Comparison of The Very Low Frequency Signal Amplitude in The ISIO and The French Station for The Same Solar Events


Abstract:There are heterogeneity and increase in the percentage of ionization with solar explosions, wherethe so-called sudden ion disturbance (SID), Which can be measured by the so-called very low frequencies(VLF), where used in this study to calculate the extent change of the signals amplitude between the receiverbuilt in our station (ISIO) and the transmitters from different regions of the world comparing that withanother receiver 4000 kilometers north, when location at southern France (A11٣), which receives thesignals from the same transmitters, which we received the same signals and the timing of each solar event.Five events received by our station from the period (2017-6-3) to the period (2017-9-10).These events are compared with a set of events that recorded at different periods .The results showed thatthe signals amplitude in all events is much higher than the signal amplitude received from the Frenchstation. This variation in amplitude is due to the heterogeneity of the receiving location at our station, whichalso means that the ionosphere at the top of this region, which is considered to be part of the subtropicalregions, is different from those near the polar gap.