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Evidence for the fourth P11 resonance predicted by the constituent quark model

Simon Capstick·T. -S. H. Lee·W. Roberts·A. Svarc
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Abstract

It is pointed out that the third of five low-lying P11 states predicted by a constituent quark model can be identified with the third of four states in a solution from a three-channel analysis by the Zagreb group. This is one of the so-called ``missing'' resonances, predicted at 1880 MeV. The fit of the Zagreb group to the pi N -> eta N data is the crucial element in finding this fourth resonance in the P11 partial wave.

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Simon Capstick, T. -S. H. Lee, W. Roberts, A. Svarc. 1999-04-06. Evidence for the fourth P11 resonance predicted by the constituent quark model. https://doi.org/10.1103/physrevc.59.r3002

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