Chemical nonequilibrium and deconfinement in 200AGeV sulphur induced reactions

We interpret hadronic particle abundances produced in S-Au/W/Pb $200A\hspace{0.5em}\mathrm{GeV}$ reactions in terms of the final state hadronic phase space model and determine by a data fit of the chemical hadron freeze-out parameters. Allowing for the flavor abundance nonequilibrium a highly significant fit to experimental particle abundance data emerges, which supports the possibility of strangeness distillation. We find under different strategies stable values for freeze-out temperature $T_f=143\mathrm{}\pm 3\hspace{0.5em}\mathrm{MeV},$ baryochemical potential ${\mu }_B=173\mathrm{}\pm 6\hspace{0.5em}\mathrm{MeV},$ ratio of strangeness $\left({\gamma }_s\right)$ and light quark $\left({\gamma }_q\right)$ phase space occupancies ${\gamma }_s/{\gamma }_q=0.60\mathrm{}\pm 0.02,$ and ${\gamma }_q=1.22\mathrm{}\pm 0.05$ without accounting for collective expansion (radial flow). When introducing flow effects which allow a consistent description of the transverse mass particle spectra, yielding $|v_c|=0.49\mathrm{}\pm 0.01\hspace{0.5em}c,$ we find ${\gamma }_s/{\gamma }_q=0.69\mathrm{}\pm 0.03,\hspace{0.5em}\hspace{0.5em}{\gamma }_q=1.41\mathrm{}\pm \mathrm{0.08.}$ The strange quark fugacity is fitted at ${\lambda }_s=1.00\mathrm{}\pm 0.02$ suggesting chemical freeze-out directly from the deconfined phase.