RANDOM VELOCITY-FIELD CORRECTIONS TO THE F-MODE .3. A PHOTOSPHERIC RANDOM FLOW AND CHROMOSPHERIC MAGNETIC-FIELD

The combined effect of a photospheric random flow and a chromospheric magnetic field on the frequencies of the f-mode is studied for a simple model of the photosphere and chromosphere. The photosphere and chromosphere are approximated as inviscid fluids with constant mass densities rho1 and rho2. The photosphere is taken to be free of a magnetic field and subject to a random flow and the chromosphere is in static equilibrium but permeated by a horizontal magnetic field. Numerical solutions show that the frequencies of the f-mode depart from the parabola omega2=gk(rho1-rho2)/(rho1+rho2)+k2V2(A)rho2/rho1+rho2) at high wavenumbers k.