This is event is characterized by a low solar wind speed of 275 km/s, a small positive and only slight sign changes in the component of the IMF during the period. IMP8 is located in the tail region. The index at the time of the event was below 1.0.
A large area of backscatter has been recorded during this event from both radars. Visible in Figure 5.64 are three distinct regions of double-peak spectra occurrences. One patch is centered at about E and N, an extended band stretches from E and N in a curve southeast to E and N and a patch is located further south, centered at about E and N.
Figure 5.64: Map of spectral findings from the Saskatoon and Kapuskasing radars:
25 Feb/95
As can be seen in Figure 5.65, the track of the satellite is situated very well for observations. It enters the south-east patch of double-peaked spectra at about , exits at about and reenters the extended band at , leaving at .
Figure 5.65: Peak-map with overlaid flight path of the DMSP F12 satellite: 25
Feb/95
Figure 5.66: Average electron energy and flux determined from SSJ/4 instrument
measurements: 25 Feb/95
It is apparent from Figure 5.66 that both periods include satellite observations of increased flux. The low energy precipitation begins at about with a sharp peak. The features are more apparent in Figure 5.67 where it can be seen that F-layer ionization is high from about to and again from to . Both periods correspond to regions of double-peaked spectra seen with the radar.
Figure 5.67: Estimated ionization rates at E- and F-layer heights determined from electron
spectra measurements: 25 Feb/95
The conductance graphs of Figure 5.68 show little E-layer conductance changes.
Figure 5.68: Estimated E-layer conductivities from the Robinson model: 25 Feb/95
The velocity map of Figure 5.69 is characterized by low velocities and complex convection patterns. The regions of double-peaked spectra are present in all areas of the flow map and do not seem to correspond to a particular region.
Figure 5.69: SuperDARN velocity map: 25 Feb/95