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Excitation Spectrum in the Friedberg-Lee Model

H. Kowata·M. Arima
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Abstract

The excitation spectrum of the nucleon with the spin 1/2 is examined by using the Friedberg-Lee model containing the constituent quark and the scalar meson. An appropriate way of quantization for the non-linear meson field is employed by taking account of the non-topological soliton existed in the classical level. Our model space for the nucleon resonances includes the three-quark plus one-meson state in addition to the pure three-quark state. The excitation spectrum in this model space shows that the positive parity state appears as the first excited state associated with the 0s-excitation of the scalar meson. The meson excitation also generates the additional negative parity state apart from the well-known 0p-excitation of the quark.

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H. Kowata, M. Arima. 2001-01-09. Excitation Spectrum in the Friedberg-Lee Model. https://doi.org/10.1143/ptp.105.449

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