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arXiv · 0904.2163

On the structure of the X(1835) baryonium

J. -P. Dedonder·B. Loiseau·B. El-Bennich·S. Wycech
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Abstract

The measurement by the BES collaboration of J/psi -> gamma p pbar decays indicates an enhancement at the p-pbar threshold. In another experiment BES finds a peak in the invariant mass of pi-mesons produced in the possibly related decay J/psi -> gamma pi+ pi- eta'. Using a semi-phenomenological potential model which describes all the N-Nbar scattering data, we show that the explanation of both effects may be given by a broad quasi-bound state in the spin and isospin singlet S wave. The structure of the observed peak is due to an interference of this quasi-bound state with a background amplitude and depends on the annihilation mechanism.

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J. -P. Dedonder, B. Loiseau, B. El-Bennich, S. Wycech. 2009-11-19. On the structure of the X(1835) baryonium. https://doi.org/10.1103/physrevc.80.045207

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