A new solution to the solar neutrino deficit

We reexamine the transition magnetic moment solution to the solar neutrino problem. We argue that the absence of large time variations in the Super-Kamiokande rate provides strong evidence against spin-flavor flip in the solar convective zone. Spin-flavor flip could, however, occur in the primordial magnetic field in the radiative zone. We compute the longest-lived toroidal mode for this field and show that spin-flavor flip in the radiative zone can account for all available solar data.