On the Dependence of F2 Layer Critical Frequency on F10.7 Solar Flux at an Equatorial Station

ENGLISH/ANGLAIS] Affiliations: 1 Department of Industrial Physics, Landmark University, Omu-Aran, Kwara State, NIGERIA 2 Department of Physics, University of Ilorin, Ilorin, Kwara State, NIGERIA Address for Correspondence/ Adresse pour la Correspondance: stevewolex1@yahoo.com Accepted/Accepté: February, 2012 Citation: Ikubanni SO, Adeniyi JO. On the Dependence of F2 layer critical frequency on F10.7 solar flux at an Equatorial station World Journal of Engineering and Pure and Applied Sciences 2012;2(3):85-91. The dependence of the critical frequency of the F2 layer on solar radio flux of 10.7 cm wavelength (F10.7) was studied using data from a low latitude station of Ouagadougou, Burkina Faso (Lat. 12.4o N, Long. 1.5oW, dip. 5.7). These span a period of 11 years i.e. 1985 1995 (solar cycle 22). Hourly coefficient of correlation between the hourly-monthly averaged values of foF2 and monthly averaged values of F10.7 index was obtained using the Pearson’s correlation formula. These correlations was found to be dependent on time and season (or month) of the year. Good correlation (r > 0.5) was observed for larger part of the day and poor correlation (r < 0.5) was observed for few hours of the nighttime except during December solstice (December and January). Generally, daytime correlation is high (r > 0.7) for all seasons. High correlation (r > 0.7) is observed during December solstice for both daytime and nighttime hours. The possible reason for December solstice observation was discussed.

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