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A simple plan for the Delta resonance

N. E. Ligterink
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Abstract

We construct the $Δ$ resonance as a superposition of a bare $Δ$ state and the $πN$ continuum. It is parametrized by three coupling constants for local $πN Δ$ and $ππN N$ couplings and the $Δ$ mass. The latter incorporates the mass renormalization due to the $πN Δ$ interaction, while the results depend only weakly, if at all, on its wave-function renormalization. Three more renormalization constants are needed for the derivative contact interaction. They allow one to generate the $Δ$ resonance dynamically. A large number of fits test the quality of different model assumptions in the $P_{33}$, $P_{31}$ and $P_{13}$ p-wave $πN$ scattering channels.

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N. E. Ligterink. 2002-12-16. A simple plan for the Delta resonance. https://doi.org/10.1142/s0217751x03014344

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