Short term prediction of E greater than or equal to 10 MeV proton fluxes from solar flares

Both the anisotropic and isotropic diffusion theories can be used to extrapolate proton fluxes for E greater than or equal to 10 meV for over 50% of the particle events. The isotropic diffusion theory uses a diffusion coefficient: D = Mr sup beta. It was found that M and beta tended to be functions of flare position on the solar disk. A measurement of the interplanetary flux in near earth space gives a good indication of the polar cap fluxes. It was found that the 30 MHz absorption over the poles during a PCA is proportional to the square root of the integral proton flux E greater than or equal to 11 meV in interplanetary space, J = KA squared, with K = 8 plus or minus 2 and J in protons/sq cm-sec-ster.