The five narrow states of masses 1–2 MeV/$c^2$ recently observed in low-energy heavy-ion collisions are interpreted as the ${}_{}{}^1{}_{}{}^{}\mathrm{S}_0^{}{}_{}{}^{}$ and the four P states of an $e^{+}$$e^{\mathrm{-}}$ pair trapped in bags of abnormal QED vacuum. Masses and properties of trapped states of two, three, and many electrons in the bag are discussed. Possible electronless states and electronic states with photons add to the rich spectroscopy of abnormal QED, reminiscent of hadron spectroscopy.

• Received 25 November 1987

DOI:https://doi.org/10.1103/PhysRevD.37.3206