Scaling properties and charge dependence of particle ratio fluctuations at RHIC

It has been suggested that the existence of a QCD phase transition would cause an increase and divergence of fluctuations. Thus event-by-event particle ratio fluctuations could be used to study strangeness and baryon number fluctuations near the critical point in the QCD phase diagram. In this paper, we present dynamical K/??, p/??, and K/p ratio fluctuations from Au+Au collisions at $\sqrt {s_{NN} } $ = 7.7 to 200 GeV. Charge dependent results as well as multiplicity scaling properties of these fluctuation results are discussed. The STAR data are compared to different theoretical model predictions and previous experimental results.