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Chiral doublet model for the positive and negative parity nucleons

D. Jido
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Abstract

We discuss the properties of the nucleon (N) and its excited state with odd parity (N*) under the aspect of chiral symmetry, identifying them with suitable representations of the chiral group. It is shown that there are two distinctive schemes to assign the chiral multiplet to N and N*. We construct linear sigma models for N and N* with the two assignments to show their physical implications. We also discuss the in-medium properties of N(1535), comparing the present model with the other chiral model based on the different picture of N*.

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D. Jido. 2003-12-01. Chiral doublet model for the positive and negative parity nucleons. https://arxiv.org/abs/nucl-th/0312005

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