Search for the Flavor-Changing Neutral-Current Decays $D^{+}\to {\pi }^{+}{\mu }^{+}{\mu }^{-}$ and $D^{+}\to {\pi }^{+}{e}^{+}{e}^{-}$

Fermilab E791 Collaboration

We report the results of a search for the flavor-changing neutral-current decays $D^{+}\to {\pi }^{+}{\mu }^{+}{\mu }^{-}$ and $D^{+}\to {\pi }^{+}{e}^{+}{e}^{-}$ in data from Fermilab charm hadroprod…