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arXiv · hep-ph/0501112

Antiproton-Proton Channels in J/psi Decays

B. Loiseau·S. Wycech
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Abstract

The recent measurements by the BES Collaboration of J/psi decays into a photon and a proton-antiproton pair indicate a strong enhancement at the proton-antiproton threshold not observed in the decays into a neutral pion and a proton-antiproton pair. Is this enhancement due to a proton-antiproton quasi-bound state or a baryonium? A natural explanation follows from a traditional model of proton-antiproton interactions based on G-parity transformation. The observed proton-antiproton structure is due to a strong attraction in the 1S0 state, and possibly to a near-threshold quasi-bound state in the 11S0 wave.

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B. Loiseau, S. Wycech. 2005-12-16. Antiproton-Proton Channels in J/psi Decays. https://doi.org/10.1103/physrevc.72.011001

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