Energy scan by ϕ mesons and threshold energy for the confinement-deconfinement phase transition

We argue that the ratio of ϕ mesons multiplicity over cube of the mean pT is proportional to the degeneracy of the medium produced in ultra-relativistic heavy ion collisions. The ratio extracted from the existing ϕ meson data in the energy range s=6.3-200 GeV, indicates that beyond a threshold energy sth=15.74±8.10 GeV, the medium crosses over from a confined phase to a deconfined phase.