Can phi mesons give an answer to the baryon puzzle at RHIC?

The PHENIX experiment at RHIC has observed a large enhancement of baryon and anti-baryon production at p(T) approximate to 2-5 GeV/c, compared to expectations from jet fragmentation. While a number of theoretical interpretations of the data are available, there is not yet a definitive answer to the "baryon puzzle". We investigate the centrality dependence of phi-meson production at mid-rapidity in Au+Au collisions with root s(NN) = 200 GeV. Comparison with the proton and anti-proton spectra reveal similar shapes, as expected for soft production described by hydrodynamics. However, the absolute yields show a different centrality dependence. The nuclear modi. cation factors for phi are similar to those of pions, rather than (anti) protons that have similar mass. At intermediate p(T), baryon/meson effects seem to be more important than the mass effects, in support of recombination models.