Positronium energy levels at order mα7: Vacuum polarization corrections in the two-photon-annihilation channel

Abstract

We have calculated all contributions to the energy levels of parapositronium at order mα7 coming from vacuum polarization corrections to processes involving virtual annihilation to two photons. This work is motivated by ongoing efforts to improve the experimental determination of the positronium ground-state hyperfine splitting.

Keywords

• Quantum electrodynamics (QED)
• Positronium
• Hyperfine splitting (hfs)