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arXiv · hep-ph/9606277

Pion-Nucleon Phase Shifts in Heavy Baryon Chiral Perturbation Theory

Alakabha Datta·Sandip Pakvasa
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Abstract

We calculate the phase shifts in the pion-nucleon scattering using the heavy baryon formalism. We consider phase shifts for the pion energy range of 140 to $200 $ MeV. We employ two different methods for calculating the phase shifts - the first using the full third order calculation of the pion-nucleon scattering amplitude and the second by including the resonances $Δ$ and $N^*$ as explicit degrees of freedom in the Lagrangian. We compare the results of the two methods with phase shifts extracted from fits to the pion-nucleon scattering data. We find good to fair agreement between the calculations and the phase shifts from scattering data.

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Alakabha Datta, Sandip Pakvasa. 1997-08-05. Pion-Nucleon Phase Shifts in Heavy Baryon Chiral Perturbation Theory. https://doi.org/10.1103/physrevd.56.4322

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