Interpreting the Neutron's Electric Form Factor: Rest Frame Charge Distribution or Foldy Term?

Abstract

The neutron's electric form factor contains vital information on nucleon structure, but its interpretation within many models has been obscured by relativistic effects. I demonstrate that, to leading order in the relativistic expansion of a constituent quark model, the Foldy term cancels exactly against a contribution to the Dirac form factor $F_1$ to leave intact the naive interpretation of $G_E^n$ as arising from the neutron's rest frame charge distribution.