Using particle ratios to explore the limits of the thermodynamic model of heavy ion collisions

The thermodynamic model of heavy ion collisions predicts the shape of particle spectra emitted from a source using a number of physical parameters. The chemical potential, which is one of these parameters, can be directly investigated by taking the ratio of spectra for a specific isotope from two different reaction systems. I will be discussing the effects of using the shapes of these ratios instead of integrated yields as well as differentiating between heavy residues and emitted fragments to explore the limits of this model.