Post on 15-Jan-2016
description
Xin-Nian Wang/LBNL
QCD and Hadronic PhysicsBeijing, June 16-20, 2005
Xin-Nian Wang王新年
Lawrence Berkeley National Laboratory
Jet Tomography of Strongly Interacting QGP
Xin-Nian Wang/LBNL
QCD phase transition
,1
1( )
2 4
fna
QCD a a af a
L i gA m F F
22 2 23
4( )
(11 ) ln( / )sf QCD
Qn Q
Asymptotic freedom
Confinement
412
sa aT F F B
scale anomaly (break scale invariance)
1/ 40.72cT B
Xin-Nian Wang/LBNL
Lattice QCD results
MeVTc 8170 3/ 3.06.0 fmGeVc
F. Karsch ‘2001
Xin-Nian Wang/LBNL
Medium Response
41( ) (0) ( )
4iq x em emW q d xe A j j x A
1
2
2
2 2
( )
( )1
B
B
DIS
q qW g
q
p q p qp q p q
F
xq
Fp q q
x
qp
qxB
2
2
Dynamic System: Photon or dilepton emission (McLerran & Toimela’85)
J/ suppression (Matsui & Satz’86)
( ) ( )emj x j x QCD Response: Parton scattering (Gyulassy & XNW’92)
Xin-Nian Wang/LBNL
Jet Quenching & Modified Fragmentation
e-
, )) (( ,( )qh
q h hHdW
d f x p q Dxd
zz
x
2 122
40
( , ) ( , )2
h
Q
S hq h h L q h
z
zd dzD z Q z x D
z z
2 ( , ) 21( , ) (virtual)
(1 ) ( )
Aqg L A S
L Aq c
T x x Czz x
z f x N
Guo & XNW’00
Xin-Nian Wang/LBNL
Non-Abelian LPM Effect
_2 1(
1 2 1 2
2)
1
( , ) (0) ( ) ( ) ( )2 2
( ) ( )1 1
B
L Lix p y ix
ix p yA
y
g
y
q L
pe
dyT x x dy dy e A F y F y y A
y y ye
Two-parton correlation:
Landau- Pomeranchuck-Migdal interference:
i
j
22 2
12
1
/( ) ( )
4ij fii i
i i
L
i
k k v k k vd I e
d d k v ke
v
Formation time
21
2 (1 )T
fLx p q z z
Xin-Nian Wang/LBNL
Quadratic Nuclear Dependence
0 22/3~ ( )[1 ( ) ]S
S D q B T TAf x C x G xQ
A
2~ ( )s
S q BAf x
4/34
~ ( ) ( )sD q B s T TA f x C x G x
3/1
22 LPM
A
Q
Xin-Nian Wang/LBNL
HERMES data
2 20.00065 GeVsC
E. Wang & XNW2000
Xin-Nian Wang/LBNL
Parton Energy Loss
2 1 22
2
2 2 20 0
( ,(1 )
(
1 )
)
Q Aqg L
AA s
gq
TcT T T
Czz
Td dz
N
x x
f xk
0
320( )(
2ln)a
R
A s
EE C C d
BDPMGyulassy Vitev LevaiWang & WangWiedemann; Zakharov
Quark energy loss = energy carried by radiated gluon
2( , )~ 1 cos
( )( )
Aqg L
gAq f
g
ydy
T xy
x
f x
2( ) ~s gxG x
Xin-Nian Wang/LBNL
HERMES data
2 20.00065 GeVsC
0.5 GeV/fmdE
dx
in Au nuclei
E. Wang & XNW2000
Xin-Nian Wang/LBNL
Jet Quenching at RHIC
NNAB
ABAB
NR
binary
( ) ( )D z D z
Xin-Nian Wang/LBNL
Geometry of dense matter
Non-central collisions
Azimuthal asymmetry
0 1 2(1 cos 2 cos 2 )chdNN v v
d
jet
jet
Xin-Nian Wang/LBNL
Dihadron Correlation
pTtrig=4-6 GeV
pT=2-4 GeV
Pedestal&flow subtracted
Pedestal&flow subtracted
trigger
Xin-Nian Wang/LBNL
Away-side suppression
0
13.8 3.9 GeV/fmdE
dx
cold matter
0.5 GeV/fmdE
dx
trigger
Xin-Nian Wang/LBNL
Elliptic flow of a perfect fluid
2cos2 v
Pressure gradient anisotropy
0T
Hydrodynamiccalculation with
=0
Xin-Nian Wang/LBNL
Jet Remnants
2
2 (1 )f
T
Ez z
k
2
2 2 2 2
11
( )f
R
g
T T T
dNe
dzdk k k
Induced Bremsstrahlung:
M
Cherenkov radiationPedestal&flow subtracted
Xin-Nian Wang/LBNL
3-D Tomography
4 ( )qq
pP
E E m
Global polarization w.r.t.Nuclear reaction plane
x
2 zy z
dpL x p x
dx
Z.-T. Liang, XNWPRL 94 (2005)102301
Xin-Nian Wang/LBNL
Summary
• Discovery of Jet Quenching at RHIC proves that a interacting dense matter is formed: Opaque to jets
• Dense matter at RHIC is 30 times higher than cold nuclei, energy density is 100 times higher
• Collective behavior: Hydrodyamic limit strongly interactive QGP
• Jet tomography a useful and power tool for studying properties of dense matter– Heavy quarks, dihadron correlation, angular
distribution, flavor dependence …
Xin-Nian Wang/LBNL
Xin-Nian Wang/LBNL
Xin-Nian Wang/LBNL
Angular distribution of radiative gluons
2
2 2
1 (1 ) 1
2g S
FT T
dN zC
dzdk z k
1gdN
d
max
(1 / )
2g
g
E
R
Radiation in vacuum
2
2 (1 )f
T
Ez z
k
22 2
2 2 2 2
1 (1 ) 11
( )f
R
g A S
T c T T
dN C zcmR e
dzdk N z k k
Induced Bremsstrahlung:
Further interaction of the radiated gluons with the medium?
Xin-Nian Wang/LBNL
Di-hadron fragmentation function
1 2 1 2 1 2 1 2( , ) 0 (0) , , ( ) 02q h h q h h h h q
S
D z z Tr p p S p p S y
h1 h2
jet
Majumder & XNW
Xin-Nian Wang/LBNL
Modification of the dihadron distribution
Pedestal&flow subtracted
STAR preliminary
Effect of longitudinal flow
C. Salgado
z
Xin-Nian Wang/LBNL
Sonic Boom
cos M sc
M Trigger
Casalderrey-Solana, Shuryak and Teaney
Linearize disturbance
Xin-Nian Wang/LBNL
Future of Jet quenching
STA
R p
relim
inar
y
STA
R p
relim
inar
y
+jet correlation in Au+Au in run4?
More accurate determination of initial Et
Xin-Nian Wang/LBNL
Modification for Heavy Quarks
2
1
1/ (1 ) / 2Hf
f z M zq
(1) Slow clock for formation time
Djordjevic & GyulassyZhang & XNWArmesto,Dainese, Salgado & Wiedemann
(2) Color factor
(3) Dead cone effectEQ<Eg, Eq
Zhang & XNW
Xin-Nian Wang/LBNL
Energy Dependence of quenching
D. d’Enterria, Hard Probes 2004
0 20
1( ) ch
gA
dN
R dy
Xin-Nian Wang/LBNL
Effect of non-Abelian energy loss
Eg=Eq
Eg=2Eq
Qun Wang & XNW nucl-th/0410079
EskolaHonkanenSalgadoWiedemann
Fixed pT=6 GeV
Xin-Nian Wang/LBNL
No suppression in d+Au
STAR PHENIX
Xin-Nian Wang/LBNL
High pt spectra in Au+Au
( ) ( )D z D z
H. Zhang,E. WangJ. Owens, XNW 2005
0
( )
Xin-Nian Wang/LBNL
High pt spectra in pp collisions
H. ZhangJ. OwensE. WangXNW2005
Xin-Nian Wang/LBNL
Charm quark
Large charm quarkSuppression?
Hadronic scattering?
Xin-Nian Wang/LBNL
Parton recombination
Hwa; Fries
Particle or parton correlations are not trivial