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Spectral-fluctuations test of the quark-model baryon spectrum

C. Fernandez-Ramirez·A. Relano
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Abstract

We study the low-lying baryon spectrum (up to 2.2 GeV) provided by experiments and different quark models using statistical tools which allow to postulate the existence of missing levels in spectra. We confirm that the experimental spectrum is compatible with Random Matrix Theory --the paradigmatic model of quantum chaos--, and we find that the quark models are more similar to a Poisson distribution, which is not compatible with what should be expected in a correlated spectrum. From our analysis it stems that the spectral fluctuation properties of quark-model spectra are incompatible with experimental data. This result can be used to enlighten the problem of missing resonances.

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C. Fernandez-Ramirez, A. Relano. 2007-01-15. Spectral-fluctuations test of the quark-model baryon spectrum. https://doi.org/10.1103/physrevlett.98.062001

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