RHIC能区的集体流和能量扫描 - WebHome Main HEPG.ppt

RHIC能区的集体流和能量扫描 马余刚 中国科学院上海应用物理研究所 Outline: Flow Introduction Results (1): Flow measurements at RHIC Results (2): Flow Theory Summary Outlook Longitudinal scaling for v1 Low pt: mass splitting High Pt region: non-flow effect, such as partonic Eloss induced correlation Exploring the non-flow in elliptic flow Scaling generally holds in Cu+Cu at 200GeV. Some deviation at more peripheral collisions. pT 2 GeV/c Smaller v2 for heavier hadrons as expected from hydrodynamics. Sizable v2(Ξ) even in small system Ideal hydro fails to reproduce the data Fluctuation of v2? Viscosity ? Incomplete thermalization ? v2 in Cu + Cu (Au +Au) at 200 and 62.4 GeV are comparable within statistical errors Centrality dependence of v2 Pseudo-rapidity dependence of v2 Ideal Hydro Limit Even in central Au + Au collisions, fitting results indicate that the system is still away from hydro limit most perfect liquid in the world? v4/v22 – An Independent Test Similar scaling was predicted in Fermi energies: nucleon number scaling v4/v2^2 scaling Light Nuclei v2 at STAR Heavy Q elliptic flow J/ψ flow : possible test of regeneration Electrons from open c and b semileptonic decays show nonzero elliptic flow J/ψ regenerated from c quarks should inherit their flow Flow of directed photons shear viscosity effect on v2 difference about bulk-viscous effect on v2 Heavier Q flow Resonance recombination model + Langevin simulation gives good description to spectra and NCQ scaling for phi and J/Psi. Charm flow from parton transport model Single electron v2 Hirano et.al. can describe RAA but not v2 for single electrons with a relativistic Langevin equation + hydrodynamics. The reason is unclear and it needs further studies. IV: Summary The flow is measured plentifully at RHIC in the past decade, NCQ scaling studied works in lower energy, smaller system and at forward region. The new matter created at RHIC is the most perfect liqui