pid vand vin au+au collisions for √snn = 200 gev at star .pptVIP

* minibais result for centrality 0-80% * * * Na Li 25th Winter Workshop on Nuclear Dynamics Na Li 25th Winter Workshop on Nuclear Dynamics PID v2 and v4 from Au+Au Collisions at √sNN = 200 GeV at RHIC N. Li for the STAR Collaboration Lawrence Berkeley National Laboratory, Berkeley Institute of Particle Physics, Wuhan, China Outline * Na Li 25th Winter Workshop on Nuclear Dynamics Motivation Analysis Results Summary Na Li 25th Winter Workshop on Nuclear Dynamics * Motivation Formation of QGP in high-energy nuclear collisions: De-confinement Collectivity Local thermalization Important questions We study with dataset of highest statistics Na Li 25th Winter Workshop on Nuclear Dynamics * Anisotropy Parameters spatial space anisotropy momentum space anisotropy Azimuthal correlation with the reaction plane. Built up in the early stage, therefore supplies the early information of matter generated in the collision. pQCD ReCo Coalescence Hydro Motivation (cont.) * Na Li 25th Winter Workshop on Nuclear Dynamics Study the PID dependence of v2 and v4. R. S. Bhalerao et.al PLB 627, 49; Borghini and Ollitrault, PLB 642, 227 Study Number-of-Quark scaling. Range? v4/v22 : a probe of ideal hydro behavior. STAR: Phys. Rev. C 77 (2008) 54901 Na Li 25th Winter Workshop on Nuclear Dynamics * Anisotropy Parameter v2 Baryon and meson elliptic flow follow the number of quark ( Nq ) scaling. Indicates that partonic flow builds up at RHIC. STAR: Phys. Rev. C 77 (2008) 54901 How about the higher order anisotropic flow such as v4? Na Li 25th Winter Workshop on Nuclear Dynamics * Anisotropy Parameter v2 v4 Peter Kolb, PRC 68, 031902 STAR: Aihong Tang, Proc. 24th Winter Workshop on Nuclear Dynamics v4 : 4th harmonic If system reaches local thermal equilibrium, according to ideal hydro dynamic calculation, v4/v22 approaches 0.5 at hig