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26 Jan/95, 16:27 - 16:29 UT

WIND measured a slight increase of the solar plasma speed from 310 to 320 km/s along with a change of tex2html_wrap_inline4540 and tex2html_wrap_inline5474 from zero to a small positive value around the time the event was recorded. IMF conditions were undisturbed otherwise. IMP8 IMF measurements compare well with the WIND measurements. The tex2html_wrap_inline4548 index at the time of the event was 1.0.

Figure 5.34 shows that backscatter was observed by both radars from an extended region. The Kapuskasing radar, however, shows an echo gap from tex2html_wrap_inline5318 E to tex2html_wrap_inline5320 E, centered at a latitude around tex2html_wrap_inline5324 N. A patch of double-peaked spectra was observed mostly by the Kapuskasing radar from tex2html_wrap_inline5512 E to tex2html_wrap_inline5370 E at a latitude around tex2html_wrap_inline5326 N.

Figure 5.34: Map of spectral findings from the Saskatoon and Kapuskasing radars: 26 Jan/95

In Figure 5.35 the satellite track for this event is shown; one can identify two regions. First, coming from the north, the satellite passes by the double-peaked spectra region at about tex2html_wrap_inline5546 . It then enters the region of missing backscatter from the Kapuskasing radar at tex2html_wrap_inline5548 and leaves it again at tex2html_wrap_inline5550 .

Figure 5.35: Peak-map with overlaid flight path of the DMSP F12 satellite: 26 Jan/95

The flux and energy data in Figure 5.36 also show two regions. From 59185 s to tex2html_wrap_inline5554 there is increased flux of tex2html_wrap_inline5340 electrons. Then, from 59235 s there is an increased flux of tex2html_wrap_inline5560 electrons until tex2html_wrap_inline5562 , then of tex2html_wrap_inline5564 electrons until tex2html_wrap_inline5566 , followed by electron energies of tex2html_wrap_inline5418 or more - all relatively high electron energies.

Figure 5.36: Average electron energy and flux determined from SSJ/4 instrument measurements: 26 Jan/95

The ionization rates shown in Figure 5.37 compare well with the radar observations in the fact that there exists a region of high F-layer ionization which is centered around tex2html_wrap_inline5546 , the time when double-peaked spectra were observed.

Figure 5.37: Estimated ionization rates at E- and F-layer heights determined from electron spectra measurements: 26 Jan/95

Figure 5.38 shows the E-layer conductivities, which are small, reflecting the low flux in the precipitation pattern. A sharp gradient in the conductances is observed at tex2html_wrap_inline5572 .

Figure 5.38: Estimated E-layer conductivities from the Robinson model: 26 Jan/95

As in the event on 16 Feb/95, Figure 5.39 shows a velocity map that is dominated by flow in opposite directions. The region of the convection reversal corresponds reasonably well to the location of the double peaked spectra.

Figure 5.39: SuperDARN velocity map: 26 Jan/95

next up previous
Next: 28 Jan/952:13 - Up: Morphology during a Complete Previous: 16 Jan/9516:45 -

Andreas Schiffler
Wed Oct 9 10:05:17 CST 1996