First medium energy neutral atom (MENA) images of Earth’s magnetosphere during substorm and storm-time
نویسندگان
چکیده
Initial ENA images obtained with the MENA imager on the IMAGE observatory show that ENAs emanating from Earth’s magnetosphere at least crudely track both Dst and Kp. Images obtained during the storm of August 12, 2000, clearly show strong ring current asymmetry during storm main phase and early recovery phase, and a high degree of symmetry during the late recovery phase. Thus, these images establish the existence of both partial and complete ring currents during the same storm. Further, they suggest that ring current loss through the day side magnetopause dominates other loss processes during storm main phase and early recovery phase.
منابع مشابه
Calculation of IMAGE/MENA geometric factors and conversion of images to units of integral and differential flux
The Medium Energy Neutral Atom sMENAd instrument flown on the NASA IMAGE spacecraft is a time-of-flight neutral particle imager designed to image energetic neutral atom emissions from the Earth’s inner magnetosphere over an energy per mass range of 1–60 keV/amu. Images are generated by combining data from three separate heads and have a nominal angular resolution of 4° 34°. Here, we present a f...
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