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Effective theory of the Delta(1232) in Compton scattering off the nucleon

Vladimir Pascalutsa·Daniel R. Phillips
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Abstract

We formulate a new power-counting scheme for a chiral effective field theory of nucleons, pions, and Deltas. This extends chiral perturbation theory into the Delta-resonance region. We calculate nucleon Compton scattering up to next-to-leading order in this theory. The resultant description of existing $γ$p cross section data is very good for photon energies up to about 300 MeV. We also find reasonable numbers for the spin-independent polarizabilities $α_p$ and $β_p$.

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Vladimir Pascalutsa, Daniel R. Phillips. 2003-03-15. Effective theory of the Delta(1232) in Compton scattering off the nucleon. https://doi.org/10.1103/physrevc.67.055202

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