Abstract
New measurements are presented for charged hadron azimuthal correlations at midrapidity in collisions at and 200 GeV. They are compared to earlier measurements obtained at and in collisions at . Sizeable anisotropies are observed with centrality and transverse momentum () dependence characteristic of elliptic flow (). For a broad range of centralities, the observed magnitudes and trends of the differential anisotropy, , change very little over the collision energy range , indicating saturation of the excitation function for at these energies. Such a saturation may be indicative of the dominance of a very soft equation of state for .
- Received 19 November 2004
DOI:https://doi.org/10.1103/PhysRevLett.94.232302
©2005 American Physical Society