Quark number susceptibilities, strangeness, and dynamical confinement

We report the first results on the strange quark number susceptibility χₛ over a large range of temperatures, mainly in the plasma phase of QCD. χₛ jumps across the phase transition temperature Tc and grows rapidly with temperature above but close to Tc. For all quark masses and susceptibilities in the entire temperature range studied, we find a significant departure from ideal-gas values. We also observe a strong correlation between these quantities and the susceptibility in the pseudoscalar channel, supporting ideas of ``dynamical confinement'' in the high temperature phase of the QCD plasma.