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arXiv · hep-ph/9703339

Complete spin structure of the pion-nucleon-loop delta self-energy

C. L. Korpa
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Abstract

The complete spin structure of the pion-nucleon-loop contribution to the delta self-energy and dressed propagator is calculated in vacuum, with the most general form of the pion-nucleon-delta vertex. The imaginary parts of the ten Lorentz-scalar coefficients are calculated in closed form, while the real parts are obtained numerically from a dispersion relation. The effect of the pion-nucleon-delta coupling constants and form-factor on the pion-nucleon phase-shift in the spin-3/2 isospin-3/2 channel is studied.

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C. L. Korpa. 1997-03-17. Complete spin structure of the pion-nucleon-loop delta self-energy. https://doi.org/10.1007/bf03157996

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