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arXiv · 1207.4392

The shape of the $Δ$ baryon in a covariant spectator quark model

G. Ramalho·M. T. Pena·A. Stadler
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Abstract

Using a covariant spectator quark model that describes the recent lattice QCD data for the $Δ$ electromagnetic form factors and all available experimental data on $γN \to Δ$ transitions, we analyze the charge and magnetic dipole distributions of the $Δ$ baryon and discuss its shape. We conclude that the quadrupole moment of the $Δ$ is a good indicator of the deformation and that the $Δ^+$ charge distribution has an oblate shape. We also calculate transverse moments and find that they do not lead to unambiguous conclusions about the underlying shape.

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G. Ramalho, M. T. Pena, A. Stadler. 2012-11-09. The shape of the $Δ$ baryon in a covariant spectator quark model. https://doi.org/10.1103/physrevd.86.093022

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