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arXiv · 2010.03052

The Positive-Parity Baryon Spectrum and the Role of Hybrid Baryons

Tanjib Khan·David Richards·Frank Winter
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Abstract

We calculate the low-lying spectra for the positive-parity $\Delta$ and $N$ at two pion masses of 358 and 278 MeV using an isotropic clover action with two degenerate light-quaark and one strange-quark flavors through the application of the generalized variational method within the distillation framework. The spectrum exhibits the general features observed in previous calculations using an anisotropic clover lattice, with a counting of states at least as rich as the quark model. Furthermore, we identify states that are hybrid in nature, where gluonic degrees of freedom play a structural role, indicatinng that such states appear a feature of the excited baryon spectrum, irrespective of the lattice action, or the precise details of the smearing of the lattice interpolating operators used to identify such states.

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BibTeXRIS

Tanjib Khan, David Richards, Frank Winter. 2020-10-06. The Positive-Parity Baryon Spectrum and the Role of Hybrid Baryons. https://doi.org/10.1103/physrevd.104.034503

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