Scattering of Electrons with an Intrinsic Electric Dipole Moment

Abstract

The elastic scattering of electrons with a small intrinsic electric dipole moment (e.d.m.) by spinless targets is discussed in the first and second Born approximations. For large momentum transfer ($q\ensuremath{\sim}500$ Mev/c) the e.d.m. contribution to the elastic scattering cross section becomes important even for values $\ensuremath{\lambda}\ensuremath{\sim}{10}^{\ensuremath{-}3}$ (where $\ensuremath{\lambda}$ is the e.d.m. in units of $e$ times the Compton wavelength of the electron). Thus, it seems likely that experiments involving high-energy electrons may give valuable information on the hypothetical existence and upper limit of the e.d.m. interaction. It is also found, in the first Born approximation, that at sufficiently high energies the existence of the e.d.m. can change the polarization of the electron beam from longitudinal to transverse. Finally, asymmetry effects which appear in the second Born approximation are discussed in detail. Detection of these asymmetries or of the spin correlation effects of the first Born approximation mentioned above would imply the noninvariance of the electromagnetic interactions under parity and time reversal.