Energy scan by $\varphi$ mesons and threshold energy for the confinement-deconfinement phase transition

Abstract

We argue that the ratio of $\varphi$ mesons multiplicity over cube of the mean $p_T$ is proportional to the degeneracy of the medium produced in ultra-relativistic heavy ion collisions. The ratio extracted from the existing $\varphi$ meson data in the energy range $\sqrt{s}$=6.3-200 GeV, indicate that beyond a threshold energy ${\sqrt{s}}_{th}=15.74\pm 8.10$ GeV, the medium crosses over from a confined phase to a deconfined phase.

Comments: Revised version to be published in Phys. Lett. B. 5 pages, 6 figures.