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Can the observed enhancement in the mass spectrum of p \bar p in J/ψ\to γp \bar p be interpreted by a possible p \bar p bound state

Xiang Liu·Xiao-Qiang Zeng·Yi-Bing Ding·Xue-Qian Li·Hong Shen·Peng-Nian Shen
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Abstract

Provided the enhancement in the $p \bar{p}$ spectrum in radiative decay $J/ψ\to γp \bar{p}$ observed by the BES collaboration is due to an existence of a $p \bar{p}$ molecular state, we calculate its binding energy and lifetime in the linear $σ$ model. We consider a possibility that the enhancement is due to a $p \bar p$ resonance which is in either S-wave or P-wave structure and compare our results with the data.

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Xiang Liu, Xiao-Qiang Zeng, Yi-Bing Ding, Xue-Qian Li, Hong Shen, Peng-Nian Shen. 2004-06-10. Can the observed enhancement in the mass spectrum of p \bar p in J/ψ\to γp \bar p be interpreted by a possible p \bar p bound state. https://arxiv.org/abs/hep-ph/0406118

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