Earth Planets Space, Vol. 57 (No. 9), pp. 871-878, 2005

Low latitude N_e and T_e variations at 600 km during 1 March 1982 storm from HINOTORI satellite

K. I. Oyama¹, D. R. Lakshmi^1,2, I. Kutiev³, and M. A. Abdu⁴

¹Institute of Space and Astronautical Science, 3-1-1, Yoshinodai, Sagamihara, Kanagawa, Japan
²R&T Unit for Navigational Electronics, Osmania University, Hyderabad 500007, India
³Geophysical Institute, Bulgarian Academy of Sciences, Sofia, Bulgaria
⁴Instituto Nacional de Pesquisas Espaciais-NPE C.P. 515-12201-970, Sao Jose dos Campos, SP, Brazil

(Received June 9, 2004; Revised June 16, 2005; Accepted June 21, 2005)

Abstract: This paper presents for the first time a study of HINOTORI satellite measurements of electron density and electron temperature in the topside ionosphere exclusively for magnetic storm departures. Special focus was given to the major storm of 1 March, 1982. While large enhancements in T_e characterize the day time storm response, marked increases in N_e dominate the night time deviations. The night time N_e enhancements which are rather remarkable during 0000-0400 LT are also found to be accompanied by significant T_e increases, by as much as 300 K. The statistical picture that emerges from the study of a large number of storms suggests significant nocturnal T_e enhancements which correlate with the magnitudes of storm intensities. Ring current particles through charge exchange processes seem to be a major source of heat input to thermal electrons, though other sources may also be important.
Key words: Electron temperature, ionospheric storm, low latitude, satellite data, storm time.