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arXiv · hep-ph/9711484

The $Δ(1232)$ as an Effective Degree of Freedom in Chiral Perturbation Theory

Joachim Kambor
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Abstract

Heavy baryon chiral perturbation theory including spin 3/2 delta resonances as effective degrees of freedom is reviewed. The theory admits a systematic expansion in the small scale $ε$, where $ε$ collectively denotes soft momenta, the pion mass or the delta-nucleon mass difference. Renormalization is discussed in some detail on the example of the scalar sector of one-nucleon processes, and a reformulation of the principle of resonance saturation for counterterms of the HBChPT lagrangian is sketched. As an application, the polarizabilities of the nucleon are discussed at order $ε^3$.

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Joachim Kambor. 1997-11-26. The $Δ(1232)$ as an Effective Degree of Freedom in Chiral Perturbation Theory. https://doi.org/10.1007/bfb0104904

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