Radiative corrections to the decays KL0→e+e- and KL0→μ+μ-

We calculate the rates and lepton (l) invariant mass distributions for decays of the form 0-+→l+l-γ, which are important radiative corrections to the purely leptonic decays 0-+→l+l-. Our approach uses the loop diagrams which arise by including the two photon intermediate state and we retain the imaginary parts of the loops a radiative extension of the open-quotes unitarity boundclose quotes for the process. These results are compared with those obtained using a model in which the meson couples directly to the leptons. copyright 1999 The American Physical Society