Using the Single Quark Transition Model to predict nucleon resonance amplitudes

We present predictions for the $γ^\ast N \to N^\ast$ helicity amplitudes, where $N^\ast$ is a member of the $[70,1^-]$ supermultiplet. We combine the results from the single quark transition model for the helicity amplitudes with the results of the covariant spectator quark model for the $γ^\ast N \to N^\ast(1535)$ and $γ^\ast N \to N^\ast(1520)$ transitions. The theoretical estimations from the covariant spectator quark model are used to calculate three independent functions $A,B$, and $C$ of $Q^2$, where $Q^2=-q^2$ and $q$ is the momentum transfer. With the knowledge of the functions $A,B$, and $C$ we estimate the helicity amplitudes for the transitions $γ^\ast N \to N^\ast(1650)$, $γ^\ast N \to N^\ast(1700)$, $γ^\ast N \to Δ(1620)$, and $γ^\ast N \to Δ(1700)$. The analysis is restricted to reactions with proton targets. The predictions for the transition amplitudes are valid for $Q^2 > 2$ GeV$^2$.

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