Left panel: double ratio of the measured ${\rm K^{\pm}/\pi^{\pm}}$ \pt spectra in central \PbPb collisions and in pp collisions at \fivenn  dilated as a function of \pt by the ratio of the $\eta$ and $\rm K^{\pm}$ meson mass (see text). Right panel: measured  and parameterized $\frac{\eta}{\pi^{0}}$ ratios in hadronic collisions and central \PbPb collisions, respectively.