Two-loop QED radiative corrections to the decay pi0 to e+e-: the virtual corrections and soft-photon bremsstrahlung
2011
Abstract
This paper is devoted to the two-loop QED radiative corrections to the decay of the neutral pion to the electron-positron pair. We compute the virtual corrections without using any approximation and we take into account all the relevant graphs with the inclusion of those omitted in the previous approximative calculations.
The bremsstrahlung is then treated within the soft photon approximation. We compare the exact two-loop results with existing approximative calculations of QED corrections and find significant disagreement in the kinematical region relevant for the KTeV experiment.