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arXiv · 1111.6150

Evidence for a spin-quartet of nucleon resonances at 2\,GeV

A. V. Anisovich·E. Klempt·V. A. Nikonov·A. V. Sarantsev·U. Thoma
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Abstract

Results from a multi-channel partial wave analysis of elastic and inelastic $πN$ and $γN$ induced reactions are presented. The analysis evidences the existence of a spin-quartet of nucleon resonances with total angular momenta $J^P=1/2^+,..., 7/2^+$. All states fall into a $\pm130$\,MeV mass gap centered at 1.97\,GeV. The spin quartet is at variance with S-wave diquark configurations required in classical di-quark models.

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A. V. Anisovich, E. Klempt, V. A. Nikonov, A. V. Sarantsev, U. Thoma. 2011-12-21. Evidence for a spin-quartet of nucleon resonances at 2\,GeV. https://doi.org/10.1016/j.physletb.2012.03.066

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