Particle-Type Dependence of Azimuthal Anisotropy and Nuclear Modification of Particle Production in Au+Au Collisions at √(sNN)=200 GeV
Abstract
We present STAR measurements of the azimuthal anisotropy parameter v2 and the binary-collision scaled centrality ratio RCP for kaons and lambdas (Λ+Λ¯) at midrapidity in Au+Au collisions at √(sNN)=200 GeV. In combination, the v2 and RCP particle-type dependencies contradict expectations from partonic energy loss followed by standard fragmentation in vacuum. We establish pT≈5 GeV/c as the value where the centrality dependent baryon enhancement ends. The K0S and Λ+Λ¯ v2 values are consistent with expectations of constituent-quark-number scaling from models of hadron formation by parton coalescence or recombination.
- Publication:
-
Physical Review Letters
- Pub Date:
- February 2004
- DOI:
- 10.1103/PhysRevLett.92.052302
- arXiv:
- arXiv:nucl-ex/0306007
- Bibcode:
- 2004PhRvL..92e2302A
- Keywords:
-
- 25.75.Ld;
- 25.75.Dw;
- Collective flow;
- Particle and resonance production;
- Nuclear Experiment
- E-Print:
- 6 pages, 4 figures, 1 table. As published in PRL on Feb. 2, 2004