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arXiv · 0812.3418

Baryon resonances in the mean field approach and a simple explanation of the Theta+ pentaquark

Dmitri Diakonov
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Abstract

We suggest to classify baryon resonances as single-quark states in a mean field, and/or as its collective excitations. Identifying the Roper resonance N(1440), the nucleon resonance N(1535), and the singlet hyperon Lambda(1405) as single-quark excitations, we find that there must be an exotic S=+1 baryon resonance Theta+ (the "pentaquark") with a mass about 1440+1535-1405=1570 MeV and spin-parity one-half-plus. We argue that Theta+ is an analog of the Gamov--Teller excitation long known in nuclear physics.

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Dmitri Diakonov. 2008-12-17. Baryon resonances in the mean field approach and a simple explanation of the Theta+ pentaquark. https://doi.org/10.1134/s0021364009180015

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