LORENTZ STRUCTURE OF THE CORNELL POTENTIAL

Quasi-relativistic variational calculations supplemented by the virial theorem are used to improve the determination of the Lorentz structur e of the quark-antiquark potential in quarkonium. No satisfactory solu tion exists for a purely vectorlike internal 1/r and a purely scalar e xternal r interactions. We present the result of assuming an admixture of scalar, pseudoscalar and vector Lorentz effective potentials. Solu tions with and without a pseudoscalar potential are found for charmoni um and bottomonium, within a 1 MeV precision. The toponium spectra for m(t) = 150 GeV top quark are reported.