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arXiv · 1101.1722

Plausible explanation of the $Δ_{5/2^{+}}(2000)$ puzzle

Ju-Jun Xie·A. Martínez Torres·E. Oset·P. González
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Abstract

From a Faddeev calculation for the $π-(Δρ)_{N_{5/2^{-}}(1675)}$ system we show the plausible existence of three dynamically generated $I(J^{P})=3/2 (5/2^{+})$ baryon states below 2.3 GeV whereas only two resonances, $Δ_{5/2^{+}}(1905)(\ast\ast\ast\ast)$ and $Δ_{5/2^{+}}(2000)(\ast\ast),$ are cataloged in the Particle Data Book Review. Our results give theoretical support to data analyses extracting two distinctive resonances, $Δ_{5/2^{+}}(\sim1740)$ and $Δ_{5/2^{+}}(\sim2200),$ from which the mass of $Δ_{5/2^{+}}(2000)(\ast\ast)$ is estimated. We propose that these two resonances should be cataloged instead of $Δ_{5/2^{+}}(2000).$ This proposal gets further support from the possible assignment of the other baryon states found in the approach in the $I=1/2,3/2$ with $J^{P}=1/2^{+},3/2^{+},5/2^+$ sectors to known baryonic resonances. In particular, $Δ_{1/2^{+}}(1750)(\ast)$ is naturally interpreted as a $πN_{1/2^{-}}(1650)$ bound state.

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Ju-Jun Xie, A. Martínez Torres, E. Oset, P. González. 2011-05-25. Plausible explanation of the $Δ_{5/2^{+}}(2000)$ puzzle. https://doi.org/10.1103/physrevc.83.055204

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