Elliptic and triangular flow measurements--- interplay between soft and hard process --ShinIchi Esumi
Univ. of Tsukuba

Contents
higher order event anisotropy
v3 or ridge / mach-conevn measurements with Φn at forward η
correlation with large rapidity gap
medium property with hard probeyHigher order event anisotropy --- v3 --black-disk collision, sign-flipping v3 like v1
initial geometrical fluctuation, no-sign-flipping v3x

arXiv:1003.0194
Reaction Plane (x-z)

xzyyxSome couplings between“mach-cone-like and ridge-likeemissions” and v3 are
expected to be there!

PRL104 (2010) 062301

What is the origin andwhat is the consequence?

shoulderridge

RXNMPC

2cm Pb converterin front(reaction plane detector)

PbW04(muon pistonEM-calorimeter)dN/dηBBC-505η

(beam-beam quartzCherenkov detector)(zero degree n calorimeter
ZDC/SMD /shower max detector)
CNT(PHENIX central tracking arm)

σn = <cos n(Φn(meas.) - Φn(true))>reaction plane resolution of n-th order plane
200GeV Au+Au
PHENIX Preliminary

n=2 RXN
n=3 RXN

RXN |η| = 1.0 ~ 2.8
MPC |η| = 3.1~ 3.7

n=4 RXN
n=2 MPC
n=3 MPCtan nΦn =centrality (%)
positive correlation in Φ3 between opposite η up to +/− 3 ~ 4no-sign flipping in Φ3, which is an indication initial geometrical fluctuation
Φn resolution estimated from Forward-Backward correlation
Φn{true} can be different for different orderΣi {wi sin nφi }Σi {wi cos nφi }Correlation between different harmonics (w.r.t spectator Φ1)<cos k(ΦkA - Φ1C)><cos k(ΦkB- Φ1C)>(%)<sin k(ΦkA - Φ1C)><sin k(ΦkB - Φ1C)>

A: BBC(S) η[-3.9,-3.1]
B: BBC(N) η[3.1,3.9](N-side flipped to combine)

C: ZDC(S+N) |η|>5<cos or sin k(Φk - Φ1)>

101 (Φ1 - Φ1ZDC(-))

0200GeV Au+Au
PHENIX Preliminary

602 (Φ2 - Φ1ZDC(-))

0.06

3 (Φ3 - Φ1ZDC(-))

0centrality (%)
clear sign-flipping in v1 , clear positive v2
indication of sign-flipping in v3 , sign(v1) = sign(v3)case1

case2

beam rapidity

case3

beam rapidity

beam rapidity

spectator

net-baryon
ridge likenearn-even :vn(η) = vn(-η)

fluctuating
initial condition

n-odd :
vn(η) = -vn(-η)
midrapidity

participant

midrapidity

midrapidity
all n :
vn(η) = vn(-η)

near side
jetaway sidejetmach-conelike away

vn{EP} at mid-rapidity with forward Φn

Φn RXN (|η|=1.0~2.8)
MPC(|η|=3.1~3.7)
BBC(|η|=3.1~3.9)

200GeV Au+Au -> charged particles (|η|<0.35)

vn{EP}

0~10%

10~20%

20~30%

30~40%

40~50%

50~60%PHENIX Preliminary
0.2

v2 {Φ2 forw.η}
v3 {Φ3 forw.η} no-sign-flipping v3
v4 {Φ4 forw.η}

0.1

0.0024024024pT (GeV/c)
systematic errors are defined by the variations with Φn from different η andfrom different methods including central-forward 2-particle correlation.
Therefore it could include some physics biases.

Comparison with Hydro calculationv3{2-part. cent.-cent.}
v3{ψ3 forward}

small η gap,
bulk + jet + ?

arxiv: 1007.5469
Glauber initial condition
η/s = 1/4πlarge η gap,bulk flow only

good agreement between data and theory!

central-central 2-part. correlation with ∆η dependence

200GeV Au+Au
0-20%, inc. γ-had.

0<|∆η|<0.1

0.1<|∆η|<0.3

0.3<|∆η|<0.5

0.5<|∆η|<0.7

2-part. correlation between central and forward
CNT − RXN

CNT − MPC

CNT: central tracks
mid-rapidity (|η|<0.35)
charged hadrons
pT=2~4(GeV/c)C2(∆φ)
C2(∆φ) - F(∆φ) + 1

200GeV Au+Au 20~30%
PHENIX PreliminaryF(x) = A {1 + 2Σ k=1~2 [pkcos(kx)] }F(x) = A {1 + 2Σ k=1~4 [pkcos(kx)] }RXN: reaction plane detector
forward |η|=1.0~2.8
all cells/hits (charge weightingwith Pb converter)
MPC: muon piston calorimeter
forward EM-cal |η|=3.1~3.7
all cells/towers (eT weighting)pn = vnA × vnBclear 3rd moment in
two-particle correlation
with large η gap∆φ = φ (CNT) − φ (RXN)∆φ = φ (CNT) − φ (MPC)thin side mach-cone(shoulder region)
φ ASSO-φ TRIG>0near side(triggerdirection)

Probe the transverse
geometry and/or dynamics
with triggered correlation

φ ASSO-φ TRIG<0away side(head region)

thick side mach-cone(shoulder region)
φ ASSO-φ TRIG<0Trig.

200GeV Au+Au -> h-h(pTTrig=2~4GeV/c, pTAsso=1~2GeV/c)v2(v4{Φ2})-only subtraction
PHENIX preliminary

penetrationTrig.

surface

R.P.

R.P.

Trig.
Trig.

SQM09, F. Wang

∆φaveraged∆η cut to select ridge∆φmirrored

AMPT simulation

ηTrig.~ -2

ηTrig.~ 0Probe the longitudinalgeometry and/or dynamics
with triggered correlation

mirror symmetric-404∆η = ηAsso. - ηTrig.

Heavy Ion Pub 18/Mar/2011, Osaka, JapanT.Todoroki, Univ. of Tsukuba

Hard Probe 2010, Yue Shi
Lai

Increasing jet
cone radius andincluding low pTparticles would
recover initial
parton energy.

High Tower Trigger (HT) : (ηxφ)=(0.05x0.05) ET>5.4GeV

RHIC-AGS’09, J. Putschke

γ,Jet,π0 - hadron correlation--- Comparisons are the most important! ---r to rgyes
clo n enedan artores
lperg
Clo initiagtriathemmraGgegi) tr
Rrgeal(Jetrgegi) tr
Rallm(steJerggi) trndroia sab0 (hπacefrsu sersmo gy lo
dan enerer
mo en bygiv

Back-to-back
Jet Calorimeter
for LHC-ALICE
experiment

D-CAL
upgradecone size dependent jet suppression
can be understood by recovering ofenergy loss with a larger cone.
can be used to give a controlledbias in analysis and in triggering.

External Reaction Plane determinationin ALICE for vn measurement in TPC* V0 (2 arms, 4 rings/arm, 8 segments/ring)
V0C η : [-3.7 ~ -3.2 ~ -2.7 ~ -2.2 ~ -1.7]
V0A η : [ 2.8 ~ 3.4 ~ 3.9 ~ 4.5 ~ 5.1]

* T0 (2 arms, 1 ring/arm, 12 PMTs/ring)
T0C η : [-3.3 ~ -2.9]
T0A η : [ 4.5 ~ 5.0]

* ZDC (2 arms, 4 segments in x/y)

jet, di-jet and multi-particle correlation with various conditions
ηJet , ηTrig.

φJet , φTrig.
8φJet , φTrig.

7766543543
1182213254768Summary•Indication of weak sign-flipping (true) v3•Strong non-sign flipping v3 observed with wide rapidity gap,
which is consistent with initial geometrical fluctuation,(probably followed by collective triangular expansion)•Strong coupling of triggered correlation withgeometry/dynamics•Jet tagging with various cone radius to be compared withdirect photon or single hadron tagging

collectivity (v2) in high mult. p+p
coupled with initial fluctuation

CMS, CERN Seminar, Sept. 21, 2010
CERN-PH-EP/2010-031
arXiv:1009.4122v1

Method of event plane determination(1) Detector calibration / cell-by-cell calibration(2) Q-vector, re-centering, normalization of width
Q{n}x = Σi { wi cos (n φi) }Q’{n}x = (Q{n}x - <Q{n}x>) / σQ{n}x
Q{n}y = Σi { wi sin (n φi) }Q’{n}y = (Q{n}y - <Q{n}y>) / σQ{n}yQ{1}xZDC = Σi { wi xi } / Σi { wi }Q{1}yZDC = Σi { wi yi } / Σi { wi }(3) n-th harmonics reaction planeΦ{n} = atan2 (Q’{n}y , Q’{n}x) / n(4) Fourier flattening (Sergei’s+Art’s method paper)n Φ’{n} = n Φ{n} + Σi (2/i) { - <sin(i n Φ{n})> cos(i n Φ{n}) + <cos(i n Φ{n})> sin(i n Φ{n}) }(5) measure vn w.r.t. Φn and correct for E.P. resolution

2-particle correlation among 3-sub detectors
ForwardHit (F), BackwardHit (B), CentralTrack (C)(1) measure dφ distribution between 2 detectors weighting by the hit amplitude(2) normalize by the event mixing to make correlation functions for 3 combinations(3) fit the correlation with Fourier function to extract vnFvnB, vnFvnC and vnBvnC(4) vnF(Hit) and vnB(Hit) can be determined as a function of centrality(5) vnC(Track) can be determined as a function of centrality and pT

Correlation between different harmonics (opposite η arms)(%)<cos k(ΦmA - ΦnB)><cos k(ΦmB- ΦnA)>

4<cos or sin k(Φm - Φn)>

2 (Φ1 - Φ2)0.1

0<sin k(ΦmA - ΦnB)><sin k(ΦmB - ΦnA)>
3 (Φ1 - Φ3)

0.1A: RXN(S) η[-2.8,-1.0]
B: MPC(N) η[3.1,3.7]
6 (Φ2 - Φ3)

4 (Φ2 - Φ4)000200GeV Au+Au
PHENIX Preliminary

clear positive correlation in Φ1−Φ2 , Φ2−Φ4very weak negative correlation in Φ1−Φ3
no significant correlation in Φ2−Φ350
centrality (%)

100

What we have observed with Φn(1) clear correlation between Φ1 and Φ2 as well as Φ2 and Φ4, where v2,4
have also been measured with lower order harmonic planes(2) participant (pion dominant) v1 is opposite with respect to spectator v1
as expected (already seen at RHIC and other energies)(3) weak correlation between Φ1 and Φ3 is seen as a signature of true v3
with sign-flipping at mid-rapidity, same sign for both v1 and v3(4) no significant correlation between Φ2 and Φ3 is seen within current
statistical accuracy(5) clear correlations of same order Φ3,(4) are seen between detectors
with wide rapidity gap, which is consistent with initial geometricalparticipant fluctuation commonly over wide rapidity space(6) The origin can also be jet-medium correlation, which can spread overwide rapidity space (coupled with earlier stage)