Spectra of heavy quarkonia in a Bethe-Salpeter-equation approach
  In a covariant Bethe-Salpeter-equation approach and with a rainbow-ladder truncated model of QCD, we investigate the use of an effective interaction with the goal of reproducing QCD phenomenology. We extend previous studies and present results for ground and excited meson states in the bottomonium and charmonium systems, where the results are surprisingly good for most states. In addition, we formulate a critical outlook on states with exotic quantum numbers as well as the light-quark domain. 
Thomas Hilger, Carina Popovici, Maria Gomez-Rocha, Andreas Krassnigg
hep-ph hep-ex