Vector positronium states in three-dimensional QED

The homogeneous Bethe-Salpeter equation is solved in the quenched ladder approximation for the vector positronium states of four-component quantum electrodynamics in two space and one time dimensions. Fermion propagator input is from a rainbow approximation Dyson-Schwinger solution, with a broad range of fermion masses considered. This work is an extension of earlier work on the scalar spectrum of the same model. The nonrelativistic limit is also considered via the large fermion mass limit. Classification of states via their transformation properties under discrete parity transformations allows analogies to be drawn with the meson spectrum of QCD. copyright 1997 The American Physical Society