Continuum limit of quark number susceptibilities

We report the continuum extrapolation of quark number susceptibilities in quenched QCD. Deviations from ideal gas behavior at temperature T increase as the lattice spacing is decreased from 1/4T to 1/8T. The continuum extrapolation of the measured susceptibilities is 25% lower than the ideal gas values, and also 15% below the hard thermal loop (HTL) results. The off-diagonal susceptibility is several orders of magnitude smaller than the HTL results. We verify a strong correlation between the lowest screening mass and the susceptibility. We also show that the quark number susceptibilities give a reasonable account of the Wroblewski parameter, which measures the strangeness yield in a heavy-ion collision.