N-$\Delta$ transition form factors

Nucleon and $\Delta$ amplitudes have been obtained by solving a Poincar$\acute{e}$-covariant Faddeev equation, which describes baryons as composites of confined-quarks and confined-nonpointlike-diquarks. The amplitudes were used to calculate the nucleon form factors. The calculation predicts a ratio $\mu_{p}G^{p}_{E}/G^{p}_{M}$ that agrees with extracted JLab data and also predicts that this ratio will pass through zero at $Q^2 = 6.5 \rm{GeV^2}$. This prediction will be tested in forthcoming JLab experiments. We have extended the framework to study the electromagnetic N-$\Delta$ transition form factors. Results for the ratios $G_{E}(p^2)/G_{M}(p^2)$ and $G_{C}(p^2)/G_{M}(p^2)$ are compared with observations. Effects of pion loops, which in dynamical coupled-channel models contribute substantially to $G_{C}(p^2)/G_{M}(p^2)$ at low $Q^2$, are also considered.