$(Zα)^{4}$ order of the polarization operator in Coulomb field at low energy

2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/201685We derive the low-energy expansion of $(Zα) ^{2}$ and $(Zα) ^{4}$ terms of the polarization operator in the Coulomb field. Physical applications such as the low-energy Delbrück scattering and "magnetic loop" contribution to the $g$ factor of the bound electron are considered.16 pages, 10 figuresHigh Energy Physics - Phenomenology$(Zα)^{4}$ order of the polarization operator in Coulomb field at low energytext