Analysis of toponium mass spectra with the T-matrix formalism

Toponium, the bound state of a top quark and its antiquark, is unique among particle interactions. The top quark has a much larger mass than any other quark, so it typically decays much more quickly than it can hadronize. Due to this large width, it behaves differently to other heavy quarkonia. While other heavy quarks are able to form particles much quicker than the rate at which they decay, the top quark has a decay width which is on a similar order to the binding energy of toponium. Because this behavior is unique among heavy quarks, the study of toponium may lead to insight on the nature of the strong interaction. This work attempts to characterize the mass spectrum of toponium. The propagator of a particle is a probabilistic representation of its location over time. The T-matrix formalism, which was used here, is particularly suited for the implementation of the large top quark decay width into its propagator. The amplitude of the scattering interaction between the toponium system, which results in a peak where the bound state is formed, was determined for a range of input energies.