Electromagnetic meson exchange currents and the Sachs nucleon form factors

The operator of the nuclear electromagnetic isovector pi-meson exchange current is constructed starting from the one-nucleon current in the Sachs parametrization and the two-nucleon pi-exchange Born amplitude primarily in pseudoscalar pi N-coupling but mixtures of pseudoscalar-pseudovector coupling have been considered in a nuclear potential, too. The current satisfies the continuity equation up to the considered order O(1/M(3)). In addition, an extension of this model is presented to a current independent of the ps-pv mixing.