32-34Results of a statistical analysis of A1 absorption and solar X-ray and Lyman-ɑ fluxes are presented. The observed small positive correlation coefficients between absorption and solar X-ray flux in the 1-8 Ǻ and 8-20 Ǻ bands show that the influence of solar X-rays on absorption is less during low sunspot activity period. Significant positive correlation between Lyman-ex flux and absorption is obtained. Significant positive correlation between D region absorption (separated from total absorption) and Lyman-ɑ flux shows that the influence of Lyman-ɑ radiation on the D region is more than that of X-rays
