Narrow e+e- peaks in heavy-ion collisions and a possible new phase of QED.

Abstract

Motivated by the otherwise inexplicable ${e}^{+}{e}^{\ensuremath{-}}$ peaks observed in heavy-ion collisions at GSI, we postulate the existence of a new phase of QED. The transition to this new phase is induced by the presence of unusual background electromagnetic field environments. Strong-coupling calculations of the spectrum of confined QED are reported, and the masses fit well with the observed peaks.