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Including the $Δ(1232)$ resonance in baryon chiral perturbation theory

C. Hacker·N. Wies·J. Gegelia·S. Scherer
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Abstract

Baryon chiral perturbation theory with explicit $Δ(1232)$ degrees of freedom is considered. Using the extended on-mass-shell renormalization scheme, a manifestly Lorentz-invariant effective field theory with a systematic power counting is obtained. As applications we discuss the mass of the nucleon, the pion-nucleon sigma term, and the pole of the $Δ$ propagator.

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C. Hacker, N. Wies, J. Gegelia, S. Scherer. 2005-05-06. Including the $Δ(1232)$ resonance in baryon chiral perturbation theory. https://doi.org/10.1103/physrevc.72.055203

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