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ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 1
Collective Expansion of QGP
ShinIchi EsumiUniv. of Tsukuba, Inst. of Physics
1. Thermal, chemical freeze-out2. Radial, elliptic expansion3. Jet modification
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 2
QGP
Hadron
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 3
t
z
SPS (17GeV)SPS (17GeV)
LHC(5500GeV)LHC(5500GeV)
AGS (4GeV)AGS (4GeV)
RHIC(200GeV)RHIC(200GeV)
BNLBNL CERNCERN
thermal freeze-out
thermal freeze-outchemical freeze-out
chemical freeze-outquark gluon plasma
quark gluon plasma
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 4
chemical freeze-out
the end of inelastic interactions, when the particle species and ratios are frozen
Phys. Rev. C 73(2006) 034905
‘net’ proton dN/dy
AGS
SPS
RHIC 62
RHIC 200
LHC 5500
BRAHMS preliminary
charged particle dN/dy
PHOBOS
extrapolated to LHC
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 5
locally thermalcollective expansionradial flow
T eff = T fo +
0.5 m
v 2 thermal freeze-out
the end of elastic interactions, when the momentum spectra are frozen
SPS Pb+PbCentral
RHIC Au+Au Central
RHIC Au+AuPeripheral
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 6
AuAu Central charm hadron
AuAu Central , K, p
AuAu Central strangeness hadron
SQM06, Yifei Zhang
nucl-ex/0307024
SQM06, Yifei Zhang
History of
hadron freeze-out
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 7
x
z
sideward flow (v1)
x
z
y
Reaction Plane (R.P.)
elliptic azimuthal event anisotropylow pT high pT
particleR.P. (rad)
x
y
elliptic flow (v2)
initial geometryfinal momentum anisotropy
anisotropic flow
dN/d
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 8
System size dependence of v2
0.2<pT<1.0 [GeV/c]
Dividing by Npart1/3
: relate this with expansion time
v2 vs. Npart v2/ vs. Npart
v2/ (Au+Au) = v2/ (Cu+Cu)v2/eccentricity is scaled by Npart
1/3 and not dependent on the collision system.
V2//Npart1/3 vs. Npart
PHENIX PRELIMINARY
Systematic errors from eccentricity is not included here.
Maya Shimomurawill talk today!
Hiroshi Masui (also talks today!) will be discussing similar data but in a different way from STAR.
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 9
Phys. Rev. Lett. 99, 052301 (2007)
STAR preliminary
QM06
particle identified v2 at RHIC
Number of constituent quark scaling in hadron v2 as well as multi-strange baryon v2: v2 is already established during the quark phase before the hadronization. This seems to be true even for heavy quark like charm.
QM08: A.Dion
Hadron
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 10
SQM06, Jin-Hui ChenQuark momentum distribution(from hadron momentum distribution and quark coalescence pictureespecially using early freeze-out multi-strangeness hadrons)
His talk today!
* Similar mT spectra between strange and light quarks, but a slight ”effective mass” dependence which may come from radial flow of partonic stage.
* There seems to be centrality dependence, which maybe different between strange and light quarks. (We should see the build up of patonic collectivity.)
s = (sss) / (ss) compared with s = {(sss)}1/3 and/or s = {(ss)}1/2
* q = (qss) / (ss) (or s from above) compared with q from late freeze out charged hadrons (,K,p) to see the additional radial flow from hadronic stage.
)2/(
)3/(
)2/(
)3/(
T
T
T
T
p
pd
p
ps
φ
φ
=
=
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 11
AGS RHIC
common initial source geometry from centrality measurement
final source geometry from HBT measurement
final particle emission anisotropy from v2 measurement
source geometry from HBT (also tells us the history of expansion)
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 12
RHIC 200GeV SPS 17GeVRHIC 62GeV
PHENIXnucl-ex/0611019
S.Kniege, ISMD 2007
jet
p p
Au Au
Jet suppression modification with 2-particle correlation
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 13
System Size and Beam Energy Dependence of Jet Shape
nucl-ex/0611019
No energy dependence (62 ~ 200GeV)Rapid change between Npart = 0 ~ 100Almost no change above Npart > 100
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 14
arXiv:0801.4545
Transverse Momentum (Trigger, Associate) Dependence of Jet Shape
Suppression in both near/away side peak at high pT
Enhancement in near side peak at low pT
Development of away side shoulder at low pT
No pT dependence of shoulder peak position, also in 3-p correlation, both results support mach-cone emission.
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 15
p+p, peripheral Au+Au central Au+Au PHENIX QM08
d+Au, 200 GeV STAR QM06
(rad)
RidgeRidge
“jet”
Au+Au, 200 GeV
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 16
QM08 PHENIX
Centrality Dependence of Ridge and Shoulder Yield and <pT>
Both ridge and shoulder yields increase linearly with Npart. Similar (flat) centrality dependence on inverse slope parameter for both ridge and shoulder.Jet (p+p) like pT shape is harder than ridge, ridge is harder than shoulder, shoulder is similar to inclusive.
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 17
STAR Preliminary
TInclusive ~ TShoulder ~ TRidge < TJet
QM06
QM08
ridge
jet
inclusive
< <
Both ridge and shoulder <pT> are almost independent with centrality and trigger pT selections.It’s just like a bulk matter… suspicious on BG(bulk) subtraction… but this is what we see…
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 18
arXiv:0712.3033
Near/Away-side B/M ratio increases in centralAway-side B/M ratios approach inclusive valuesIncompatible with in-vacuum fragmentation
Hadron trigger with identified associate Baryon/Meson --- Mach-cone property ---
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 19
Ridge vs. Inclusive
STAR Preliminary
Jet Cone vs. Inclusive
STAR Preliminary
QM08: Bedanga Mohanty
QM08: Paul Sorenson
STAR PreliminaryAu+Au 200 GeV
20-60%
3< pTtrig < 4 GeV/c
pTasso : 1.0- 1.5 GeV/c
sys. error v2{RP}
sys. error v2{4}
20-60%
QM08: Aoqi Feng
Several Ridge properties
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 20
yt1
yt2
transverse correlations
yt ~ ln(pt)
0.5
1
2
34
pT (Gev/c)
STAR Preliminary
2-particle correlation without high pT trigger selection
200GeV p+p
hard component
ηΔ
φΔ
soft component
ηΔ
φΔ
Longitudinal Fragmentation (“strings”) 1D Gaussian, US pairsHBT peak at origin, LS pairs
Minijets 2D Gaussian at origin, away-side peak actually cos(φΔ)
J of Phys: Conf 27 (2005) 98
These structures define minijet cor
relations
M. Daugherity, QM08
axial correlations
ηΔ
φΔ
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 21
longitudinal fragmentation1D gaussian
HBT, res., e+e-2D exponential
Minijet Peak2D gaussian
Away-side -cos(φ)
ΔηΔφ
Elliptic flowcos(2φΔ)
1.2M minbias 200 GeV Au+Au eventsIncluded all tracks with pT > 0.15 GeV/c, || < 1, full φ
84-93%
28-38%
75-84%
19-28%
65-75% 55-65% 46-55%
9-19% 5-9% 0-5%
M. Daugherity, QM08
STAR Preliminary
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 22
Centrality
200 GeV62 GeV
STAR Preliminary STAR Preliminary STAR PreliminaryPeak Amplitude Peak η Width Peak φ Width
HIJING 1.382 default200 GeV, quench off
binary scaling assumptionin Kharzeev and Nardi model
data - fit (except same-side peak)
Shape changes little from peripheral to the transition
83-94% 55-65%
ηΔ width
STAR Preliminary
STAR Preliminary
Large change within ~10%
centrality
46-55%
STAR Preliminary
Smaller change from transition to most central
0-5%
STAR Preliminary
QM08 STARE
xtracted 2-D near-side G
aussian param
eters are shown. T
he strong
width change vs centrality should h
ave a relation to the ridge formatio
n.
longitudinal (densitycorrelation length
Kensuke Homma, tomorrow!
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 23
3<pTtrig<4GeV/c & 1.0<pT
asso<1.5GeV/c 20-60%STAR
= associate - trigger (rad)
Jet modification and geometry(and v2)
QM08: STAR, PHENIX
QM04: STAR
Mach-cone shape depends on R.P. angle.Mach-cone is a source of of v2
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 24
STAR Preliminary
Rid
ge
Jet
3<pTtrig<4, 1.5<pT
trig<2.0 GeV/c
QM08 STAR
STAR
(rad)
RidgeRidge
“jet”Au+Au, 200 GeVRidge/Cone and
geometry (v2)
Ridge shape depends on R.P. angle.Ridge is a source of of v2
Jet does not depends on itJet reduces v2
Jet
Rid
ge
Shou
lder
(co
ne)
Hea
d (
)Rid
ge
Shou
lder
(co
ne)
v2
v2
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 25
(rad)
PYTHIA p+ptrigger
near side
away sidey
x
(1) away side of a back-to-back(b-t-b) jet is wider in than in (2) If there are two parallel b-t-b jets, away side of one b-t-b jet can be
near side of the another b-t-b jet.(3) Suppression as well as modification of b-t-b jet would depend on re
lative angle w.r.t. almond geometry, we know this from v2 measurement and believe this is the major source of v2 at high pT .
(4) Therefore, there should be inter b-t-b jets correlation give by the geometry from (3), this could make near side ridge like effect, especially if the effect (3) has shaper dependence than v2(=cos2x).
(5) We always measure inclusive v2, which includes the effect (3). Therefore any modification which could generates the elliptic anisotropy would be included in the measured v2 .
(6) We subtract BG contribution with this v2 from (5) by maximizing BG contribution assuming zero jet yield at minimum at any d.
(7) If near and away side jets overlap each other, this subtraction underestimates the jet yield and can change the extracted jet shape.
(8) If you extract angular dependence of jet w.r.t. R.P., the results will easily be affected by the choice of v2 from (5).
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 26
(1)
(2)
(3)
(4)
(2)
(3)
(4)
(1)
Trigger
particle
x(R.P.) x(R.P.)
yy
(2)Trigger
particle
ASSO.TRIG.
associate particle direction at
same || w.r.t. trigger particle
but with different arrow length
associate particle direction at
same || w.r.t. red dashed line
but with different arrow length
In order to study the jet modification (mach-cone, ridge) and it’s relation with almond geometry in more detail…
with and without R.P. aligned event mixing
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 27
Summary
(1) Thermal, chemical freeze-outTch ~ QGP phase boundaryHistory of thermal freeze-out
(2) Radial, elliptic expansionQuark phaseQuark coalescenceHistory of radial, elliptic expansion
(3) Jet suppression, modificationQGP matter propertyrelation between v2 and modificationsubtraction of flow, which includes the modification
jet-jet correlation via reaction plane (part of v2)
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 28
R.P.
(1)(2)
(3)
(4)
(5)
(6)(7)
(8)ave (1)~(8)
ave (1),(8) ave (2),(7) ave (3),(6) ave (4),(5)
(1) (2) (3) (4)(8) (7) (6) (5)
Pure Flow Simulationwith trigger angle selection w.r.t. R.P.with/without R.P. aligned event mixing
wit
hout
R.P
. ali
gned
eve
nt m
ixin
gw
ith
R.P
. ali
gned
ev
ent m
ixin
g
(1) (2) (3) (4)(8) (7) (6) (5)
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 29
V4V4/(nq)2
M. Issah, QM08
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 30
K. Miki, QM08
PHENIX preliminary
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 31
STAR Preliminary
(1-2)/2
(1-2)/2
STAR Preliminary
Cone angle (radians)
pT (GeV/c)
jet
p p
Au Au
d+AuCollisions
Au+Au Central 0-12%
3-particle correlation “12 vs 13”
*=
*=
PHENIX Preliminary PHENIX Preliminary
Cone like Jets
Deflected Jets
No pT dependence, too.
Both measurements preferMach-cone scenario.
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 32
Away RegionShoulder Region Head RegionShoulder Region
Near Region
A Large BG Subtraction with v2 like Flow Shape
regiondouble peak region
Same Side Far Side
Description of Jet Shapewith Several Key Words
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 33
PRL91(2003)0723042<pT
Asso.<pTt 4< pTTrig.< 6 GeV/c
PRL95(2005)1523010.15<pT
Asso.<4 4< pTTrig.< 6
GeV/c
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 34
0-20% Au+Au 20-40% 60-92%
Solid points are Au+Au, open points are p+p, red/blue colors show systematic errors.
More central arXiv:0801.4545
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 35
p+p vs Au+Au cent 60-92%
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 36
p+p vs Au+Au cent 0-20%
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 37
arXiv:0801.4545
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 38
arXiv:0801.4545
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 39
arXiv:0801.4545
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 40
Jet + Flow (Raw) Jet (Flow subtracted)
M. P. McCumber, QM08
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 41
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 42
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 43
arXiv:0801.4545
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 44
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 45
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 46
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 47
PHENIX preliminary
Identified 0 trigger with associate hadron
Width does not change with centrality similar to charged hadron triggered case.
7-9 (X) 1-20-20%
7-9 (X) 4-50-20%
7-9 (X) 4-520-40%
7-9 (X) 4-540-60%
7-9 (X) 4-560-90%
7-9 (X) 6-840-60%
QM08 PHENIX
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 48
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 49
1/N
trig
dN
/d
(A.U
.)
pT, photon GeV
Per-
Tri
gg
er
Yie
ld (
A.U
.)
Run 6 p+p @ 200 GeV
0
Run 7 Au+Au @ 200 GeV, cent=0~20%, preliminary
Direct trigger with associate hadronQM08 PHENIX
p+p: C
onsistent with trigger photon carr
ying the full jet energy, away side jets ar
e similar betw
een 0 and
triggers.
Need m
ore studies and statistics for A
u+A
u case.
Run 4/5 p+p/Au+Au @ 200 GeV
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 50
84-93%
28-38%
75-84%
19-28%
65-75% 55-65% 46-55%
9-19% 5-9% 0-5%
84-93%
28-38%
75-84%
19-28%
65-75% 55-65% 46-55%
9-19% 5-9% 0-5%
Fit residual = data - model
Fit model
ATHIC2008, 14/Oct/2008, Tsukuba, Japan ShinIchi Esumi, Univ. of Tsukuba, Japan 51