2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/177787We obtain analytic expressions for the third-order corrections due to the strong interaction Coulomb potential to the S-wave Green function, energy levels and wave functions at the origin for arbitrary principal quantum number n. Together with the known non-Coulomb correction this results in the complete spectrum of S-states up to order alpha_s^5. The numerical impact of these corrections on the Upsilon spectrum and the top quark pair production cross section near threshold is estimated.24 pages, LaTeX, v2: eq.(30) corrected (-13/8->-15/8)High Energy Physics - PhenomenologyThird-order Coulomb corrections to the S-wave Green function, energy levels and wave functions at the origintext