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Nucleon and Delta in a covariant quark-diquark model

Volker Keiner
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Abstract

We develop a formally covariant quark-diquark model of the nucleon. The nucleon is treated as a bound state of a constituent quark and a diquark interacting via a quark exchange. We include both scalar and axial-vector diquarks. The underlying Bethe-Salpeter equation is transformed into a pair of coupled Salpeter equations. The space- and timelike electromagnetic form factors of the nucleon are calculated in the Mandelstam formalism for squared momentum transfers up to 3 (GeV/c)^2 above threshold. The model is applied also to the Delta(3/2).

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Volker Keiner. 1996-12-09. Nucleon and Delta in a covariant quark-diquark model. https://arxiv.org/abs/nucl-th/9612018

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