A New State of Baryonium

The recent discovery of a narrow resonance in the decay $J/\psi \to \gamma p \bar{p}$ is described as a zero baryon number, ``deuteron-like singlet ${}^1{S}_0$’’ state. The difference in binding energy of the deuteron (-2.225 MeV) and of the new state (-17.5 MeV) can be accounted for in a simple potential model with a $\lambda \cdot \lambda$ confining interaction.