Neutrino oscillations in noisy media.

We develop the Reddeld equation for delta-correlated gaussian noise and apply it to the case of two neutrino avor or spin precession in the presence of a noisy matter density or magnetic eld, respectively. The criteria under which physical uctuations can be well approximated by the delta-correlated gaussian noise for the above cases are examined. Current limits on the possible neutrino magnetic moment and solar magnetic eld suggest that a reasonably noisy solar magnetic eld would not appreciably aaect the solar electron neutrino ux. However, if the solar electron density has uctuations of a few percent of the local density and a small enough correlation length, the MSW eeect is suppressed for a range of parameters.