[01] Ayokunnu Olalekan David, Physics Department, The Polytechnic, Ibadan, Nigeria. [02] Ogunsola Oluseyi Enitan, Physics Department, University of Ibadan, Ibadan, Nigeria. [03] Dare Oluseye David, Physics Department, Dominion University Ibadan, Ibadan, Nigeria.

The electron density of the equatorial F1 layer (±30°) of the low latitude region is modeled in this work. The digisonde data used is of the year 2016, a year of low solar activity with sunspot number, Rz (20) of 30. The data used is from seven (7) stations North and South of the region of the low latitude. The stations used are: Guam (13.4°N, 144.5°S dip 12.8°), America; Sanya (18.3°N, 109.5°S dip 25.0°) China; Boa Vista (16.1°N, 22.8°S dip 22.1°) Cape Verde; Campo Grande (20.5°S, 54.6°W dip 22.3°); Cachoeira (12.6°S, 39°W dip -28.0°); Fortaleza (3°S, 38.6°W dip -15.8°) all in Brazil and Jicamarca (12.0°S, 76.9°W dip -0.5°) Peru. The F1 layer was observed in each of the stations used and found to be present between 0700-1800 local time. The percentage occurrence of the layer at 0700 and 1800 local time is 1 and 3% respectively, while that of 0900-1700 local time exceeds 85%. The solar dependency of the layer is characterized and latitudinal variability of the layer is also observed. The index was observed to be in the region of during the Equinox months and during the Solstice months. The prediction from this new model was found to be of order for the minimum error and for the maximum error and found quite close to the observed value at the various stations in the low latitude region.

Electron Density, Equatorial Ionosphere, Low Latitude and Low Solar Activity

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