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Form Factors of Baryons in a Confining and Covariant Diquark-Quark Model

M. Oettel·S. Ahlig·R. Alkofer·C. Fischer
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Abstract

We treat baryons as bound states of scalar or axialvector diquarks and a constituent quark which interact through quark exchange. This description results as an approximation to the relativistic Faddeev equation for three quarks which yields an effective Bethe-Salpeter equation. Octet and decuplet masses and fully four-dimensional wave functions have been computed for two cases: assuming an essentially pointlike diquark on the one hand, and a diquark with internal structure on the other hand. Whereas the differences in the mass spectrum are fairly small, the nucleon electromagnetic form factors are greatly improved assuming a diquark with structure. First calculations to the pion-nucleon form factor also suggest improvements.

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M. Oettel, S. Ahlig, R. Alkofer, C. Fischer. 1999-11-01. Form Factors of Baryons in a Confining and Covariant Diquark-Quark Model. https://doi.org/10.1063/1.1303012

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