Download - Quark Matter 2005, Budapest
Quark Matter 2005, Budapest
Xin-Nian WangLawrence Berkeley National Laboratory
Jet and Leading Hadron Production
• Asymptotic freedom
• Scale anomaly
• Phase transition
Asymptotic Freedom and QCD
22 2 23
4( )
(11 ) ln( / )sf QCD
Qn Q
412
sa aT F F B
1/ 40.72cT B
David J. Gross H. David PolitzerFrank WilczekNobel Prize in Physics 2004
Hard processes in heavy-ion collisions
q
q
leadingparticle
leading particle
pQCD
H. Zhang,J. Owens, E. Wang XNW, in preparation
Before the Beginning…
Single Spectra Suppression
XNW and M. GyulassyPhys. Rev. Lett. 68, 1480 (1992)
ET
PHENIX
Non-suppression in p+A
XNW, Phys. Rev. C 61, 064910 (2000) [hep-ph/9812021]
PHENIX
Azimuthal Anisotropy
XNW Phys. Rev. C 63, 054902 (2001)Gyulassy, Vitev & XNW Phys. Rev. Lett. 86, 2537 (2001)
STAR
Suppression of Back-side Correlation
Pedestal&flow subtracted
STAR, Phys. Rev. Lett. 90, 082302 (2003)
Modified Fragmentation
2 ( , ) 21( , ) (virtual)
(1 ) ( )
Aqg L A S
L Aq c
T x x Czz x
z f x N
Guo & XNW’00
( )( ) ( ) ( )D zz DD z D z
2 122
40
( , ) ( , )2
h
Q
S hq h h L q h
z
zd dzD z Q z x D
z z
DGLAP-like
Parton Energy Loss and QGP
2 111 2 2 1 1), ) ( )( ( L LA ix p y ix
gp
Ly
qT x x dy F ydy eF ey
Gluon density correlation:
0
320( )(
2ln)a
R
A s
EE C C d
BDPM; Gyulassy Vitev LevaiWang & XNW; Wiedemann; Zakharov
LPM interference
pQCD Analysis of Jet Quenching
2 2 2 2 21 2 1 22
( ) ( )ABA B a a b b
abcdT
dK d b d rd r t r t r dx d k dx d k
dyd p
/ // 1 2( , , ) ( , , )1
( )aa A a a
b ch
db b cb B c
c
f x k r f xdt z
k zd
Dr
Parton distr. in nuclei & pT broadening Modified Frag. Fun.
E. Wang & XNW (2002), XNW (2004)Gyulassy, Levai & Vitev (2002)Eskola, Honkanen, Salgado & Wiedemann (2005)Q. Wang & XNW (2005)Turbide, Gale, Jeon & Moore (2005)Dainese, Loizides & Paic (2005)…
Jet Quenching at RHIC
0
13.8 3.9 GeV/fmdE
dx cold matter
0.5 GeV/fmdE
dx
0
320( )(
2ln)a
R
A s
EE C C d
30( ) 30 fm
XNW, PLB595(04)165.
LO analysis,
Energy Dependence of Jet Quenching
D. d’Enterria, Hard Probes 2004
63 GeV
XNW, PLB579(2004)299
Effect of non-Abelian energy loss
Eg=Eq
Eg=2Eq
Q. Wang & XNW nucl-th/0410079
Effects in heavy/light hadron ratio– Armesto, parallel 3c
pT=6 GeV
q=0.9 0.1
EskolaHonkanenSalgadoWiedemann
Nuclear Size Dependence
0
320( )(
2ln)a
R
A s
EE C C d
Sensitivity of RAA
•Cronin effect
•Slope of the jetspectra
•E-dependence ofthe energy loss
Gyulassy & VitevEskola,HonkanenSalgado,Wiedemann
Back-2-back Dihadron Correlations
Pedestal&flow subtracted
/( )
/
( ) ( )
( )
asso trigtrig T T
AA T T trigT
trig assoT T
TT T T
trigT
TT T
d dp dpD z p
d dp
d p pdE D D
dE E E
d pdE D
dE E
ET
= STAR preliminaryMajestero
XNW, PLB595(04)165.
Modified Dihadron Fragmentation
h1h2
h1h2
h1
h2
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’04,05Majumder, parallel 3b
Modified Dihadron Fragmentation
D(z1,z2)/D(z1)Triggering h1
Hermes Preliminary
Majumder & XNW nucl-th/0412061 E. Wang & XNW, PRL89 (2002) 162301
Pedestal&flow subtracted
Majumder, parallel 3b
Soft hadrons rings
PHENIX
Stoecker’04Casalderrey-Solana,Shuryak & Teaney ‘04Casalderrey-Solana (parallel 3b)
M
1cos M
sc
Shock wave?
LPM & Angular Correlation
2
2 2
1 (1 ) 1
2g S
FT T
dN zC
dzdk z k
Radiation in vacuum
2
2 4
11 f
R
g
T T
dNe
dzdk k
2
2 (1 )f
T
Ez z
k
Formationtime
[ , ]Tk kMultiple Scattering in QCD
max
2
gR
LPM & Cherenkov-like Bremsstrahlung
2
2 2 2
11
[ (1 ) ( )]f
R
g
T T
dNe
dzdk k z k
2
2 (1 )
(1 ) ( )fT
Ez z
k z k
J. Ruppert & B. Muller PLB619(2005)123.Dremin, JETP(1979), hep-ph/0507167Dremin (parallel 10a)
2 20 ( ), Re ( ) 0k k k k
Majumder & XNW nuth-0507063
2 1cos
( )c
zz
k
2
max (1 ) ( )Tk z k 20( ) 1 ( ) /k k k Dielectric constant
Resonances in QGP above Tc?
J/survives at T=1.6-2 Tc
Asakawa &Hatsuda ’04S. Datta, et al ‘04
F. Karsch & Laermann ‘03
Could there be other resonances?
Shuryak & Zahed ‘04
Lee, Mocsy (parallel 10c); Mannarelli, Petreczky (parallel 7a)
Dielectric Constant in QGP
Strong p-dependence Cherenkov angle
Koch, Majumder & XNW’05See Majumder (parallel 3b)
1cos
( )c
p
Future of Jet Quenching I
• No-trigger bias– Initial energy
– Surface emission
– Correlation background due to v2
XNW, Huang & Sarcevic,PRL77(96)231-jet Events
Future of Jet Quenching II
• Heavy quark jet quenching– Djordjevic, Rapp, Teaney (parallel 5b)
– B. Zhang (parallel 5a)
• Parton recombination at intermediate pt– Ko (parallel 2b), Hwa (parallel 3a),
E. Wang (parallel 3c)
• 3D jet tomography– Adil (parallel 3a)
• Incorporate dynamic evolution of bulk matter
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
• Jet tomography a useful and power tool for studying properties of dense matter– Heavy quarks, dihadron correlation, angular
distribution, flavor dependence …
• Soft hadron correlation Cherenkov radiation dielectric property of the QGP at RHIC
Back-up I
Jet Quenching Tomography