Event anisotropy image at STAR Original Research Article

Collective flow reflects the dynamical evolution in high-energy heavy ion collisions. In particular, the elliptic flow reflects early collision dynamics [STAR Collaboration, J. Adams et al., Nucl. Phys. A 757, (2005) 102]. We present a systematic analysis of elliptic flow (ν2) for identified particles measured in Au + Au and Cu + Cu collisions at View the MathML source. Number of quark scaling is tested in the intermediate pT region and in the smaller system (Cu + Cu ). The Cu + Cu collisions results are compared with those from ideal hydrodynamic model calculations.