Fluctuations of Particle Ratios and the Abundance of Hadronic Resonances

Abstract

We argue that the event-by-event fluctuations of the ratio of positively charged over negatively charged pions provides a measurement of the number of rho and omega mesons right after hadronization. This finding can be utilized to put the hypothesis of chemical equilibration in relativistic heavy ion collisions to a test. The fluctuation may also serve as an indicator for new physics to be discovered in relativistic heavy-ion collisions.