Double dayside detached auroras: TIMED/GUVI observations

On August 19, 2003, TIMED/GUVI detected, for the first time, two separated (double) dayside detached auroras (D-DDA) simultaneously in all the GUVI channels, 121.6 nm, 135.6 nm, LBHS, and LBHL. The D-DDA was located at magnetic latitudes around -57\textdegree and -63\textdegree (L shell 3.4 and 4.9) in the 0900\textendash1030 MLT region. The high-latitude part of the D-DDA is much brighter than the low-latitude part. DMSP particle observation indicates that the source of the D-DDA is energetic (\~10 keV) precipitating protons/electrons from the ring current due to the solar wind dynamic pressure enhancements [Zhang et al., 2002] and/or northward turning of the IMF Bz. Observations of the D-DDA provide the first single-event evidence of multiple peaks in the statistical distribution of proton fluxes at energetic around and below 10 keV at low L-shells [Milillo et al., 2001].