Strange hadrons and their resonances: a diagnostic tool of QGP freeze-out dynamics

Abstract

We update our chemical analysis of (strange) hadrons produced at the SPS in Pb--Pb collisions at 158A GeV and and present a first chemical analysis of RHIC results. We report that the shape of (anti)hyperon m_T-spectra in a thermal freeze-out analysis leads to freeze-out conditions found in chemical analysis, implying sudden strange hyperon production. We discuss how a combined analysis of several strange hadron resonances of differing lifespan can be used to understand the dynamical process present during chemical and thermal freeze-outs. In medium resonance quenching is considered.

7 pages including figures; published version with UPDATED figures, including experimental results and small numerical corrections