Strangeness Enhancement in Cu+Cu and Au+Au Collisions at \sqrt{s_{NN}} =   200 GeV
  We report new STAR measurements of mid-rapidity yields for the $\Lambda$, $\bar{\Lambda}$, $K^{0}_{S}$, $\Xi^{-}$, $\bar{\Xi}^{+}$, $\Omega^{-}$, $\bar{\Omega}^{+}$ particles in Cu+Cu collisions at \sNN{200}, and mid-rapidity yields for the $\Lambda$, $\bar{\Lambda}$, $K^{0}_{S}$ particles in Au+Au at \sNN{200}. We show that at a given number of participating nucleons, the production of strange hadrons is higher in Cu+Cu collisions than in Au+Au collisions at the same center-of-mass energy. We find that aspects of the enhancement factors for all particles can be described by a parameterization based on the fraction of participants that undergo multiple collisions. 
STAR Collaboration: H. Agakishiev, M. M. Aggarwal, Z. Ahammed, A. V.   Alakhverdyants, I. Alekseev, J. Alford, B. D. Anderso...
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