Leptonic decay rates of charmonium [Formula presented] and [Formula presented] states

We calculate the leptonic decay rates of the [Formula presented] and the [Formula presented] states of charmonium including their relativistic and single gluonic radiative corrections within the framework of a nonsingular potential model proposed by Gupta, Johnson, Repko, and Suchyta. We find that the relativistic corrections and the single gluonic radiative corrections are both significant. But single gluonic radiative corrections are significantly smaller than the well-known static limit results. Since we work in a formalism where the quarks are assumed to be on mass shell, there is some ambiguity about treating the infrared divergent part of the radiative correction terms.