Relativistic Effects in the Form Factors ofHe3andH3

Relativistic corrections to Schiff's nonrelativistic analysis of the three-body nuclei form factors are estimated. High-energy electron scattering from these nuclei is re-examined using an impulse approximation in which the intermediate nucleon states are taken to propagate and interact as free particles. We conclude that the corrections to the form factors are small (≲5%) for $-q^2\lesssim 8 F^{-2\mathrm{}}$. However, it is shown that they assume great importance if the experiments are used to investigate the neutron charge form factor. Various effects arising from the use of the impulse approximation are discussed. These include considerations of current conservation, of the static limit ($q^2\to 0$), and of the extraction of nuclear form factors from the impulse-approximation nuclear current.