Altitude distribution of electron concentration in ionospheric D-region in presence of time-varying solar radiation flux

摘要

In this paper, we study the influence of solar flares on electronconcentration in the terrestrial ionospheric D-region by analyzing theamplitude and phase time variations of very low frequency (VLF) radio wavesemitted by DHO transmitter (Germany) and recorded by the AWESOME receiver inBelgrade (Serbia) in real time. The rise of photo-ionization rate in theionospheric D-region is a typical consequence of solar flare activity asrecorded by GOES-15 satellite for the event on March 24, 2011 between 12:01 UTand 12:11 UT. At altitudes around 70 km, the photo-ionization and recombinationare the dominant electron gain and electron loss processes, respectively. Weanalyze the relative contribution of each of these two processes in theresulting electron concentration variation in perturbed ionosphere.