Determination of the ultraviolet emission flux from solar flares on the basis of the disturbances in the ionospheric E-layer

An estimate of the increments in the absolute values of the extreme ultraviolet emission (shorter than 105 nm) from solar flares is obtained. A comparison between the absolute values of the solar ultraviolet emission flux from direct satellite-borne measurements and the results of a calculation of this flux, carried out on the basis of critical frequencies measurements in the daytime midlatitude E layer during flares, is performed. It was shown that the calculated ultraviolet emission fluxes are similar to the fluxes measured from satellites.