flow correlations @ rhic: “an abridged phenix view” roy a. lacey (for the phenix...

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Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Flow Correlations @ RHIC:“an abridged PHENIX view”

Roy A. Lacey (for the PHENIX collaboration)Chemistry Dept.

Stony Brook University

AimGive a survey of PHENIX Flow measurementsHighlight several implications What theorist need to know

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Coupling

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Lacey Flow

Correlations

Taranenko

Comparison of v2

Ajitanand P-

violation

Now

Thursday – 5:20 PM

Tuesday – 10:20 AM

2

2 4 11 2 cos 2 φ 2 cos 4 φ 2 sin 2 φφ RP RP RP

T

d N v v adp d

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Why study Flow?

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Flow measurements give accessto the properties of the new state of matter recently discovered at RHIC

Access:

Direct T, cs, η, ζ, etc Indirect constrains dynamics for determination Crucial for Critical End Point (CEP) search

q̂

Flow studies are indispensible

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The Flow Probe

y

x s/

P ² Bj

2 2

2 2

y x

y x

Primary Control Parameters

, , , sT c FrzOut

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3

1 1

~ 5 15

TBj

dER dyGeVfm

Flow provides unparalleled access to the transport properties of the medium

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~ 1.25ˆT

s q

( )

1

~ s sTs

KR

c KR Tc

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

2

~q

Reac

tion

plane

XZ

Y

Hydrodynamic

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How are transport coefficients obtained from flow data?

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

There are known known's There are known unknowns There unknown unknowns D. Rumsfeld

Comparisons to viscous

hydrodynamicscalculation

Hydrodynamically inspired fits to

Data

Issues• Data (method, role of non-

flow?)• pre vs. post hadronic contributions • Species dependence• Extraction procedure• Initial conditions (ε)• Fit constraints• etc

Critical path issues are common to all methodologies

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No evidence for significant η-dependent non-flow contributionsContributions from the ridge estimated to be small as well

A known known - Flow measurements are robust

3.1 3.9BBC

3.1 3.9MPC

1.5 2.8iRXN

1.0 1.5RXNo

1.0 2.8ioRXN

Event planes

PHENIX Preliminary

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Central Arms

RXNRXN

BBC/MPC BBC/MPC

Consistent results for v4 / v2 2

ratio using measurements

with respect to the different event planes

PHENIX Preliminary

Central Arms

RXNRXN

BBC/MPC BBC/MPC

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

A known known – Consistency of higher harmonics

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PHENIX Preliminary

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

A known known – agreement between RHIC measurements

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Taranenko will discuss this in detail!

The results from different methods should Not be used as a measure of systematic error!

EP

Issues: different experimental results results from different methods which data set to use ?

There is good agreement between experiments Consideration of fluctuations important when

comparing different methods

9Roy A. Lacey, Stony Brook University;

CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

A known known – Energy dependence of v2

~ 50% increase from SPS to RHIC.

Apparent saturation above 62.4 GeV λ= 1 ?

RK

PHENIX Preliminary

PHENIX Preliminary

KET & nq (nq2) scaling validated for v2

as a function of centrality

A known known – Flow scales

PHENIX PreliminaryPHENIX Preliminary

PHENIX Preliminary PHENIX Preliminary

10Roy A. Lacey, Stony Brook University;

CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Au+Au at √sNN = 200 GeV

PHENIX Final Run4PHENIX Preliminary Run7

Minimum bias

van Hees et al.

A known known – Charm flows and scales

Strong coupling η/s - estimate

J/(ccbar) v2 still challenged by statistics

11Roy A. Lacey, Stony Brook University;

CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

12 of 23

KET & nq (nq2) scaling validated for v2

(v4)

A known known - universal scaling of harmonic flow at RHIC

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

PHENIX Preliminary

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A known known - flow is partonic

Partonic flow dominates!

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

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

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Sideward's flow depend on particle species

Hadronic flow at lower energies – v1

PRL 85, 940 (2000)PRL 85, 940 (2000)

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Bleicher et al

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NCQ scaling is expected to break at

intermediate pT if pions are mainly from

recombination of TS partons but protons are

mainly from TTS and TSS .

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

A known known – Scaling breaks at high pT

Hwa &Yang arXiv:0801.2183[nucl-th]

A Known Unknown – initial eccentricity

16Roy A. Lacey, Stony Brook University; CATHIE-

TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Geometric fluctuations are very important – be skeptical of any claim that does not include them

eccentricity should be constrained

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What do the fits and model comparisons tell us?

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Romatschke, Romatschke, & Luzum

pions

PHENIX preliminary data

pT (GeV/c)

v2

Calculations suggest small η/s value

Viscosity required for KET scaling Lower Limit ?

Chaudhuri

18Roy A. Lacey, Stony Brook University;

CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Estimates for η/s

Extracted η/s is small

19Roy A. Lacey, Stony Brook University;

CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Estimates for η/s

Teaney

20Roy A. Lacey, Stony Brook University;

CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Estimates for η/s

C. Gombeaud, J.-Y. OllitraultarXiv:0907.4664, arXiv:0910.0392

Ideal hydro.

Ideal hydro. + fluctuation

Ideal hydro. + fluctuation+ incomplete thermalization

Fluctuations are very important

Relaxation time limits η/s to small values

21Roy A. Lacey, Stony Brook University;

CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Estimates for η/s

v2

pT

G. Denicol et al

22Roy A. Lacey, Stony Brook University;

CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Strategyquantify the viscous

corrections to hydrodynamicsvia a simple fitting procedure, to

obtain K as a function of Npart

Knudsen number parameterization

v2/ε

Npart

Ideal hydrodynamics~ ( )s n sTc K R Tc

s

Obtain from fits to data(viscous correction)

Geometry(from model)

Lattice EOS

With viscosity

Obtain from fits to data(viscous correction)

23Roy A. Lacey, Stony Brook University;

CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Calibration of the method

Methodology successfully proofed – very important

~ ( )s n sTc K RT cs

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New constraints for η/s

T also obtained from the fit!

~ ( )s n sTc K R Tcs

Viscous corrections Grow as :

(Teaney)

Lattice EOS

Geometric

Not an intrinsic property

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th, 2009

arXiv:0905.4368

25Roy A. Lacey, Stony Brook University; CATHIE-

TECHQM Workshop, BNL USA, Dec 14-18th, 2009

Summary

• PHENIX measurements are robust, pervasive and rife with opportunity for more detailed extraction of transport coefficients.

Care is required for model comparisons.

Current estimates of η/s indicate a small value

PHENIX Preliminary

Non-photonic electron flow

STAR: PRL98(2007) 192301

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“body-body” collisioncollision along the shortest axis

“tip-tip” collisioncollision along the longest axis

U + U

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V4 = k(V2)2 where k is the same for different particle species

v4/(v2)2 ratio for different particle species

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x10

x20

4 1~ 0.1, 0.2, 0.5 3s sT T

QCD Sonic Boom

Same-Side Jet

High pT trigger

**

Gives sound speed directly; Sets upper limit on viscosity.

M

cos M sc

Medium Response & Transport Coefficients

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th,

2009

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DataSimulated Deflected jet

Simulated Mach Cone

Data compatible with the presence of a away-side Mach Cone

Total 3PC jet correlations

True 3PC jet correlations

QCD Sonic Boom?

1~ 0.4, 24sc s

Roy A. Lacey, Stony Brook University; CATHIE-TECHQM Workshop, BNL USA, Dec 14-18th,

2009