Proton Auroral Emissions without Electron Auroral Emissions in Long-lasting Complex Substorms

The SI-12 and WIC FUV instruments aboard the IMAGE satellite provide a unique ability to compare LBH and proton auroral emissions. The auroral power allows for the examination of the relationship of proton and electron emissions. In the past, measurements in the LBH band have been used to identify substorms. There are, however, cases where there is significant proton auroral emission while there is little to no electron emission in the LBH band. During intense, long-lasting complex substorms it is possible that while the WIC images show a decreasing intensity and entry into a more recovered state. At the same time, images from the SI-12 camera show increased intensities and possibly further substorms seen only in the proton emissions. An example of this can be seen in the events of November 15, 2001 from 1700-2200 UT. An investigation of this event will be presented and possible explanations of these events will be put forth.