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Quark-hadron Duality of Hadronization in Nuclei. Xin-Nian Wang LBNL. First Workshop on Quark-Hadron Duality and the Transition to pQCD Frascati, June 6-9, 2005. Quark-hadron Duality. hadrons from Mars. QCD. quarks from Venus. Quark scattering or hadron absorption?. e -.
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Quark-hadron Duality of Hadronization in Nuclei Xin-Nian Wang LBNL First Workshop on Quark-Hadron Duality and the Transition to pQCD Frascati, June 6-9, 2005
Quark-hadron Duality hadrons from Mars QCD quarks from Venus
Quark scattering or hadron absorption? e- Quark propagation and scattering, Hadronization outside the nuclei Hadronization inside nuclei Hadron absorption
Conclusions • Never promise any great ideas!
Quark Fragmentation Function q S e+e- annihilation Collinear factorization
DGLAP Evolution Splitting function
DIS off Nuclei e- Frag. Func.
Multiple Parton Scattering Formation time
Multiple Parton Scattering Collinear expansion: Generalized factorization: (LQS’94)
Collinear approximation Double scattering First term Eikonal
Modified Fragmentation Modified splitting functions Two-parton correlation: LPM Guo & XNW’00
HERMES data E. Wang & XNW PRL 2000 in Au nuclei
Conclusions • Never promise any great ideas! • Leading hadrons suppressed in DIS eA, agrees well with multiple parton scattering
Di-hadron fragmentation function h1 h2 jet Majumder & XNW’04
DGLAP for Dihadron Fragmentation h1 h1 h2 h2 h1 h2
Medium Modified Dihadron Triggering h1 D(z1,z2)/D(z1)
Higher orders or hadron absorption? h h Hadron formation time: protons
Conclusions • Never promise any great ideas! • Leading hadrons suppressed in DIS eA, agrees well with multiple parton scattering • Higher twists might be important • Hadron absorption likely at lower energies
Angular distribution of radiative gluons Induced Bremsstrahlung: Radiation in vacuum Dihadron correlation in relative transverse momentum
Jet Quenching in Heavy-ion Collisions jet1 f jet2 Azimuthal asymmetry
Abnormal angular distribution STAR PHENIX
Parton Energy Loss Quark energy loss = energy carried by radiated gluon
Conclusions • Never promise any great ideas! • Leading hadrons suppressed in DIS eA, agrees well with multiple parton scattering • Higher twists might be important • Hadron absorption likely at lower energies • Initial gluon density in Au+Au is about 30 times higher than cold nuclei • Multiple hadron correlations critical measurements
Flavor of Jet Quenching Parton recombination
A Perfect Fluid ? Hydrodynamic model with zero viscosity String theory AdS5/CFT Policastro,Son,Starinets Weakly colored Bound states
Bulk Elliptic Flow Hydro-dynamics calc. Pressure gradient anisotropy
High density at RHIC GeV for E=10 GeV Consistent with estimate of initial condition From RHIC high pT data: single & di-hadron, v2 Initial (energy) density 30 (100) times of that in a Cold Au Nucleus also consistent with hydrodynamic analysis of radial flow from
Parton Energy Loss Same-side jet profile Same-side jet cone remains the same as in pp collision Hadron rescattering will change the correlation Between leading and sub-leading hadrons
Geometry of Heavy Ion Collisions EZDC z x y Impact Parameter (b) ET Centrality of the collisions ET EZDC
No jet quenching in d+Au Initial state effect: Shadowing & pt broadening: XNW, PRC61(00)064910
Azimuthal Anisotropy II STAR preliminary out-plane 20-60% In-plane 20-60% Azimuthal Mapping of jet quenching
High pT spectra in A+A collisions pQCD Parton Model
Energy Loss of A Heavy Quark B. Zhang & XNW’03 Dead cone effect
Jet Quenching at RHIC XNW’03
Suppression of away-side jet STAR preliminary 20-60% 20-60% Di-hadron invariant mass spectra