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arXiv · 2602.15320

The Roper Resonance: Still Controversial 60 Years Later

Anthony W Thomas
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Abstract

Few baryon resonances have generated as much discussion, even controversy, as the first positive parity excited state with nucleon quantum numbers. We re-examine the issue using insight gained from lattice QCD, complemented by Hamiltonian effective field theory. In doing so, we also examine the distinction between a state that can be naturally described as a quark model state and one that is dynamically generated.

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Anthony W Thomas. 2026-02-17. The Roper Resonance: Still Controversial 60 Years Later. https://doi.org/10.5506/aphyspolb.57.2-a6

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