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arXiv · 2509.11290

Roper resonance $N^*(1440)$ from charmonium decays

Bing-Song Zou
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Abstract

The Roper resonance $N^*(1440)$ was discovered by David Roper in 1964 through sophisticated partial-wave analyses of $\pi N$ scattering data. However the first direct observation of the Roper resonance peak in the $\pi N$ invariant mass spectrum was only realized 40 years later from the charmonium decay $J/\psi\to\bar pn\pi^+ +c.c.$ at Beijing Electron-Positron Collider. The further observations of the Roper resonance production from various charmonium decays helped to reveal its multiquark nature with large $\sigma N$ component.

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Bing-Song Zou. 2025-09-14. Roper resonance $N^*(1440)$ from charmonium decays. https://arxiv.org/abs/2509.11290

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