Magnetospheric (90 – 4000 km) field aligned electron and ion (H+, He+, O+) densities as a function of geomagnetic storm activity

Abstract

Field aligned electron (Ne) and ion densities and their variations as a function of geomagnetic storm activity are important parameters in the physics of the thermosphere, ionosphere, and magnetosphere. Whistler mode (WM) radio sounding [Sonwalkar et al., JGR, 2011] from the IMAGE satellite during 24 Aug – 18 Sep 2005, covering 3 major, 3 moderate, and one minor storm, has permitted measurements of electron and ion densities (90–4000 km) as a function of geomagnetic storm activity. During this period, WM echoes were observed on dayside (MLT∼14, 1.7<L<3.5) and nightside (MLT∼3, 1.8<L<4.5). Here we present results from the analysis of WM echoes observed on dayside between 1.8<L<2.2. The analysis of echoes at other L-shell and nighttime is ongoing. From the analysis of WM echoes observed during quiet times nominal density models were built for Ne and relative ion concentrations (αH+, αHe+, αO+).