System Size, Energy, Pseudorapidity, and Centrality Dependence of Elliptic Flow
Abstract
This Letter presents measurements of the elliptic flow of charged particles as a function of pseudorapidity and centrality from Cu-Cu collisions at 62.4 and 200 GeV using the PHOBOS detector at the Relativistic Heavy Ion Collider. The elliptic flow in Cu-Cu collisions is found to be significant even for the most central events. For comparison with the Au-Au results, it is found that the detailed way in which the collision geometry (eccentricity) is estimated is of critical importance when scaling out system-size effects. A new form of eccentricity, called the participant eccentricity, is introduced which yields a scaled elliptic flow in the Cu-Cu system that has the same relative magnitude and qualitative features as that in the Au-Au system.
- Publication:
-
Physical Review Letters
- Pub Date:
- June 2007
- DOI:
- 10.1103/PhysRevLett.98.242302
- arXiv:
- arXiv:nucl-ex/0610037
- Bibcode:
- 2007PhRvL..98x2302A
- Keywords:
-
- 25.75.-q;
- Relativistic heavy-ion collisions;
- Nuclear Experiment
- E-Print:
- Phys.Rev.Lett.98:242302,2007