  For beam energies from SPS to RHIC, the transverse energy per charged
particle, $E_T/N_{\textrm{ch}}$, saturates at a value of approximately 0.8 GeV.
A direct connection between this value and the freeze-out criterium $E/N
\approx 1$ GeV for the primordial energy and particle number in the hadronic
resonance gas model is established.
