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High-energy heavy-ion collisions viewed with v 2 , singles and HBT measurements.

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High-energy heavy-ion collisions viewed

with v2, singles and HBT measurements.

ShinIchi Esumi, Univ. of Tsukuba

v2 – initial geometry and partonic flow and jets

singles(ratio and spectra) – chemical/thermal f.o.

HBT – space-time information

ShinIchi Esumi, Univ. of Tsukuba

S. Bass

Elastic scattering

and kinetic freeze-out

TC=170 MeV

eC=0.5 GeV/fm3

Hadronic interactionand chemical freeze-out

QGP and

Hydro. expansion

initial state

?

?

Time

pre-equilibrium

Hadronization

Decreasing energy density

高エネルギー重イオン衝突

における衝突領域の時間発展

v2

particle ratio

particle spectra

HBT

ShinIchi Esumi, Univ. of Tsukuba

Au+Au collisions in

sqrt(sNN)=200GeV with

Relativistic Heavy Ion

Collider (RHIC) at BNL

PHENIX

mid-rapidity hadron/electron/

photon spectrometer

Forward-rapidity muon

spectrometer

ShinIchi Esumi, Univ. of Tsukuba

BBC/ZDC : centrality

Dch/PC1,2,3 : tracking

Tof : hadron PID

Rich : electron PID

Emcal : electron/photon PID

ShinIchi Esumi, Univ. of Tsukuba

dNch/dh

-6 -3 0 3 6

h

Reaction plane detectors in PHENIX

CNT

Beam-beam counter

(BBC) |h|=3~4

64pmts in each BBC

charged particles

Muon arm +

Silicon multiplicity

(MVD) endcap

MVD

BBC

ZDC/

SMD

collision point

South

North

beam line

Zero Degree Calorimeter

Shower-Max Detector

Spectator neutron energy

Beam position

two central arms

(CNT) |h|<0.35

Dch,PCs,TOF,EMCAL

tracking, momentum, PID

ShinIchi Esumi, Univ. of Tsukuba

parton

hadrons

Target

Projectile

parton

Reaction plane

Reaction plane

b:impact parameter

initial geometry

final momentum anisotropy

A+A

p+p

Experimentally, the R.P. is defined by the event anisotropy by itself.

ShinIchi Esumi, Univ. of Tsukuba

collision

vertex

BBC

MVD

ShinIchi Esumi, Univ. of Tsukuba

LED flasher

SMD1 (South)

SMD2 (North)

16ch. PMT “M16”

Y (cm)

Shower

Maximum

Detector

(SMD)

beam spot

distribution

X (cm)

X (cm)

WLS fibers

FSMD1

FSMD2

(Y-CY)/sY

Scintillator strips

horizontal-strips

vertical-strips

(X-CX)/sX

(X-CX)/sX

SMD

ShinIchi Esumi, Univ. of Tsukuba

FBBC1-p vs FBBC2

FSMD1-p vs FSMD2

FSMD-p vs FBBC

back-to-back

back-to-back

spectator neutrons vs

ps from participants

are flowing opposite.

F2BBC1vs F2BBC2

F2MVD1vs F2MVD2

F2BBCvs F2MVD

ShinIchi Esumi, Univ. of Tsukuba

neutron spectator

charged particles

(pions) at mid h

beam

beam line

reaction plane

-p 0 p fparticle-FR.P. (rad)

ShinIchi Esumi, Univ. of Tsukuba

indication of v2 saturation at RHIC energy

PHOBOS : nucl-ex/0406021

PHENIX Preliminary

ShinIchi Esumi, Univ. of Tsukuba

Thermal model with blast-wave

hydro is really good to be truth!!

What will happen with resonances?

Resonance effects are important in single spectra, but not too much in v2, because of pT shift of heavy particles having smaller v2 and linear pT dependence of v2.

ShinIchi Esumi, Univ. of Tsukuba

pT shift is the dominant effect compared to the smearing given by the opening angle.

Phys.Lett. B597 (2004) 328-332, X. Dong et.al.

Phys.Rev. C70 (2004) 024901, V. Greco et.al

Pion deviation is explained

by resonance decays

ShinIchi Esumi, Univ. of Tsukuba

Data prefer “quark coalescence / recombination” based picture rather than “hydro + jet” picture at intermediate pT.

quark

coalescence

QGP

hydro + jet

recombination + fragmentation

ShinIchi Esumi, Univ. of Tsukuba

minimum bias Au+Au at sNN = 200 GeV

Almost NO

mass ordering

PHENIX preliminary

Similar effect from the time-difference is seen in v2

quark + hadron flow

SPS

PHENIX preliminary

初期離脱

some remaining

mass ordering

Tfo

ShinIchi Esumi, Univ. of Tsukuba

hydro + jet

recombination + fragmentation

Jets dominate the high pT part of spectra.

And they (jets)

are suppressed.

PHENIX

STAR

ShinIchi Esumi, Univ. of Tsukuba

0.906 < < 1.042

charmed e+,e- pT distribution

dN/dy = A (Ncoll)

PHENIX Preliminary

PHENIX Preliminary

Charm quarks are not suppressed w.r.t. binary scaling compared to the light quarks, but it could be enhanced and suppressed (looked like binary scaled). The v2 of charm would give a hint for the answer to the question.

ShinIchi Esumi, Univ. of Tsukuba

inclusive e+e- v2

charmed e+e- v2

STAR SQM04

If charm quarks also flow, charm quarks are thermalized and / or suppressed similarly to the light quarks.

ShinIchi Esumi, Univ. of Tsukuba

Inclusive Single g

1 + (g pQCD direct x Ncoll) / gphenix backgrd Vogelsang NLO

Run2 AuAu 200 GeV

1 + (g pQCD direct x Ncoll) / (gphenix pp backgrd x Ncoll)

PHENIX Preliminary

Direct photons are enhanced w.r.t. p0 production, but it’s just because p0 is suppressed, and the direct photons are in fact binary scaled.

[w/ the real, suppressed background]

PHENIX Preliminary

AuAu 200 GeV

Central 0-10%

pT (GeV/c)

ShinIchi Esumi, Univ. of Tsukuba

vertical bar : stat. error

curves, gray box : sys. error

Note :

Inclusive photon = including all of the decay effect from hadrons

, 200 GeV Au+Au

, 200 GeV Au+Au

, 200 GeV Au+Au

phenix preliminary

phenix preliminary

phenix preliminary

The difference here and the g/p0 ratio will give us a measure of direct g v2.

pT [GeV/c]

Direct photons should not have any flow by definition, but …

Alternatively g/p0 ratio can be measured by assuming v2g=0.

ShinIchi Esumi, Univ. of Tsukuba

hadron-hadron correlation (full pT reference)

1.1

1.0

0.9

Au+Au 200GeV PHENIX preliminary

1<pT(associate)<1.5GeV

Another way to get the v2 : (v2)2 is given by the pair correlation

harmonic

function

fixed to the

measured v2

harmonic +

near-side +

Far-side

Gauss

function fit

harmonic +

near-side

Gauss

function fit

pure

harmonic

function fit

1.1

1.0

0.9

2.5<pT(associate)<3GeV

Ways to reduce the jet correlation with additional Gauss terms

0. p

0. p

0. p

f1-f2 (rad)

A{1+2 (v2)2 cos(2Df)} + Gauss term

ShinIchi Esumi, Univ. of Tsukuba

PHENIX Preliminary

Reac. plane v2 does have less non-flow because of the h gap.

Non-flow are removed in 2 part. corr. 2nd cumulant …

ShinIchi Esumi, Univ. of Tsukuba

phenix preliminary

}nucl-ex/0305013

Au+Au 200 GeV

Au+Au 200 GeV

v2 reduction of charged particles in the previous page could be enlarged by the baryon/meson ratio.

ShinIchi Esumi, Univ. of Tsukuba

The difference here is given by the real flow (v2).

STAR

2 particle correlation

(v2 + non-flow)

ShinIchi Esumi, Univ. of Tsukuba

charged particle v2

STAR : nucl-ex/0409033

non-flow reduced

v2{2}

v2{RP}

v2{RP}

v2{2}

v2{4}

STAR Preliminary

Jet suppression ends somewhere …

ShinIchi Esumi, Univ. of Tsukuba

recombination + fragmentation

old STAR data

semi-old STAR data

no jet-quenching

ShinIchi Esumi, Univ. of Tsukuba

in-plane pair

STAR preliminary

in between

out-of-plane pair

20-60%

trigger particle

in the selected

angular window

r.p.

track1 - track2|

20-60%

Q: Are jets source of v2?

Q: Does reaction zone

make flowing jets?

leading parton

hadrons

Proof of the jet quenching

and the source of v2 at high pT

ShinIchi Esumi, Univ. of Tsukuba

three curves are fixed by

measured v2 and resolution

coalescence of jet-fragmentation could be one of the source of v2

flow subtracted

pTtrigger > 3GeV/c

1 < pTassociated < 2 GeV/c

in-plane pair

in between pair

out-of-plane pair

real/mixed

PHENIX preliminary

PHENIX preliminary

0 p

0 p

Df (rad)

Df (rad)

ShinIchi Esumi, Univ. of Tsukuba

Associated particles pT distributions

4 < pTtrig < 6 GeV/c

re-distributed lost energy

ShinIchi Esumi, Univ. of Tsukuba

粒子比

RHIC

非弾性散乱の終了

化学的フリーズアウト

Tch : 化学的フリーズアウト温度

mB : バリオン化学ポテンシャル

mｓ: ストレンジネス化学ポテンシャル

gｓ: ストレンジネス平衡

SPS

ShinIchi Esumi, Univ. of Tsukuba

弾性散乱の終了

熱力学的フリーズアウト

ShinIchi Esumi, Univ. of Tsukuba

TC

Tch

<b>

200

400

600

dNch/dh

history of temperature

initial temperature

from the energy density

phase transition at

critical temperature

chemical freeze-out

temperature

thermal freeze-out

temperature

ShinIchi Esumi, Univ. of Tsukuba

parton flow ?

early freeze-out

ShinIchi Esumi, Univ. of Tsukuba

クォーク数(バリオン／メソン）によるスケーリング則

ShinIchi Esumi, Univ. of Tsukuba

検出器

Dx

Dp

１粒子分布

２粒子相関

熱的フリーズアウト温度

流体モデル

横方向流体速度

横方向運動量

ShinIchi Esumi, Univ. of Tsukuba

PHENIX, 200GeV Au+Au

ShinIchi Esumi, Univ. of Tsukuba

coulomb

correction

ShinIchi Esumi, Univ. of Tsukuba

NA49

ShinIchi Esumi, Univ. of Tsukuba

ShinIchi Esumi, Univ. of Tsukuba

Mean free path at freeze-out:

√s=200 GeV

90

90

d+Au

Vf (fm3)

80

80

N (fm2)

70

70

60

60

50

50

40

40

30

30

p+p

20

20

10

10

preliminary

0

ShinIchi Esumi, Univ. of Tsukuba

ShinIchi Esumi, Univ. of Tsukuba

(0) RQMD v2.4 original

(1) pT vector randomized

(2) pT vector aligned with rT vector

(3) stronger |pT| vs time correlation

(4) apply (2) and (3) simultaneously

ShinIchi Esumi, Univ. of Tsukuba

The ellipse is still vertical (negative w.r.t. R.P.), but |e| is smaller than at AGS (closer to circle)

ShinIchi Esumi, Univ. of Tsukuba

einitial

efinal

ShinIchi Esumi, Univ. of Tsukuba

PHENIX Preliminary

E895

E895

new source imaging technique (coulomb included)

indication of the large (exponential/non-gaussian) source

core-core / halo-halo / core-halo cross term

ShinIchi Esumi, Univ. of Tsukuba

PHENIX Preliminary

PHENIX Preliminary

ShinIchi Esumi, Univ. of Tsukuba

blast-wave model (fit)

ShinIchi Esumi, Univ. of Tsukuba

Buda-Lund model (fit)

Spectra

Source size (HBT)

nucl-th/0311102 and nucl-th/0310040

ShinIchi Esumi, Univ. of Tsukuba

v2 and HBT from AMPT?

σ ~ 10 mb

σ < 6 mb (~ 3 mb?)

ShinIchi Esumi, Univ. of Tsukuba

initial geometry and partonic (and hadronic) flow

v2 and its relation to jet quenching

(partonic and) hadronic flow + chemical/thermal freeze-out

singles (ratio and spectra)

hadronic flow and space-momentum correlation

HBT - space-time information

ShinIchi Esumi, Univ. of Tsukuba