System and Energy Dependence of Strangeness Production with STAR

Abstract

The yields and spectra of strange hadrons have each been measured by STAR as a function of centrality in √ s NN = 200 GeV AuAu collisions. By comparing to pp and dAu at √ s NN = 200 GeV and in AuAu at √ s NN = 62 GeV the dependence on system size and energy is studied. Strange resonances, such as Σ(1385) and Λ(1520), are used to examine the dynamical evolution between production and freeze-out for these systems. Particle production is investigated by comparison to thermal models, which assume a scaling of the yield with N part . Our hyperon measurements in AuAu indicate that N bin may be a more appropriate scale for the strangeness correlation volume. Thus canonical suppression can not be simply parameterized with the geometrical overlap volume but will depend on the individual quark content of each particle. This theory is tested by comparing the data from different collision systems and centralities.

Partonic Flow andϕ-Meson Production inAu+AuCollisions atsNN=Abelev1, Aggarwal2, Ahammed3 et al. 2007Phys. Rev. Lett.1844600View full textAdd to dashboardCite

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