On a Neutrino Electroweak Radius

Abstract

We study a combination of amplitudes for neutrino scattering that can isolate a (gauge-invariant) difference of chirality-preserving neutrino electroweak radii for ${\nu }_{\mu }$ and ${\nu }_{\tau }$. This involves both photon and $Z_{\mu }$ exchange contributions. It is shown that the construction singles out the contributions of the hypercharge gauge field $B_{\mu }$ in the standard model. We comment on how gauge-dependent terms from the charge radii cancel with other terms in the relative electroweak radii defined.

16 pages, revtex with embedded figures