Low Latitude Ionospheric foF2 Variability and F2-Region Virtual Height Response During Low Solar Activity

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Published: Feb 16, 2024
Keywords:
Critical frequency (foF2), Relative Deviation Index (VR), Virtual Height (h’F2), Low Solar Activity (LSA)

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O. E. Ehinlafa
G. A. Àlàgbé
Department of Pure & Applied Physics, Ladoke Akintola University of Technology, Ogbomoso, Nigeria
O. K. Onanuga
Department of Physical Sciences, Lagos State University of Science and Technology, Ikorodu, Nigeria
J. O. Adeniyi
Private Individual, Pipeline Road, Ilorin, Nigeria

Abstract

Diurnal, seasonal and annual critical frequency relative deviation index and virtual height (h′F2) response of F2-region ionosphere was studied during a low solar activity over Ilorin (latitude 8.31°N, longitude 4.34°E, dip latitude 2.95o), a low latitude station along the equatorial anomaly trough. The relative deviation index and mean were used for the analysis of critical frequency (foF2) and virtual height (h′F2) respectively. The least relative deviation index (2-17%) was obtained during the day; it increased at night (8-55%); the highest value obtained during pre-sunrise (17-68%), for the period of low solar activity. Two main peaks were noticed in relative deviation index and virtual height: the pre-sunrise peak, which is higher, and the post-sunset peak. Annually, relative deviation index and virtual height peak at 44% and 275 km respectively, for the pre-sunrise period; and at 37% and 295 km respectively, for the post-sunset period, during the low solar activity. In general, the value of the pre-sunrise peak is higher than that of the post-sunset peak for both relative deviation index and virtual height during the entire season.

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How to Cite
Ehinlafa, O. E., Àlàgbé, G. A., Onanuga, O. K., & Adeniyi, J. O. (2024). Low Latitude Ionospheric foF2 Variability and F2-Region Virtual Height Response During Low Solar Activity. Nigerian Journal of Physics, 32(2), 105–111. Retrieved from https://njp.nipngr.org/index.php/njp/article/view/153
Issue
Vol. 32 No. 2 (2023): Nigerian Journal of Physics - Vol. 32 No. 2
Section
Articles
Author Biographies

G. A. Àlàgbé, Department of Pure & Applied Physics, Ladoke Akintola University of Technology, Ogbomoso, Nigeria

Senior Lectuer, Department of Pure and Applied Physics

O. K. Onanuga, Department of Physical Sciences, Lagos State University of Science and Technology, Ikorodu, Nigeria

Senior Lecturer, Department of Physical Sciences

J. O. Adeniyi, Private Individual, Pipeline Road, Ilorin, Nigeria

Professor of Physics, Private Research Cenre

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