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Effect of parton cascade to the medium. Hanlin Li IOPP, CCNU, Wuhan Fuming Liu IOPP, CCNU, Wuhan Xin-Nian Wang LBNL, USA Yan Zhu IOPP, CCNU, Wuhan. QNP, Beijing , September 21 - 26, 2009. OUTLINE. Introduction Preliminary results Elastic energy loss
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Effect of parton cascade to the medium Hanlin Li IOPP, CCNU, Wuhan Fuming Liu IOPP, CCNU, Wuhan Xin-Nian Wang LBNL, USA Yan Zhu IOPP, CCNU, Wuhan QNP, Beijing , September 21-26, 2009
OUTLINE • Introduction • Preliminary results • Elastic energy loss • Medium modification caused by jet propagating • Conclusions and Outlook
Introduction — jet quenching • Jet quenching is a good probe of sQGP. • Suppression of High PT hadrons. • It’s also important to study the modification of medium due to jet propagation. • Azimuthal angle correlation caused by jet medium interaction. • Several models: • Putting a source current in hydrodynamic (Chaudhuri and Heinz,2006); • Markovian parton scattering (MPS) model (Charles B. Chiu and Rudolph C. Hwa,2006). • ……
Our approach — Parton cascade simulation based on Boltzmann Eq. By now only elastic collisions are considered. where and
More useful formulae • Elastic collision rate: • Energy distribution of thermal parton: • Interaction amplitude: • Interval between successive collisions : Gyulassy and Wang, Nucl.Phys.B420,583
E1=20GeV Test our MC with numerical integration Set jet moving along z-axis • Energy distribution of produce partonsfrom single scattering for different energy of jet E1. • Angle (theta=ATAN(pz/E) ) distribution of produce partonsfrom single scattering for different energy of produce particle.
Theory (X.N. Wang,Phys.Rept.280:287-371.) w. s.a.a. w/o. s.a.a. Elastic energy loss for qq collision
Modification of medium by propagating jet Jet moves along z-axis. t=2fm/c r=sqrt(x2+y2)
pro. Azimuthal angle distribution —singlescattering Jet moves along z-axis. • Double-peak appears in single scattering. • Azimuthal angle distribution is energy dependence. • Double-peak appears in single scattering. • Azimuthal angle distribution is energy dependence. Ф=ACOS(pz/sqrt(pz2+px2))
t=15fm/c t=4fm/c t=1fm/c Azimuthal angle distribution—multiple scattering • Double-peak at the early time as single scattering • Uniform distribution after enough time. • Double-peak disappears due to the interaction of associate partons.
Conclusions and Outlook • A parton cascade simulation has been construced based on Boltzmann eq.. • Elastic energy loss has been investigated. Strict calculation shows a lower energy loss than that in previous work. • Cone structure of produced parton can be formed when jets propagate in the medium. • The azimuthal angle distribution of produced partons depends strongly on their energy and the medium size. • More realistic medium will be used. • Inelastic collision(2 3) will be included.
Thanks for your attention!
Azimuthal angle correlation —singlescattering Jet move along z-axis. Ө=ATAN(pz/E) Azimuthal correlation is energy dependence.
Multiple scattering exclude scattering among thermal partons