fluctuations

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Results: vResults: vnn(ψn)

Robust PHENIX measurements performed at 200 GeV(Crosschecked with correlation method)

http://arxiv.org/abs/1105.3928

v4(ψ4) ~ 2v4(ψ2)

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Results: vResults: vnn(∆φ)

Robust measurements performed at 200 GeV(Crosschecked with event-plane method)

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What do we learn from these newWhat do we learn from these newvvnn measurements? measurements?

Roy A. Lacey, Stony Brook University; QM11, Annecy, France 20119 of 17


New constraints for New constraints for εεnn and and ηη/s/s

v3 breaks the ambiguity between CGC vs. Glauber initial conditions and η/s


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Flow is pressure driven

Phys. Rev. Lett. 98, 162301 (2007)

Mesons

Baryons

vv33 PID scaling PID scaling

vv44 scaling scaling


Flow is partonic

vv22 scaling scaling

Flow is partonicFlow is partonic

KET & scaling validated for v3

Partonic flow

/2n

qn

Consistent partonic flow picture for vn

Reminder

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Results: vResults: vnn(∆φ)

v2,3,4 saturates for the range √sNN 39 - 200 GeV

See Xiaoyang Gong’s talk Energy Scan Session – Friday 17:50 – 18:10

on Friday

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Results: Decomposition of two-particle Results: Decomposition of two-particle ∆φ Correlation Functions

Two particle ∆φ correlations for 0.3 < |∆η| < 0.7 show the effects of jet contributions to the correlation function

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Results: Decomposition of two-particle Results: Decomposition of two-particle ∆φ Correlation Functions

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Viscous effects ~ cancel

Acoustic scalingAcoustic scaling http://arxiv.org/abs/1105.3782

Acoustic ScalingAcoustic Scaling

Higher-order harmonics should scale as a power of vHigher-order harmonics should scale as a power of v22

Deformation 2 GR n

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Approx.


Acoustic scalingAcoustic scaling

Viscous Horizon (rrv v )

New constraints from acoustic scalingNew constraints from acoustic scaling Glauber eccentricityGlauber eccentricity 44πηπη/s = 1.4/s = 1.4 rrvv ~ 1.9 fm ~ 1.9 fm Similar estimates for LHCSimilar estimates for LHC

Cancellation of viscous effectsallow constraint for eccentricity

Estimate 4Estimate 4πηπη/s from slope/s from slope(Independent estimat(Independent estimate)e)

{

The viscous horizon (rv) is the length-scale which characterizes the

highest harmonic that survives viscous damping

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Staig & ShuryakarXiv:1008.3139

Higher-order flow harmonics extracted Higher-order flow harmonics extracted by PHENIX! by PHENIX!

summarysummary


Provide new constraints for εn and η/s Further confirm that flow is partonic v2,3,4 saturates for √sNN 39 - 200 GeV Allow a more robust decomposition of Of two-particle ∆φ correlation functions

Show that Flow is acoustic new constraints for:

η/s initial geometry viscous horizon

v

4

r

n

s

Precision extractions underway!

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End

Roy A. Lacey, Stony Brook University; QM11, Annecy, France 2011 18



Npart

0 100 200 300

v 2/ 2

0.0

0.2

0.4

0.6

(a)


Data

Deformation 2 GR n


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Deformation 2 GR n


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Scaling observed for vScaling observed for vnn



Similar scaling For all centrality

/2

2

nn

vv

independent of pT

Viscous effects cancel

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Similar scaling For all centrality

/2

2

nn

vv

independent of pT

Viscous effects cancel

Acoustic scalingAcoustic scalinghttp://arxiv.org/abs/1105.3782

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New constraints for New constraints for εεnn and and ηη/s/s

Good agreement between data and theory for

Glauber with fluctuating initial conditions 4πη/s ~ 1


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Phys.Rev.Lett.105:062301,2010

Flow MeasurementsFlow Measurements

High precision double differential measurements are pervasive!

Roy A. Lacey, Stony Brook University; QM11, Annecy, France 2011 24 of 23


Good agreement between measurements

Precision DataPrecision DataPrecision DataPrecision DataRXNRXN

BBC/MPC BBC/MPC

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Precision DataPrecision DataPrecision DataPrecision Data

Excellent agreement between experiments for √s = 39 -200 GeV!


Preliminary, STAR, PHENIX and E895 data

Precision DataPrecision DataPrecision DataPrecision Data


Excellent agreement between experiments for the excitation function! Crucial for η/s extraction and the critical point search

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Relaxation time limits η/s to small values


Estimates for Estimates for ηη/s/sEstimates for Estimates for ηη/s/s

v2

pT

G. Denicol et al

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Constraints for Constraints for ηη/s/sConstraints for Constraints for ηη/s/s

14

1 2.5 s

Song et al. arXiv:1011.2783

Model uncertainty dominated by ε


Hydrodynamic Model ComparisonHydrodynamic Model Comparison

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PHENIX Preliminary

PHENIX Preliminary

KET & nq scaling validated for v2 as a function of centrality

Flow scales across centralityFlow scales across centralityFlow scales across centralityFlow scales across centrality

PHENIX PreliminaryPHENIX Preliminary

PHENIX Preliminary PHENIX Preliminary


Scaling constrains Scaling constrains ηη/s/sScaling constrains Scaling constrains ηη/s/s

Demir et al

η/s from hadronic phase is very large 10-12x(1/4π)No room for such values!


Partonic flow dominates!Partonic flow dominates!Hadronic contribution cannot be largeHadronic contribution cannot be large

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Big Bang