Plausible effects of equatorial vertical plasma drifts on F2-region sustainable peak electron density in ionospheric environment

Abstract

Abstract F2-region sustainable electron density (N m F2) morphology as well as the effects of vertical E × B plasma drifts (v z ) in ionospheric environment for a location of Ilorin (8.5°N lat., 4.5°E long., dip 2.95o lat.), an equatorial anomaly station during solar minimum (SM) period were investigated. The 10-international quiet days (IQD s ) of electron density and vertical plasma drifts estimated from peak heights, hmF2 data were used and its monthly means computed across each local time period. Diurnally, the daytime occurrences in N m F2 and v z had two characteristic peaks: pre-noon and post-noon peaks for all seasons. The N m F2 and v z pre-noon peak values are (7.3 - 8.5) × 10 11 elm − 3 and (1.0-6.4) ms −1 respectively, and the post-noon peak values in N m F2 and v z are (6.7 - 10.7) × 10 11 elm- 3 and (0.5-2.2) ms −1 respectively for all seasons. Also, only v z exhibited evening pre-reversal enhancement (PRE) and night downward reversal enhancement (DRE) peaks at different local times for all seasons. The evening PRE peak values are [(-0.5)-0.6] ms −1 about 1800 hr and the night DRE peaks values are [(-0.9)-(0.2)] ms −1 about 2100 hr for all seasons. The same sensations ensued in the annual patterns of N m F2 and v z . Generally, the N m F2 and v z values of post-noon peak (10.7 × 10 11 elm −3 and 2.2 ms- 1 ) are greater than the pre-noon peak ( 7.3 × 10 11 elm − 3 and 1.0 ms −1 ) for all seasons; and their values were greatest in Equinox (8.5 × 10 11 elm − 3 and 6.4 ms −1 ) and lowest in Solstice (6.7 × 10 11 elm − 3 and 0.6 ms −1 ). The N m F2 and v z steady and continuous fall for all seasons indicates the electrons rapidly driving away from the equatorial ionosphere that is caused by ionization of sun’s radiation. The noticed concurrent post-sunset rise in drifts of vertical E × B relatively compared with swift descent in N m F2 for all seasons conclude that electrons drifting away from the equator are at a region of low rate due to recombination loss. It is considerately stated that same study under closely related conditions in the ionospheric environment be done for a well claim.