Improvements in the analysis of radiative decay channels in the PEN experiment

The PEN collaboration, an international collaboration led by the University of Virginia, has sought to measure Γ(π→eν(γ))/Γ(π→μν(γ)) to relative precision of 5 × 10^-4 or better.  This measurement provides a key confirmation of the V-A nature of the electroweak interaction and serves as a sensitive probe to physics beyond the Standard Model, manifested in lepton non-universality.  Radiative decays, π→eνγ  and μ→eννγ  are integral parts of the signal for the decay of interest π_e2  and the normalizing μ→eνν decay.   We report on advances in controlling the systematics associated with these radiative decay channels, as well as in controlling backgrounds that mask or mimic the radiative decay channels, e.g., split electromagnetic shower photons.