Charmonium from Classical Pure SU(3) Yang-Mills Configurations
  A generalized Faddeev-Niemi ansatz for the gluon field is discussed. In its simplest parametrization, the ansatz allows a solution of the classical SU(3) Yang-Mills equations. From these solutions a confining potential for heavy quarkonia is defined. The investigation of charmonium spectra proves that the potential is able to reproduce the experimental spectra at the level of 3%. Moreover, charmonium leptonic and strong decays are investigated. The results are in fair agreement with experimental figures and are in line with other quark model calculations. 
O. Oliveira, R. A. Coimbra