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Electromagnetic N-$Δ$ transition form factors in a covariant quark-diquark model

Volker Keiner
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Abstract

The electromagnetic N-$Δ$ transition form factors are calculated in the framework of a formally covariant constituent diquark model. As a spin-3/2 particle the $Δ$ is assumed to be a bound state of a quark and an axial-vector diquark. The wave function is obtained from a diquark-quark Salpeter equation with an instantaneous quark exchange potential. The three transition form factors are calculated for momentum transfers squared from the pseudothreshold $(M_Δ-M_N)^2$ up to $-2 (GeV/c)^2$. The magnetic form factor is in qualitative agreement with experiment. We find very interesting results for the ratios E2/M1 and C2/M1.

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Volker Keiner. 1996-10-10. Electromagnetic N-$Δ$ transition form factors in a covariant quark-diquark model. https://doi.org/10.1007/s002180050371

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