Quark number susceptibilities, strangeness, and dynamical confinement

We report the first results on the strange quark number susceptibility ${\chi }_s$ over a large range of temperatures, mainly in the plasma phase of QCD. ${\chi }_s$ jumps across the phase transition temperature $T_c$ and grows rapidly with temperature above but close to $T_c.$ 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.