Leading-order nuclear π-γ exchange force

Abstract
The leading-order isospin-violating force from simultaneous π and γ exchange is calculated. The charge-symmetric, but charge-dependent, force is calculated for static nucleons and in Coulomb gauge. Infrared divergences and other technical problems are discussed. The resulting force is roughly 3 orders of magnitude smaller than OPEP and roughly the same size as the Breit correction to single-photon exchange. The present calculation corresponds to a subset of one-loop diagrams in chiral perturbation theory for isospin violation in the nucleon-nucleon force. © 1996 The American Physical Society.