Mach Ridge Cone B/M Peak Thingies

Tom TrainorBNL, May, 2008

Tom TrainorBNL, May, 2008

Minijets and their Interactions

Trainor 2

Agenda• Minijets in p-p spectra and correlations

• Minijets in A-A spectra and correlations

• Parton energy loss and QCD at small Q

• Minijets in pt fluctuations and correlations

restoring QCD to small-pt hadron physics

At what energy scale doesparton scattering and fragmentation stop?

Are A-A collisions thermalized?

Does hydro dominate?

pQCD

6 GeV/c

thermo/hydro or non-pQCD?

pt

spectrum structure

Trainor 3

yt

1/n s 1

/yt d

N/d

y t − S

0(y t)

H(nch,yt)nhns

yt

H(n

ch,y

t)

S0(yt)

H(nch,yt)

H0(yt)

nch 12345

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

2 2.5 3 3.5

10-3

10-2

10-1

1

1 2 3 4

Two-component p-p Spectra

pt (GeV/c)

1/n ch

1/p

t dN

/dp t

nch = 1

nch = 11.5

yt

1/n ch

1/y

t dN

/dy t

10-7

10-5

10-3

10-1

1010 310 510 710 9

101110131015

0 2 4 610

-610

-410

-21

10 210 410 610 8

101010121014

1 2 3 4

pt (GeV/c)

1/n s 1

/pt d

n/dp

t [(G

eV/c

)-2]

S0

total

n̂ch=11.5

1

H0/9

H0/140

yt

1/n s 1

/yt d

n/dy

t

S0

total

hard events

H0/9

H0

10-6

10-5

10-4

10-3

10-2

10-1

1

10

0 2 4 60

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

1 2 3 4

accurate separation of p-p longitudinal and transverse fragmentationPhys Rev D 74, 032006 (2006)

hard

soft

hard

{ }0ln ( ) /t t ty m p m≡ +

soft

hard

2003-2004

yt

1/n ch

1/y

t dn/

dyt

A B C

A

B

10-5

10-4

10-3

10-2

10-1

1 2 3 4

1.5 2

0.2

0.3

0.4

S0subtractS0

replot H0

STAR 200 GeV p-p

chn =

Trainor 4

pt (GeV/c)

1/n s 1

/pt d

N/d

p t

yt1/

n s 1/y

t dN

/dy t

10-7

10-5

10-3

10-1

1010 310 510 710 9

101110131015

0 2 4 610

-610

-410

-21

10 210 410 610 8

101010121014

1 2 3 4yt

1/n s 1

/yt d

N/d

y t − S

0(y t)

yt

H(n

ch,y

t)

S0(yt)

H(nch,yt)

H0(yt)

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

2 2.5 3 3.5

10-3

10-2

10-1

1

1 2 3 4

yt

∆ρ /

√ρre

f

y t

1

2

3

4

51

23

45

00.010.020.030.040.050.060.07

away

1

1.5

2

2.5

3

3.5

4

4.5

1 2 3 4

CI

1

1.5

2

2.5

3

3.5

4

4.5

1 2 3 4

Low-Q2 Partons in p-p Collisions

subtract soft reference

minijetfragments

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

√∆ρ∆ρ∆ρ∆ρ

-2-1.5

-1-0.5

00.5

11.5

2

-10

12

34

0

0.005

0.01

0.015

ρρ∆

∆φ ∆η

same side

1D 2Dp-p200 GeV

nch=1

nch=10

pt → yt

0.15 61pt (GeV/c)

nucleon fragments

φ∆

∆ρ /

√ρre

f

η ∆

2

02

4

-2

-1

0

1

2

-0.010

0.010.020.030.040.050.06

away side hadron pt ~ 0.6 GeV/c

yt1

yt2 yt2

∆ρ/∆ρ/∆ρ/∆ρ/√ρρρρref

nch

parton fragments

{ }0ln ( ) /t t ty m p m≡ +

minimum-bias: no trigger conditionJ Phys Conf Ser 27, 98 (2005); hep-ph/0506172

Trainor 5

p-p Correlations on (yt1,yt2)

yt

∆ρ /

√ρre

f

y t

1

2

3

4

51

23

45

00.010.020.030.040.050.060.070.08

yt

∆ρ /

√ρre

f

y t

1

2

3

4

51

23

45

00.010.020.030.040.050.060.07

yt

∆ρ /

√ρre

f

y t

1

2

3

4

51

23

45

00.010.020.030.040.050.060.07

yt

∆ρ /

√ρre

f

y t

1

2

3

4

51

23

45

00.010.020.030.040.050.060.070.08

-0.4

-0.2

0

0.2

0.4

0.6

0.8

1

φ∆

η ∆

-2

-1.5

-1

-0.5

0

0.5

1

1.5

2

0 2 4

ASSS

SS–same side

AS –away side

LS – like sign US – unlike sign

participant nucleon and parton fragmentation: first two-particle fragment distributions

0.151.0

10.0

pt (GeV/c)

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ refHBT

‘soft’away-side partonfragmentation isindependent ofcharge combination

same-side partonfragmentation isrestricted to US pairs

parton

parton parton

(except OPAL on ξ )

‘soft’

parton?

STAR preliminary

jet-jet

intra-jet

J Phys Conf Ser 27, 98 (2005); hep-ph/0506172

Trainor 6

p-p Correlations on (η∆,φ∆)

φ∆

∆ρ /

√ρre

f

η ∆

02

4

-2

-1

0

1

2

-0.2-0.1

00.10.20.30.40.50.60.70.8

φ∆

∆ρ /

√ρre

f

η ∆

02

4

-2

-1

0

1

2

-0.2-0.1

00.10.20.30.40.50.60.70.8

φ∆

∆ρ /

√ρre

f

η ∆

02

4

-2

-1

0

1

2

-0.050

0.050.1

0.150.2

0.250.3

0.350.4

φ∆

∆ρ /

√ρre

f

η ∆

02

4

-2

-1

0

1

2

-0.050

0.050.1

0.150.2

0.250.3

0.350.4

local charge and momentum conservation

yt1

y t2

1

1.5

2

2.5

3

3.5

4

4.5

1 2 3 4

HF

SF

SF –nucleon fragments (PDF)

HF –parton fragments (FDF)

LS – like sign US – unlike sign

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

away-side partonfragmentation is~ independent ofcharge combination

participant nucleon fragmentation reflects local measure conservation

HBT nucleon

parton

HBT?

parton

2D angular autocorrelations on difference axes

parton

STAR preliminary

J Phys Conf Ser 27, 98 (2005); hep-ph/0506172

Trainor 7

water dropsvrel = 6 m/s

φ∆

∆ρ /

√ρre

f

η ∆

02

4

-2

-1

0

1

2

-0.010

0.010.020.030.04

φ∆

∆ρ /

√ρre

f

η ∆

02

4

-2

-1

0

1

2

-0.0050

0.0050.01

0.0150.02

0.0250.03

0.0350.04

Low-Q2 Parton Angular Correlations

yt1

y t2

1

1.5

2

2.5

3

3.5

4

4.5

1 2 3 4

yt

∆ρ /

√ρre

f

y t

1

2

3

4

51

23

45

00.010.020.030.040.050.060.07

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

low-Q2 partons– non-pQCD

conventional high-ptleading-particle analysis: pQCD

p-p 200 GeV

STAR preliminary

small Q2

larger Q2

lo hi

non-pQCD pQCD

φ∆

η ∆

-2

-1.5

-1

-0.5

0

0.5

1

1.5

2

-1 0 1 2

φ∆

η ∆

-2

-1.5

-1

-0.5

0

0.5

1

1.5

2

-1 0 1 2

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

hi

lo

hydrodynamicsof parton collisions?

Q2

softest jets ever! big non-perturbative effects

no trigger particle

1:1 aspect

energy scale dependence

Gaussiansinusoid

Trainor 8

Minijet Deformation on (η,φ) in Au-Au

peripheral

N(r-1

)

-0.4-0.2

N(r-1

)

-0.4-0.2

N(r-1

)

-0.4-0.2

central

N(r-1

)

-0.4-0.2

νσ η,

σφ

ση

σφ

STAR preliminary

0.4

0.6

0.8

1

1.2

1.4

1 2 3 4 5

ηηηη

centrality

φφφφσσσσηηηη

σσσσφφφφ

130 GeV Au-Au

widths

minbias p-p

low Q2

fragmentation asymmetry reverses: p-p →→→→ Au-Au

130 GeV Au-Au mid-central

p-p

Au-Au

low Q2 p-p

η∆

φ∆-1.5 -1

-0.5 0

0.5 1

1.5 2-2-1

01

2

z

ηηηη φφφφ⊗⊗⊗ ⊗

Hubble expansion

p-p

HI

dramatic evolution with centrality

STAR preliminary

φ∆

η ∆

-2

-1.5

-1

-0.5

0

0.5

1

1.5

2

-1 0 1 2

2002-2003

Phys Rev C 73, 064907 (2006)

1:1

Trainor 9

0 2 4 6 8 10 12 14 16

-2) (

GeV

/c)

Tdy

dpTpπ

N)/(

22

(d

-1010

-710

-410

-110

210

510

310×0-12%210×10-20%

10×20-40%

MB (0-80%)

40-60%/10240-80%/10360-80%/10

(dE/dx)+πAuAu: (dE/dx)-πAuAu: (TOF)+πAuAu: (TOF)-πAuAu:

0 2 4 6 8 10 12

AuAu: p (dE/dx) (dE/dx)pAuAu:

AuAu: p (TOF) (TOF)pAuAu:

(GeV/c)T

Transverse Momentum p

pt Spectra – Standard Textconventional interpretation

• thermalized system

• state variables T, µµµµ• blast-wave modeling

• →→→→ radial flow ββββ

STAR: Phys. Rev. Lett. 97, 152301 (2006)

pions protonsAu-Au 200 GeV

pt (GeV/c)

2/n pa

rt 1

/2π

1/p t

d2 n / d

p t dη

protons

200 GeV Au-Au

A p-7.0

t

hydro ReCo pQCD

HNN

SNN

10-9

10-8

10-7

10-6

10-5

10-4

10-3

10-2

10-1

1

0 2 4 6 8 10

pt (GeV/c)

2/n pa

rt 1

/2π

1/p t

d2 n / d

p t dη

pions

200 GeV Au-Au

HNN

Spp

SNN

hydro ReCo pQCD

A p-7.5

t

200 GeV p-p

10-9

10-8

10-7

10-6

10-5

10-4

10-3

10-2

10-1

1

0 2 4 6 8 10

hydro? hydro?

differential plot format

direct comparison with

arXiv:0710.4504

two-component modelQCD power law

NN t NN tS (y ) +νH (y )

reference

Trainor 10

yt(π)

2/n pa

rt ρ

0p(y

tπ)

protons

200 GeV Au-Au

A e-5.0 yt

HNN

SNN

SNN

power lawminijetsnormali-zation

10-7

10-6

10-5

10-4

10-3

10-2

10-1

1.5 2 2.5 3 3.5 4 4.5 5

yt(π)

2/n pa

rt ρ

0π(y

tπ)

pions

200 GeV Au-Au

HNN

SNN

Ae-5.5 yt

power lawminijetsnormali-zation

200 GeV p-p

10-7

10-6

10-5

10-4

10-3

10-2

10-1

1.5 2 2.5 3 3.5 4 4.5 5

yt Spectrum and Hard Component

pion rapidity

no apparent hydro phenomena

{ }=t t t πy ln (m + p )/mparton fragments

parton fragments

0.5 1 2 4 6 10 pt (GeV/c)

NN t NN tS (y ) +νH (y )

QCD power

law

reference

yt(π)

ν H

AA =

2/n

part

ρA

A −

SN

N

protons

200 GeV Au-Au

A e-5.0yt

HNN

hydro ReCo pQCD10

-7

10-6

10-5

10-4

10-3

10-2

2 2.5 3 3.5 4 4.5 5

all parton fragments

fragments dominate centrality evolution

proton-to-pion anomaly?

arXiv:0710.4504

pion-to-proton anomaly?

subtract soft referencePhys. Rev. D 74, 032006 (2006) Phys. Rev. D 74, 034012 (2006)

NN tS (y )

yt(π)

ν H

AA =

2/n

part

ρA

A −

SN

N

Ae-5.5 yt

HNN

hydro ReCo pQCD

200 GeV p-p

pions

200 GeV Au-Au

10-7

10-6

10-5

10-4

10-3

10-2

2 2.5 3 3.5 4 4.5 5

p-p data

Trainor 11

yt(π)

ν H

AA =

2/n

part

ρ A

A −

SN

N

protons

200 GeV Au-Au

A e-5.0yt

HNN

hydro ReCo pQCD10

-7

10-6

10-5

10-4

10-3

10-2

2 2.5 3 3.5 4 4.5 5

yt(π)

ν H

AA =

2/n

part

ρ A

A −

SN

N

Ae-5.5 yt

HNN

hydro ReCo pQCD

200 GeV p-p

pions

200 GeV Au-Au

10-7

10-6

10-5

10-4

10-3

10-2

2 2.5 3 3.5 4 4.5 5

HAA

2( ; ) ( ; ) ( )AA t AA t NN t

part

H y y S yn

ν ν ρ ν= −data hard components

3.22.2

FD: fragment distribution

negativeboost ∆∆∆∆yt

?yt

yt

spectacular pionenhancement

yt

yt

and protons

(d)

X(p t1)

r

ˆ -

1

X(pt2 )

0.2 0.4 0.6 0.8

0.20.4

0.60.8

0

0.005

0.01

0.015

(a)

r

ˆ -

1

X(pt2 ) 0.15

2.00.5

1.0

pt (GeV/c)

0.2 0.4 0.6 0.8

0.20.4

0.60.8

-0.001

0

0.001

0.002

a long history

J. Phys. G 34 (2007) 799

the elephant in the living room

minijets

arXiv:0710.4504

QCD power

law

Trainor 12

RAA

yt

RA

A =

1/ν

2/n

part ρ

AA /

ρ pp

1 / ν

pions200 GeV Au-Au

pQCD

00.10.20.30.40.50.60.70.80.9

1

2 3 4 5

yt

RA

A =

1/ν

2/n

part ρ

AA /

ρ pp

1/ν

00.10.20.30.40.50.60.70.80.9

1

2 3 4 5

suppressed?

1 ( ) ( ; )

( ) ( )NN t AA t

pp t pp t

S y H y

S y H y

ν νν

+⋅+

protons

reference curves

jet quenching

mixes soft andhard components

2 /binary participantn nν ≡

? ?

yt

r AA =

HA

A /

HN

N

protons

200 GeV Au-Au

pQCD−∆yt dlog(H0) / dyt

∆yt = −0.26

60-80%

0-12%

0.2

0.3

0.4

0.50.60.70.80.9

1

2

3

4

5

2 2.5 3 3.5 4 4.5 5yt

r AA =

HA

A /

HN

N

pions

200 GeV Au-Au

−∆yt dlog(H0) / dyt

∆yt = −0.285

A = 0.21, ∆yt = 0

200 GeV p-p

0-12%

60-80%

pQCD

0.2

0.3

0.4

0.50.60.70.80.9

1

2

3

4

5

2 2.5 3 3.5 4 4.5 5

( ; )

( )AA t

NN t

H y

H y

ν

hard-component ratios all deviations from the reference

partonfragmentation

only

rAA

arXiv:0710.4504

reference

excess!

Trainor 13

∆yt and Parton Energy Loss

yt

r AA =

HA

A /

HN

N

200 GeV Au-Au

pions

yt

r AA =

HA

A /

HN

Nprotonsprotonsprotonsprotons

1

10

2 3 4 5

1

10

2 3 4 5

log[ ( ; )]

( ) log[ ( )] /AA t

t NN t t t

r y

y d H y y dy

νν δ

≈− ∆ −

δδδδyt

( ; ) ( [ ])AA t NN t tH y AH y yν ν≈ + ∆if ‘energy loss’ is a negative boost

then by Taylor expansion

modeling rAA

log[ ( )] /t NN t ty d H y dy−∆

dashed model curves fully describe data

anomalous

naïve model

t yty n

e∆

arXiv:0710.4504

ν

−∆E

/ E

, −∆

y t

20 GeV

Ejet = 10 GeV

0

0.05

0.1

0.15

0.2

0.25

0.3

1 2 3 4 5 6

200 GeV

Eloss negative boost ∆∆∆∆yt

theory ∆∆∆∆E/E (curves) from I. Vitev

Vitev

star preliminary

displacements may indicatecolor screeningof partons

Trainor 14

yt

S AA,

ν H

AA

π

p

p

ν = 1

ν = 6

π

pt (GeV/c)

ρ prot

on /

ρ pion

ν = 1

ν = 6

protons

antiprotons

10-8

10-7

10-6

10-5

10-4

10-3

10-2

10-1

1 2 3 4 5

10-1

1

0 5 10

The Proton vs Pion Anomaly

( ) ( ; )

( ) ( ; )proton NNp t AAp t

pion NN t AA t

S y H y

S y H yπ π

ρ ν νρ ν ν

+=

+ratio mixes soft and hard components

the Au-Au “anomaly” isonly a factor 2×

0 2 4 6 8 10 12

Rat

ios

-110

1

+π(a)p/ 0-12% Au+Au60-80% Au+Aud+Au

0 2 4 6 8 10 12

-π/p(b) )-π++π)/(p:(p+-e+eHwa:RecombinationFries:Coalescence+Jet

)-π++π)/(p:(p+-e+eHwa:RecombinationFries:Coalescence+Jet

(GeV/c)T

Transverse Momentum p

good agreement

Phys. Rev. Lett. 97, 152301 (2006)

ReCo, or partonenergy loss?

model summary

spectrum ratio not comparable to fragmentation function ratios

e++++-e−−−−

( ; ) / ( ; )AAp t AA tH y H yπν νis directly interpretable

p

p

arXiv:0710.4504

Trainor 15

limited spectrum information

Spectrum Summary

• Spectra have two primary components

• Nucleon and parton fragmentation dominate

• Deviations from reference: parton energy loss

• Hydrodynamics plays no evident role

0 2 4 6 8 10 12 14 16

-2) (

GeV

/c)

Tdy

dpTpπ

N)/(

22

(d

-1010

-710

-410

-110

210

510

310×0-12%210×10-20%

10×20-40%

MB (0-80%)

40-60%/10240-80%/10360-80%/10

(dE/dx)+πAuAu: (dE/dx)-πAuAu: (TOF)+πAuAu: (TOF)-πAuAu:

0 2 4 6 8 10 12

AuAu: p (dE/dx) (dE/dx)pAuAu:

AuAu: p (TOF) (TOF)pAuAu:

(GeV/c)T

Transverse Momentum p

all spectrum informationyt

r AA =

HA

A /

HN

N

pions

200 GeV Au-Au

−∆yt dlog(H0) / dyt

∆yt = −0.285

A = 0.21, ∆yt = 0

200 GeV p-p

0-12%

60-80%

pQCD

0.2

0.3

0.4

0.50.60.70.80.9

1

2

3

4

5

2 2.5 3 3.5 4 4.5 5yt

r AA =

HA

A /

HN

N

protons

200 GeV Au-Au

pQCD−∆yt dlog(H0) / dyt

∆yt = −0.26

60-80%

0-12%

0.2

0.3

0.4

0.50.60.70.80.9

1

2

3

4

5

2 2.5 3 3.5 4 4.5 5

hard-component ratiosconventional spectra

pion-to-proton vs proton-to-piontwo anomalies!

Trainor 16

2D Angular Autocorrelations

peripheral

central

∆ ∆

ref

∆ρ(η ,φ )

ρ

azimuthrapidity

200 GeV Au-Au star preliminarystar preliminary

Michael Daugherity (U. Texas – Austin)

N-NAu-Au

↔↔↔↔

η ∆

φ∆

∆ρ /

√ρre

f

-2-1.5

-1-0.5

00.5

11.5

2

-10

12

34

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

η ∆

φ∆

∆ρ /

√ρre

f

-2-1.5

-1-0.5

00.5

11.5

2

-10

12

34

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

η ∆

φ∆

∆ρ /

√ρre

f

-2-1.5

-1-0.5

00.5

11.5

2

-10

12

34

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

η ∆

φ∆

∆ρ /

√ρre

f

-2-1.5

-1-0.5

00.5

11.5

2

-10

12

34

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

=

++

2D fits

minijets

quadrupole ↔↔↔↔ elliptic flowarXiv:0704.1674

Trainor 17

Modeling 2D Autocorrelations

=

η ∆

φ∆

∆ρ /

√ρre

f

-2-1.5

-1-0.5

00.5

11.5

2

-10

12

34

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

+

η ∆

φ∆

∆ρ /

√ρre

f

-2-1.5

-1-0.5

00.5

11.5

2

-10

12

34

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

η ∆

φ∆

∆ρ /

√ρre

f

-2-1.5

-1-0.5

00.5

11.5

2

-10

12

34

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

η ∆

φ∆

∆ρ /

√ρre

f

-2-1.5

-1-0.5

00.5

11.5

2

-10

12

34

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

+ +

η ∆

φ∆

∆ρ /

√ρre

f

-2-1.5

-1-0.5

00.5

11.5

2

-10

12

34

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

η ∆

φ∆

∆ρ /

√ρre

f

-2-1.5

-1-0.5

00.5

11.5

2

-10

12

34

-0.2

-0.1

0

0.1

0.2

0.3

0.4

0.5

large“nonflow” small “flow”

[2]A

ref

ρρ

∆[1]A

ref

ρρ

∆

( , )A

ref

ρ η φρ ∆ ∆

∆

dipole quadrupole

same-side peak

David Kettler model fits

star preliminary

5-10% central Au-Au 200 GeV

∆η∆φ

∆η∆φ HBT, electronsno physicalmodel

A A refρ ρ ρ∆ ≡ −

Trainor 18

ν

∆ρ[2

] / √

ρ ref

1D-proj-200X[2]-200X[2]-62

v2{2}v2{4}

17 GeV

62 GeV

200 GeV

{2}

{4}

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

2 4 6ν

v 2

17 GeV

62 GeV

200 GeV

v2{2}

N-N0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08

0.09

2 4 6

Elliptic Flow or New QCD Physics?

model fits

= ≡2 22 2

ref

∆ρ[2] V n v {2D}2πn 2πρ

transform

star preliminary

David Kettler (U. Washington – Seattle)

~v2{EP}

{ }2v 2D

≡ binary participantν 2n /n

hydro model

star preliminary

conventional statisticPearson’s covariance Ollitrault/Voloshin

quadrupole amplitude conventional v2

Trainor 19

R(√sNN) nbin(b)

1/ε2 ∆

ρ[2]

/ √ρ

ref

0.0045 R nbin

200 GeV

62 GeV17 GeV

10-2

10-1

1

10

1 10 102

103

Does “Elliptic Flow” Relate to a Medium?

star preliminary ηηηη width

peripheral trend

62 GeV

200 GeV

amplitude

minijet same-side peak

transparent nuclei

sharp transitions

ν

−∆E

/ E, −

∆yt

20 GeV

Ejet = 10 GeV

0

0.05

0.1

0.15

0.2

0.25

0.3

1 2 3 4 5 6

no transition

medium?

no medium?

star preliminary

star preliminary

parton energy loss, spectra

peakvolume

M. Daugherity, R.L. Ray, UT (Austin)

I. Vitev

quadrupole

8×

εεεεoptical

Trainor 20

⟨pt⟩ Fluctuations and pt Correlations

δη

∆σ2 pt

:n (G

eV/c

)2

δφ 00.5

11.5

2

02

46

00.0050.01

0.0150.02

0.0250.03

0.0350.04

0.045

tps)/tp-ñtpá(·n

-5 -4 -3 -2 -1 0 1 2 3 4 5

ev

en

t n

um

be

r N

1

10

102

103

104

full STAR acceptance

variance excess

scale dependence

η ∆

∆ρ /

√ρre

f (G

eV/c

)2

φ∆-2

-1

0

1

2

02

4

-0.01-0.005

00.0050.01

0.0150.02

0.0250.03

0.035

fluctuationinversion

pt autocorrelation

⟨⟨⟨⟨pt⟩⟩⟩⟩ fluctuations

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

η ∆

∆ρ /

√ρre

f (G

eV/c

)2

φ∆

η ∆

φ∆

η ∆

∆ρ /

√ρre

f (G

eV/c

)2

φ∆

-2

-1

0

1

2

02

4

00.00250.005

0.00750.01

0.01250.015

0.01750.02

-2

-1

0

1

2

02

4

00.00250.005

0.00750.01

0.01250.015

0.01750.02

-2

-1

0

1

2

02

4

-0.003-0.002-0.001

00.0010.0020.0030.0040.0050.006

-2

-1

0

1

2

02

4

-0.01-0.008-0.006-0.004-0.002

00.0020.0040.006

20-30% central

data − fit peakfit residuals

fitdatafit peak

Au-Au 200 GeVB1

B3

B2

Rosetta stone for fluctuationand correlation analysis

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

subtract multipoles STAR preliminary

tps)/tp-ñtpá(·n

-5 -4 -3 -2 -1 0 1 2 3 4 5

Nev

tN

/e

vt

d

-5

0

5

10

15

20

25

nu

mb

er

of

ev

en

t s

Ne

vt

1

10

102

103

104

STAR Au-Au s = 130 GeVNN

J. Phys. G 31, 809 (2005)

J. Phys. G 32, L37 (2006)

Trainor 21

A-A centralityν

B1,

B2,

B3

(GeV

/c)2

B1−B2 B3

ν

σ η1, σ

φ1

ση1

σφ1

0

0.005

0.01

0.015

0.02

0.025

0.03

0.035

0.04

0.045

1 2 3 4 5 60.4

0.45

0.5

0.55

0.6

0.65

0.7

0.75

0.8

1 2 3 4 5 6

Recoil Response of the QCD Mediumred shifts and blue shifts Au-Au – 200 GeV

recoil

coloredmedium?

low-Q2 ‘jet’

η

Hubble flow

2

-2

-1

0

1

2

02

4

-0.01-0.008-0.006-0.004-0.002

00.0020.0040.006

data −−−− fit peakη ∆

φ∆-2

-1

0

1

2

02

4

-0.00250

0.00250.005

0.00750.01

0.01250.015

fragments

η ∆∆ρ /

√ρre

f (G

eV/c

)2

φ∆-2

-1

0

1

2

02

4

0

0.0010.0020.0030.0040.005

∆ρ/

∆ρ/

∆ρ/

∆ρ/√

ρρ ρρ ref

pt autocorrelationsp-p 200 GeV

Au-Au 200 GeV

Hijing quench-on

p-p

medium response

STAR preliminary

Trainor 22

The View from the Ridge• p/ππππspectrumanomaly is part of fragmentation

• Related π/π/π/π/p spectrum anomaly is larger!

• Jet “ridge” is the samefragmentation anomaly

• The “ridge” is not an isolated entity

• What evidenceexists for a unique “medium”

a couple of low-Q2

partons converse

YEP, SON,WE HAVE MET

THE MEDIUM

AND HE IS US

IT’S HARD

MOVIN’THROUGH

THIS STUFF

Porky and Pogo

Minijets and their Interactions

QCD processes at all energy scales

Minijets dominate nuclear collisions

Non-pQCD plays a central role

Hydro is not relevant

New QCD phenomena emerge at RHIC