Forward-Peakedνe−eScattering and the Solar-Neutrino Problem

The possibility that multiple ${\nu }_e-e$ scattering within the sun can account for the low solar-neutrino counting rates is considered. In the absence of ${\nu }_e-e$ scattering data, bounds are imposed from ${\overline{\nu }}_e-e$ data, introducing a requirement for strong forward peaking. Generalized four-fermion interactions calculated to first order are found to be inadequate. Electromagnetic ${\nu }_e-e$ interactions with a finite neutrino magnetic moment are found to be satisfactory, but require a seemingly unphysical neutrino form factor corresponding to a mean neutrino radius of ${\overline{r}}_{\nu }>7\mathrm{}\times {10}^{-10\mathrm{}}$ cm.