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Baryon Resonance Extraction from Pi Nucleon Data using a Multichannel Unitary Model

S. A. Dytman·T. P. Vrana·T. S. H. Lee
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Abstract

We present organization and solutions for a new analysis of all $πN$ elastic and the major inelastic channels to extract detailed characteristics of the contributing baryon resonances. This work is based on the work of R. Cutkosky and collaborators at CMU about 20 years ago. The model features analyticity at the amplitude level and unitarity. Results are similar to previous analyses for strongly excited states, but can vary considerably from previous analyses when the states are weak, the data is poor, or there is a strong model dependence. We emphasize the S_{11}(1535) resonance which has particularly strong model dependence.

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S. A. Dytman, T. P. Vrana, T. S. H. Lee. 1997-02-18. Baryon Resonance Extraction from Pi Nucleon Data using a Multichannel Unitary Model. https://arxiv.org/abs/nucl-th/9702033

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