Probing Hadronic Structure with The Decay $\Delta \to N{l}^{+}{l}^{-}$

Abstract

We compute the branching ratio for $\Delta \to N{e}^{+}{e}^{-}$ and $\Delta \to N{\mu }^{+}{\mu }^{-}$ in chiral perturbation theory and find that both decays should be observable at CEBAF. With sufficiently low thresholds on the $e^{+}{e}^{-}$ invariant mass a branching ratio of $\sim 10^{-5}$ may be observed for $\Delta \to N{e}^{+}{e}^{-}$. For the $\Delta \to N{\mu }^{+}{\mu }^{-}$ decay mode we predict a branching ratio of $3\times 10^{-7}$. The dependence of the M1 and E2 amplitudes on the momentum transfer will provide a useful test of chiral perturbation theory which predicts $\sim 20\%$ variation over the allowed kinematic range.

Comments: 6 pages, 3 figures, UCSD/PTH 93-06, QUSTH-93-02, Duke-TH-93-48