Fig. 5

THEMIS ASI observations and FESO proton auroral observations. Top panel of a shows the THEMIS ASI keogram constructed along the FESO scan meridian. The arc band is shown in orange dotted lines. The lower panel of Fig. 2a shows the ASI counts sampled and averaged over the arc band along the FESO meridian. In Fig. 2b, the top panel shows the FESO 486.1 nm proton auroral intensities versus time and latitude, with the arc band overploted. The 2nd and bottom panel of b show the proton auroral intensities averaged over the arc band, and the total proton auroral intensities integrated over full FESO latitudes, respectively. The scan time (30 s) of each FESO data point is marked by a horizontal bar. Two vertical dotted line throughout the plot denote T0 and T1, the TSSO interval