Radar Measurements on Plasmasphere-Ionosphere Coupling
Location
Yosemite National Park
Start Date
2-6-1974 10:30 AM
End Date
2-6-1974 11:00 AM
Description
Ground-based incoherent scatter radar studies of the upper part of the F2 layer are capable of providing considerable information on the coupling between the ionosphere and the plasmasphere by means of cool particles. Observations of the shape of the spectrum of the ion-acoustic component of the echoes may be used to determine the ratio of O+ to H+ ions in the upper F2 region, region and the time variation of the transition altitude used to infer vertical fluxes of ionization into or from the plasmasphere. By measuring the overall Doppler shift of the ion-acoustic echoes, the vertical velocity of the plasma may be determined. After allowing for the velocity established by the growth or decay of the layer, these measurements yield fluxes of ionization into or from the plasmasphere. A third type of study involves observations of the electronic component of the echoes, which are obtained from plasma oscillations stimulated by the presence of fast photelectrons. Since photoelectrons of different energy are responsible for exciting the plasma oscillations observed at different altitudes, it is possible to infer the energy spectrum of the escaping and arriving photoelectron fluxes. Finally, the measurement of electron (and ion) temperature, as a function of altitude, may be used to infer the heat input to the ionosphere from the plasmasphere.
Radar Measurements on Plasmasphere-Ionosphere Coupling
Yosemite National Park
Ground-based incoherent scatter radar studies of the upper part of the F2 layer are capable of providing considerable information on the coupling between the ionosphere and the plasmasphere by means of cool particles. Observations of the shape of the spectrum of the ion-acoustic component of the echoes may be used to determine the ratio of O+ to H+ ions in the upper F2 region, region and the time variation of the transition altitude used to infer vertical fluxes of ionization into or from the plasmasphere. By measuring the overall Doppler shift of the ion-acoustic echoes, the vertical velocity of the plasma may be determined. After allowing for the velocity established by the growth or decay of the layer, these measurements yield fluxes of ionization into or from the plasmasphere. A third type of study involves observations of the electronic component of the echoes, which are obtained from plasma oscillations stimulated by the presence of fast photelectrons. Since photoelectrons of different energy are responsible for exciting the plasma oscillations observed at different altitudes, it is possible to infer the energy spectrum of the escaping and arriving photoelectron fluxes. Finally, the measurement of electron (and ion) temperature, as a function of altitude, may be used to infer the heat input to the ionosphere from the plasmasphere.